DE102021004029A1 - Wave Rider - Ship's hull with air lubrication and extended or extendable skirts - Google Patents

Abstract

Ships with conventionally shaped hulls consume enormous amounts of propulsion energy to travel on the water surface as they push the water to the left and right. The newly shaped hull uses skirts to only displace water downward, under the ship, and now even uses extendable skirts to increase displacement even further. These extendable skirts (1) are only available along the forward sloping ramp (2) necessary to lead the water far below the ship. On the ascending ramp (3) under the stern, the water then strives for the surface again, whereby the majority of its inherent energy is withdrawn by recuperation and converted into propulsion - whereby a ship with such a wave rider hull can save enormous amounts of propulsion energy Hull is suitable for all ocean liners that have to comply with draft limits in shallow harbor waters (e.g. Port of Hamburg, 13m), but who want to achieve high recuperation performance in the open ocean with the skirts extended.

Description

• 90 Prozent des Welthandels erfolgen aktuell (2019/20) auf dem Seeweg. Die Groesse der Schiffe nahm dabei in den letzten Jahren stetig zu - mittlerweile werden Containerriesen mit einer Kapazitaet von fast 24.000 Containern in Serie gebaut. Die Ruempfe dieser 400 Meter langen Schiffe weisen eine enorme Wasserverdraengung auf und erzeugen deshalb bei ihrer Fahrt durchs Wasser erheblichen Widerstand.

The invention relates to a wave rider ship's hull of the type described in German utility model number 202013 004 518.3. This utility model was registered on May 15, 2013, ie this special hull shape has been known since this date.

• 90 percent of world trade is currently (2019/20) carried out by sea. The size of the ships has increased steadily in recent years - meanwhile, container giants with a capacity of almost 24,000 containers are being built in series. The hulls of these 400 meter long ships have an enormous water displacement and therefore generate considerable resistance as they travel through the water.

There is therefore a high degree of interest in measures to reduce hull resistance in order to be able to reduce the fuel consumption of world shipping in general and of such ships in particular and - as a result - also to minimize the emissions caused by these ships.

When a ship's hull moves forward in water, several resistances appear that inhibit this forward movement. To be named would be (according to their percentage share of the total resistance) the frictional resistance (45%), the shape - and the wave resistance (total 40%), the air resistance (10%) and the turbulence resistance 5%. This information applies to the 'fast journey', e.g. The most important of the resistances is therefore generally the frictional resistance,

There are various approaches to minimize the frictional resistance of the water on the ship's hull. The most promising attempt in this regard is based on the introduction of air as an insulating layer between the water and the ship's hull in the form of so-called 'air film lubrication'. In concrete terms, this means that by blowing out air bubbles under the flat bottom of the ship's hull, the contact of the water with the hull is prevented - which, according to a designer from the Kiel shipbuilding company 'New Logistics' named Udo Wulf, should be able to avoid up to 80% of the friction losses .

But not only for the reduction of the frictional resistance (of a ship's hull in the water) there are promising prospects for a drastic reduction. Also with regard to the shape and wave resistance - which is also enormously important with a share of 40% of the total resistance - strategies for its reduction and even extensive avoidance have already been published. In 2013, for example, a protective right for a specially shaped hull called a wave rider hull was registered with the German Patent Office, which has outstandingly low resistance in terms of its form resistance balance thanks to its unrivaled flat bow line and energy recuperation. In addition, with such a ship's hull, the wave resistance is also drastically reduced, since it takes advantage of the surprising submarine paradox. It is generally known that a submarine reaches a significantly higher speed when traveling underwater (almost 50 percent faster) than when traveling over water. What is peculiar is that its wetted surface (and thus the frictional resistance) is much higher under water than above water! The reason for this astonishing circumstance is that the submarine generates a large wave resistance when traveling over water - optically clearly comprehensible by means of the bow wave (displacement wave), which it pushes ahead of itself - which is completely absent when traveling underwater. One could also say: Since water to be displaced (like electric current) follows the path of least resistance - and the least resistance / i.e. pressure! near the water surface in the layer of air above the water, it logically escapes into this space and piles up there - against gravity - to form mountains, the so-called 'bow wave' (or displacement cell). This bow wave can be equated with lost propulsion energy. As soon as the submarine then submerges and a high column of water stands above the water that has been displaced at depth, it is no longer possible for this part of the water to move to a place of low pressure - the loss from the wave resistance therefore tends towards 0 - which is the case with the U -Boat then manifested in the form of the higher speed under water.

The already mentioned, specially shaped hull called 'wave rider ship hull' adopts this submarine wave resistance avoidance principle and displaces water instead of in the manner of conventional hulls, which are known to displace it close to the surface to the sides, especially in the depths. He achieves this by channeling the water to be displaced with the help of side skirts along a sloping ramp from the bow down to the lowest point of the ship - the amidships positioned threshold - which then only allows this displaced water to spread left and right there where a high column of water already stands over it. The high water pressure there therefore prevents the formation of the usual, distinctive displacement wave, which otherwise inevitably occurs where the hull reaches its largest cross-section (in ships with conventionally shaped hulls near the bow, in the case of a wave rider hull midships). In the case of a surfer ship hull, a displacement wave is therefore only formed to a very limited extent as a result of its depth displacement.

It is now the case that large ships such as container giants that want to call at the port of Hamburg have a draft limit of 13 meters (because this is the only way they can pass through the Lower Elbe, which is still flat - despite the deepening - up to the port of Hamburg). If the hull of such a container giant is designed in the form of a wave riding ship hull, these 13 meters form the maximum possible draft limit - and at the same time also the water displacement depth that can no longer be undercut, since the aprons and sills may only reach down to this level. However, the potential of a wave rider hull, e.g. in terms of its ability to reduce wave drag, could still be significantly improved if it could displace water even deeper than these 13 meters. If it could, for example, push water down to a depth of 20 or even 30 meters, it would be possible to completely prevent the formation of a displacement wave, since the high water column already present under these conditions is already similar to the conditions under which submerged submarines operate. It could thereby reduce its wave resistance to almost 0 - a downright revolutionary prospect for a surface vehicle.

The task must therefore be to modify a wave rider ship's hull in such a way that it can push water even deeper under the ship than before, where the draft of the sill was also the depth limit for the flanking skirts and thus its water displacement capacity - and with this Ability to also improve ship sizes whose threshold when loaded already comes to the maximum (Hamburg-compatible) draft value of 13 meters - and for this new type of hull to also provide an air film lubrication system to reduce friction.

This problem is solved by a novel wave rider ship hull according to the inventive claims of 1 - 10.

The aprons of a conventional wave rider ship's hull in the area of the front half of the ship - ie only along its sloping ramp - are now massively extended.

Since the intention is to channel the water displaced during forward travel as deep as never before under the ship, it must be prevented that it can already spread to the left and right at threshold level. As a result, the left- and right-hand apron boundary may only end where there is already a very high column of water above this water. This is why these aprons have recently been shaped in such a way that, like sheet piling walls, they always have the same overall depth/length and form a channel that extends from the ship's bow down to the threshold. So the lower edges of the skirts now run parallel to the flat bottom of the hull above them. In the case of ships that already have a draft of 13 meters in the area of the sill when loaded based on this new type of wave rider hull design (which would then fail with such, additionally lengthened skirts at the depth limit of the approach, e.g. to the Port of Hamburg), these skirts then have to - and be designed to be extendable.

If a new wave rider ship's hull has a cross-section like that of a typical container giant (underwater hull dimensions of 60 meters wide with a maximum (threshold) draft value of 13 meters, its skirt lower edges then logically have to be there, at the threshold, at a depth of 26 meters (i.e. 13 additional 'sheet piling depth meters'), they want to channel all the water that such a hull cross-section (of 13 x 60 meters) displaces when moving forward, down to the lowest point of the hull bottom, i.e. the area of the threshold In order to guarantee this extensive canalization 'right from the start', such a 13 meter sheet pile wall depth/skirt depth canalization must of course also be maintained throughout, i.e. 'from the ship's bow to the sill' unnecessary. What's more: They can even be completely eliminated there! D When the straight, purposeful upward flow of the water, which was previously displaced by the ship in the area of the front, descending ramp and thus accelerated, takes place due to the laws of nature, as recognized by the Swiss physicist and discoverer Daniel Bernoulli in 1783 - and then in his famous Bernoulli-esque Law formulated - also completely without any further guiding measures! Due to the lower pressure in fast-flowing media - (such as the displacement water - accelerated under the ship by means of the front ramp) there is now for this 'fast' water 'from threshold' - due to its low, it now inherent pressure - there is no longer any possibility of escaping to the outside - because outside of the ship the water pressure is generally higher everywhere because the ambient water there is in a stationary state. It must therefore rise compulsorily and 'invisibly constricted' under the stern and there then transfer the entire power inherent in it to the hull bottom/rising ramp there - to be precise, transfer it back, i.e. return it to the ship - which is typically the basis of the recuperation ability of a wave rider ship hull.

A container giant with a surfer ship hull, whose front half of the ship is now equipped with such extendable aprons, then lowers them in the open water - thus only when it has left the flat coastal waters behind and in scheduled traffic on the oceans of this world with 20 node or more is on the way. Thanks to the effect of these skirts, he can then almost completely avoid his wave resistance - and also greatly reduce his shape resistance (thanks to the recuperation effect generated by the skirts). As soon as this container giant with its novel wave rider hull with extended and - retractable aprons approaches flat coasts - and harbor waters, it retracts these aprons again - and thereby reduces its draft from more than 20 or even almost 30 meters before only 13 meters. Adapted to the low waters in this way, such a ship can then easily navigate the Lower Elbe up to the port of Hamburg, for example. (Although so-called deep-water ports such as the Jade-Weser-Port in Wilhelmshaven only offer fairways up to a maximum depth of 16.5 meters - which makes retractable aprons mandatory for container giants with surfer hulls).

From a surface wetting point of view, i.e. with regard to the frictional resistance of the new inventive wave rider hull with extended or extendable skirts, almost nothing changes compared to a conventional wave rider hull (i.e. without extended/extendable skirts). The increase in the wetted surface, which now results from the extended aprons in the area of the forebody/the sloping ramp on the new product, is offset by a reduction of almost the same extent on the aft body - due to the recently resulting possibility of completely eliminating the previously there (with the conventional wave rider hull concept) existing aprons. And since for the first time air film lubrication in the area of its flat underbody is provided for the novel surfer ship hull according to claims 1 to 10, there should actually be serious potential for reducing friction resistance compared to the balance of friction of a conventionally designed surfer ship hull.

Special advantage: large hull floor area enables significant reduction in frictional resistance thanks to air film lubrication. In the new wave rider hull according to claims 1 to 10, the area of the hull floor that is suitable for reducing frictional resistance by means of air lubrication is much larger than in any other conventionally shaped hull.

Because typical of a conventionally shaped hull are strong constrictions in the bow and stern areas in particular, in order to meet the hydrodynamic requirements - which is why, for example, of the 400 meter hull length of a giant container with a conventional hull, only an area of around 250 to 280 meters is suitable for air film lubrication purposes - because only there is a pronounced flat bottom area.

The situation is different in the case of the waveguide hull according to the invention. It has the ideal hull shape, so to speak, to exploit the potential of air film lubrication to the maximum. Because with him, the flat bottom of the hull stretches in full width from the front at the bow to the back at the stern - and is therefore completely suitable for air film lubrication. And not only that: since the bottom of the hull in the front half of the ship is flanked by aprons on the left and right, this air lubrication also works perfectly there 'right into the corners', since the air cannot escape laterally - unlike with a conventional hull this outflow of air is unavoidable (which has a direct impact on the function).

In terms of water friction resistance reduction on the hull bottom, the new wave rider hull is more effective than any conventionally shaped hull - this air film lubrication can also be used over a flat bottom area that is at least 30% larger than with any conventional hull.

The fact that the hull bottom of a wave-riding ship hull according to the invention is not completely horizontal - like for example the hull bottom of a conventionally designed ship - is irrelevant. Because there the gradient of a new type of surfer hull, e.g. in the area of its front, sloping ramp, is only around 5% (although this value depends in principle on the size of the ship, i.e. it can vary), this angle of inclination is ultimately far too small to have a negative impact on the air film lubrication capacity could. Since air bubbles can only move very slowly in the direction of the rising side with such a flat slope angle, they have no chance of an arbitrary 'movement against the current', for example in the regular service conditions of a container giant (20 knots and more at driving speed). They are propelled down below the forecastle - as they float on top of the down-ramp water current - thereby inevitably acting as an insulating layer between the surfer ship's hull bottom and the water flowing under the hull.

Of course, it is clear that the extended/extendable side skirts of the inventive wave rider hull cause a large wetted surface in the water due to their design - which inevitably results in increased frictional resistance. But first of all, this additional source of frictional resistance of the aprons / i.e. the increased area of vertical walls is opposed - as just mentioned - to the significant reduction in frictional resistance due to air film lubrication on the horizontal ship's bottom. And secondly, it is explicitly thanks to the existence of these skirts that the wave and form resistance of the new ship's hull, which, as already mentioned, accounts for at least 40% of the total resistance when driving fast, is ultimately reduced in the most massive way. And in the end what counts is the bottom line. And in the balance of the overall resistance, the novel wave rider hull according to claims 1 to 10 is superior to any conventional hull design - vastly superior!

Special advantage: wave resistance can be almost completely eliminated due to the extended aprons

The wave drag of a ship is the proportion of the total drag that results (as a loss) as a result of the displacement of water above the level of the sea/water surface.

Even on the basis of the long-known basic model of a wave rider ship hull, in which the side skirts only reach down to the level of the sill in the water (because of the Hamburg limit to a maximum of 13 meters), a significant reduction in wave resistance was possible, since it complete water displaced by it could lead down to a depth of at least 13 meters (rather even a little more). Since the water pressure is known to increase by one bar for every 10 meters of water depth, it therefore displaced it by at least 2.3 bar (this pressure basis results from 1 bar air pressure and 1.3 bar water pressure). For comparison: A conventionally shaped hull, if it has a draft of 13 meters, then logically displaces its water at an average of 6.5 meters, i.e. at only 1.65 bar (1 bar air pressure and 0.65 bar water pressure). In the case of a new type of surfer ship hull with extended or extendable aprons, these protrude - e.g. in the case of a giant container - then slightly down to a depth of 26 - if not even 30 meters. It then displaces its water at an enormous 4 bar! (1 bar air pressure and 3 bar water pressure). Under these conditions, the formation of a displacement wave can then - as already mentioned - be almost completely avoided. A lifting of water above the level of the water surface does not take place. I.e.: Even a gigantic container giant - equipped with such a hull - even if it is traveling at a high speed of over 20 knots - no longer causes any significant water movement as a result of the displacement work it has done.

In the past, for example, when flying across the sea one could easily spot the large ships moving there from many kilometers away by means of the bow wave that emanated from them and spread out behind them over a large area, in the future the opposite will probably be observed . One will be able to detect gigantic ships, which are equipped with a surfer ship hull according to the invention with extendable skirts, by means of the trail of completely still water which they leave behind in the sea. At the forecastle, the sea moving in waves will then disappear between the skirts of such a hull - and emerge again at the rear as a smooth band - as a still surface of water. It is particularly advantageous that, as a direct consequence of the reduction in wave resistance, a reduction in the engine power of the ship is also possible as a result of the invention. Which in turn results in lower fuel consumption. As a result, the size of the fuel tank can be reduced, which in turn increases the payload - the impact of the invention with regard to its potential for reducing the wave resistance of ships thus entails a chain of positive effects.

Special advantage: Form drag losses are largely equalized by recuperation

The form drag is, so to speak, the classic drag component that results as a result of the cross-section of a body when it moves forward in a medium. The shape of the body has a significant influence on its share in the total resistance (e.g. of a ship). A lean, streamlined body has less form drag than a bulging, thick, or angular body. If a ship has a flat bow line (i.e. the hull cross-section increases only slowly starting from the bow), the water that is to be displaced is set in motion much more gradually as a result than with a massive, thick and trough-shaped hull. Advantageously, the foreline of a wave rider hull is flatter from the outset than that of any other hull design, since the wave rider hull does not reach its largest hull cross-section soon after the bow, as is usual with all other hulls, but only in the middle of the ship (actually not until then). slightly after half the length of the ship). And in addition to these favorable initial conditions - from the point of view of form resistance - it also has the outstanding property of being able to regain a large proportion of the form resistance loss that occurs at the front of the ship - when water is displaced downwards. To get it back by means of recuperation - i.e. a return transmission of drive energy to the ship - by means of thrust generation from the water rising again on the rear ramp and pushing back to the water surface from the depths.

Since the surfing ship hull according to the invention with extendable aprons can now advantageously lead the water even deeper down than a conventional surfing ship hull was already able to do so previously, its recuperation capacity is now even improved significantly. The reasons for this immense advantage lie in several factors. Firstly, hydrodynamics plays a role, secondly hydrostatics and thirdly the properties of the water, which Bernouill's law describes.

First: hydrodynamics (science of flowing liquids). If one considers the forward movement of a surfer ship hull according to the invention from a hydrodynamic point of view, the water displaced downwards by the volume of the hull has to travel a longer distance than the surrounding water remaining stationary. Or in other words. The water that is laterally separated from the rest of the water (e.g. the sea) at the front by the aprons and then pushed down by the ramp must definitely reunite behind the ship with this remaining water that was left outside - down to the molecule! Therefore, the part of the water that is pushed under the ship during this process is not spared from moving very quickly up and down again - to then precisely behind the ship this precise reunion with the water left and right of the hull remained stationary to be able to afford. The enormous force that is inherent in the downwardly displaced water during its subsequent upward movement is then derived from this law - and as a result then also the enormous recuperation potential that can be derived on the basis of this water pushing up under the stern. If one abstracts this upward-moving water as a force vector (mass of the water multiplied by its upward acceleration), this can then be divided into two partial vectors. One vertical and one horizontal. The much shorter, vertical vector describes the proportion of force that acts directly upwards on the ship's hull. This share is lost. However, the substantially longer of the two vectors is the horizontal vector. It indicates the thrust potential of this water. Since the water has recently been guided deeper under the ship's hull, its path to be covered is now even longer - as already explained above - which automatically means an increase in the flow speed of this water - and therefore additional acceleration. This in turn results in a lengthening of the horizontal force vector arrow / corresponds to an increase in the thrust potential / which is equivalent to a higher recuperation capacity. Ergo, it helps to save more potential for engine power, so it is more advantageous for the ship / the owner.

Second: The hydrostatics / the water pressure

The physical property of the 'medium water' itself is also decisive for the high recuperation potential of the surfing ship hull according to the invention. The liquid water is characterized in particular by the fact that it cannot be compressed - in contrast to gases, for example. Therefore, the water that is displaced downwards (eg in the sea) also interacts with water layers that are much deeper below it by exerting pressure. The pressure that the displaced water exerts downwards is 'stored' by these deep layers almost without loss, but is actually passed on without delay. Man could also say that this deep stratification of the sea acts in the manner of a large resonance body. The pressurization of this resonance body as a result of the forward movement of the hull - and the water displaced downwards by it via the descending ramp (actio), is followed without delay by the counteracting effect of a pressure retransmission to the water rising again after the threshold on the rear ramp (reactio). This rising water can only spread out where the ship's hull 'makes room' as a result of its forward movement. Because behind the ship the still surrounding water 'stands' like a wall – incompressible, immovable. As the rising water pushes into the gap that opens up as a result of the forward movement of the hull and fills it up continuously, it simultaneously propels the ship in front of it. One could therefore compare this rising water with a standing, undersea wave, which therefore lives up to the name wave rider ship's hull. And this standing wave can reach enormous dimensions in a giant container, for example. Since the skirts extended downwards on such a giant freighter can easily reach down to a depth of 30 meters, this standing submarine wave reaches the format and thrust potential of a Kaventsmann, not to say almost that of a tsunami. And this application of force can then be saved in the drive. These positive hydrostatic properties of water are thus the number two factor which advantageously influences the recuperation potential of a surfer ship hull according to the invention.

• Wie bereits erwaehnt, weisen laut dem bernoulli-schen Gesetz bewegte Fluessigkeiten einen geringeren Druck auf als unbewegte. Die Vorteile die sich daraus fuer die Erfindung ergeben - insbesondere der dadurch moeglich werdende komplette Verzicht auf die Schuerzen im Bereich des Hinterschiffs der Erfindung, wurde ja bereits thematisiert. Der geringe Druck in einer schnellfliessenden Fluessigkeit ist aber auch fuer das Rekuperationspotential des erfindungsgemaessen Wellenreiterschiffsrumpfes bedeutend. Ein erfindungsgemaesser Wellenreiter-Schiffsrumpf mit verlaengerten oder verlaengerbaren Schuerzen hat ja neuerdings das Potential, das gesamte Wasser, das infolge seines Unterwasserrumpfquerschnitts verdraengt wird, unters Schiff zu kanalisieren. Liegt bei einem Containerriesen mit neuartigem Wellenreiter-Schiffsrumpf die Schwelle im beladenen Zustand auf 13 Meter Tiefe, verfuegen auch die Schuerzensegmente vom Bug ab ueber eine Laenge von 13 Metern - und ragen somit an der Schwelle auf bis zu 26 Meter Tiefe hinab. Tatsaechlich wird aber nicht nur dieses - direkt von den Schuerzen flankierte - Wasser verdraengt (in die Tiege beschleunigt). Denn nicht nur der Rumpf verdraengt bei Vorwaertsfahrt Wasser, sondern auch das zwischen den Schuerzen eingefangene, dabei druckbeaufschagte Wasser selbst sorgt (da nicht komprimierbar) auch ausserhalb des Schuerzenflankierten Volumens fuer zusaetzliche Wasserverdraengung Soll heissen: selbst noch vor und unterhalb der Schuerzen - also auch in Bereichen ohne jede mechanische Kanalisierung, wird zusaetzlich Wasser verdraengt, in Bewegung versetzt, beschleunigt. Und Aufgrund des Berneoulli-Effekts kann auch dieses Wasser, das unterhalb des Schuerzen-(kanalisierten) Verdraengungswassers in Bewegung geraet, nicht vollumfaenglich seitlich ausbrechen! Es ist bewegt, beinhaltet daher weniger Druck als das Umgebungswasser, und bleibt (ergo) unterm Rumpf gefangen. Auch dieses zusaetzliche ‚Mehr‘ an Wasservolumen unterm Schiff wird deshalb nach hinten ‚durchgereicht/ angeliefert‘- und erbringt dann beim Aufstieg unterm Hinterschiff einen Zusatzbeitrag zur Rekuperation der urspruenglich am Vorschiff investierten Wasserverdraengungsenergie. Daraus ergibt sich somit dann also erneut, nun zum dritten mal, der Vorteil einer erhoehten Rekuperationswirkung.

Third: Bernoulli's law / the lower pressure in a flowing liquid:

• As already mentioned, according to Bernoulli's law, moving liquids have a lower pressure than non-moving liquids. The advantages that result from this for the invention - in particular the fact that this makes it possible to completely dispense with the aprons in the area of the rear section of the invention - has already been discussed. However, the low pressure in a fast-flowing liquid is also important for the recuperation potential of the surfing ship hull according to the invention. A surfer ship's hull according to the invention with lengthened or extendable aprons has recently the potential to channel all the water that is displaced as a result of its underwater hull cross-section under the ship. If the sill of a container giant with a new type of wave rider hull is 13 meters deep when loaded, the apron segments also have a length of 13 meters from the bow - and thus protrude down to a depth of up to 26 meters at the sill. In fact, however, not only this water - directly flanked by the aprons - is displaced (accelerated into the trough). Because not only does the hull displace water when moving forward, but also the water that is trapped between the skirts and pressurized in the process (since it is not compressible) also ensures additional water displacement outside of the volume flanked by the skirt. That means: even in front of and below the skirts - i.e. also in In areas without any mechanical channeling, water is additionally displaced, set in motion, accelerated. And because of the Berneoulli effect, this water, which starts to move below the apron (canalized) displacement water, cannot fully break out laterally! It is agitated, so it contains less pressure than the surrounding water, and (ergo) remains trapped under the hull. This additional 'more' of water volume under the ship is therefore 'passed through/delivered' to the rear - and then, when ascending under the stern, makes an additional contribution to the recuperation of the water displacement energy originally invested in the forecastle. This results in the advantage of an increased recuperation effect again, now for the third time.

Special advantage: propeller under the forecastle reduces the turbulence resistance at the stern of the ship

When moving forward, a wave rider ship's hull displaces water under the ship using the sloping ramp under its forecastle. This water experiences an acceleration downwards under the forecastle towards the threshold. Since the propeller at the stern of a ship does nothing other than to accelerate the water against the direction of travel, it is obviously advantageous to combine these two processes and to move the propeller to the front and place it there under the forecastle. And ideally as an end piece of the inlet cone positioned there, which ensures the balancing of the wave rider ship's hull, i.e. the stable position of the ship in the water. While it generates the necessary propulsion for the forward movement of the ship, the accelerated water escaping from the screw can also support the water displacement process taking place there in the depths on the descending ramp. And there is a second advantage from this new drive constellation. By eliminating the ship's propeller at the stern, the water displaced by the ship is transferred there to the surrounding water in an extremely homogeneous manner, i.e. with very little turbulence. A circumstance which then contributes to reducing the turbulence resistance of the invention.

• - den Reibungswiderstand (mithilfe einer Luftfilmschmierung) zu minimieren
• - den Wellenwiderstand fast komplett zu eliminieren
• - Formwiderstandsverluste weitestgehend zu rekuperieren und
• - den Verwirbelungswiderstand zu reduzieren

Consequently, with regard to the overall resistance situation of a surfer ship hull according to claims 1 to 10, the following picture emerges. Through him it becomes possible:

• - to minimize the frictional resistance (with the help of an air film lubrication).
• - to almost completely eliminate the wave resistance
• - To recuperate form drag losses as far as possible and
• - to reduce the turbulence resistance

Since the displacement of water under the ship - instead of to the sides - generates such a significant advantage, extended or extendable skirts on surfer ship hulls should soon be just as common an addition as winglets on an airplane wing are today (these also cause a increased resistance - since their positive effect on flow control is so convincing, they can be found on almost every modern aircraft today)

Special advantage: extendable aprons work on the basis of a completely simple mechanism

If very large ships such as container giants are equipped with a wave-riding hull, they already reach the maximum permissible draft of 13 meters when loaded in the threshold area as standard, with which they are just barely suitable for the Port of Hamburg. In order to secure such a ship the recuperation advantages that can be achieved with extended skirts, these must then - as already mentioned - be designed to be retractable and extendable, whereby they can then be lowered in the open ocean, for example, to a depth of up to 30 meters. In view of the fact that such container giants reach hull lengths of up to 400 meters and the skirt-lined, sloping ramp under the forecastle can easily have a length of 200 meters, it is easy to understand that a lowerable skirt as a single - then 200 meters long component per side - would be technically difficult to handle (since aprons of such large dimensions would be very difficult to implement mechanically stable). It is therefore more advantageous to design the lowerable aprons in the form of individual apron segments. This can then be, for example, 10 separate segments of 20 meters each. Advantageously, apron segments of this type are significantly more flexible and easier to handle, since they are not only smaller, but can generally also be retracted and extended independently of one another. In order to ensure the stability of such segments even in heavy seas and also to prevent tilting when extending (lowering) and retrieving (retracting), they are advantageously movably mounted on the basis of a multiple roller guide, which has large distances between the individual roller blocks. Advantageously, the roller blocks run on rails that are fixed inside the apron part, which is firmly attached to the fuselage. In addition, such segment aprons advantageously each have a cover that is attached flush to the ship's side and, in addition to the protective function for the inner segment aprons, also ensures accessibility in the event of maintenance. Equipped and housed in this way, these mobile apron segments function like a drawer that can be pulled out of its receptacle (corresponding to the apron lowering process) and then returned to its receptacle (corresponding to the apron retracting process into the ship's hull)
In order to ensure that these apron segments, which are still huge, can be moved in and out easily, they are designed as floating bodies, which are equipped with a buoyancy body near their lower edge and which also have a flood tank. If this tank is flooded with water, they sink down, guided by multiple rollers. If the tank is then evacuated, they reappear. The buoyancy device integrated into them inevitably ensures that they float on the water surface and can be forced back into their hull sockets. The flooding of these floating bodies (after the ship has left the harbor and is in deep fairway under it at full speed) is - as you would expect - a simple process - you simply open a flooding flap near the lower edge of the apron, which advantageously like a scoop in Direction of travel opens (also a venting valve on the top of the flood tank), and as a result of the forward movement of the hull, the 'passing water' shoots into them - whereupon these apron segments, now weighted with ballast water, immediately rush down into the depths. Logically, in order to get them to surface again, the ballast water with which they were flooded must be expelled again. Classically, it should then actually (after closing the ventilation valve tils on their upper side) compressed air is blown into them - whereby the water would be expelled, they would become lighter and they would therefore float again - a process typically known from the handling of submarines. However, the aprons are not small submarine tanks but rather gigantic bodies, which are also available in an impressive number of 20 pieces (10 per hull side). Evacuating these volumes of ballast water with compressed air would not only require enormous compressor capacities (and thus consume a lot of energy), but would also take an enormous amount of time. A disproportionate amount of time. Therefore, these apron segments are advantageously equipped with a particularly energy-efficient water evacuation device, which makes evacuation independent of the compressor possible (which is why the option of using a compressor then only needs to be kept available as an emergency solution, i.e. as a backup). The basis of this enormously energy-efficient, compressor-independent evacuation device is again the Bernoulli effect, which has already been described twice in this document - in the course of the hydrodynamic effects of the wave rider ship's hull. It states that the static pressure within a liquid or gas drops the more, the greater the flow rate. And since a container giant in ocean traffic is usually traveling at 20 knots (almost 40 kilometers/h) or even more, there is logically a large pressure difference between the stationary ballast water in the flood tanks (the 'inside water') and the outside of the ship (as a result the forward movement of the ship) 'outside water' flowing past very quickly, i.e. the surrounding water / the sea water. And this pressure difference between the inside water (high pressure) and the outside water (low pressure) can be used to evacuate the flood tank of an apron. If an evacuation flap is opened again at the level of the lower edge of the apron (in the vicinity of the flooding flap that is also already placed there), which is positioned near the rear edge of the apron - in alignment 'with the flow' (it is therefore attached at the front and thus opens 'flow-conform' like the aileron of an airplane wing) then, due to the negative pressure in the - by the Forward movement of the ship (relatively speaking) 'fast-flowing outside water' prevails, the inside water is literally sucked out of the flood tanks - i.e. evacuated at high speed.The consequence of this: As the ballast water level in the flood tank of the skirt decreases, its own buoyancy (due to the integrated buoyancy body) increases prevails, moves the apron moves up again within a very short time, back into its torso mount. Without any driving force, without compressor power - just using the pressure difference to the flowing surrounding water. In this manner, 20 aprons can easily and quickly be brought up at the same time - the sole requirement is that the ship makes rapid forward travel. Once an apron has reached the top of its fuselage mount, all you have to do is close the vent valve (on the top of the flood tank) - which means that the apron then remains 'captured' in its fuselage mount! because water entry from below is impossible because the gas / air of the flood tank cannot escape upwards). In this way, the apron segments can be moved with minimal effort - advantageously without any additional engine power. The only requirement is the fast forward movement of the ship. An alternative use of a compressor to move the aprons is then only required in emergencies (e.g. in the event of a complete failure of the ship's drive)

Special advantage: the shape of the extendable aprons is optimized for minimal resistance

In the case of the surfing ship hull according to claims 1 to 10, the water to be displaced is guided downwards via its front, sloping and apron-flanked ramp. These extended or extendable side skirts follow the curved course of the fuselage floor, ie the lower edges of the skirt resemble parallels that occur at a distance from the fuselage floor running above them. In the case of small ships, which have fixed aprons, maintaining such a parallelism is of course easily realizable. The situation is different with large ships such as container giants, whose threshold when loaded is already 13 meters deep and which therefore have to be equipped with apron segments that can be extended and retracted. Unfortunately, the concept of the beautifully curved lower edges of the apron cannot be adopted for such retractable and extendable apron segments. Because although a curved lower edge can of course also be easily executed with segment skirts in the extended state - this picture changes the moment they are retracted and come to rest in their fuselage recesses, then inevitably transforms into a wild sawtooth landscape - with a correspondingly large resistance generation potential. Because although the hull recesses are of course only open at the bottom, the segment skirts stored in them still offer (due to the floating body with which they are equipped, which entails a construction depth that is not negligible) a lot of attack surface for sea water if they do not have a flush finish due to an 'organic underside course'. A condition that cannot be reconciled with the goal of a drag-reduced, flow-optimized hull (even if this condition - driving with retracted aprons without a flush finish - only affects the shallow water mode, i.e. would account for a maximum of 10% of the total driving time).

One thing is clear: Only if the skirts have a straight, horizontal lower edge can they be used to achieve a flush, streamlined fuselage closure when retracted. However, the simplest and most obvious conclusion cannot be drawn from this finding: namely, that as a result of the required straight lower edges for all apron segments, these segments could then simply all be made uniform. So all of them, from the bow to the sill with identical geometry and the same length - which means that they would then protrude into the water as a kind of huge, rectangular curtain. However, since the result of this variant would inevitably be a huge increase in the wetted fuselage surface, i.e. this solution would also result in enormously high frictional resistance - it is unacceptable.

The use of segment aprons, which offer the required horizontal lower edge, but are used in different lengths, remains a viable option. In this way they can comply with the dictates given to them by the curved course of the ship's floor in such a way that they only approach it segment by segment in their attempt to be parallel, which means that when all are fully extended - due to the straight segment skirt undersides - then that image of a descending staircase. The longest of all aprons then logically protrudes into the water at the deepest point of the ship's bottom, where the sill is located - while all other aprons towards the bow are then successively shorter. In this way, on the one hand, the consistent channeling of the displacement water is fully guaranteed down to a depth of 26 meters - while on the other hand, the apron segment area required for this and thus the increase in wetted surface (i.e. frictional resistance) is kept within limits.

As a result of this arrangement of the segment aprons, which was recognized as being advantageous, i.e. arranging them in the extended state in the form of a sloping staircase, it has recently become necessary to profile the lower part of the front side of each segment, i.e. with a profile nose there similar to that found on an airplane wing. Since each segment now "stands in the water flow" with this lower part of its face when moving forward, the resulting resistance must of course be reduced as much as possible.

And since the segment aprons are now arranged in the manner of a descending staircase, with the first, shortest segment at the bow therefore having a significantly smaller surface than the last, which is the longest, it is worth considering individualizing the running width of these apron segments - in order to be able to adjust the surface area of the existing segments (which is also decisive for their weight) to one another. Because with a similarly large surface and approximately the same weight, a uniform design of all segments with regard to their mechanical load capacity could be realized - and the internal components such as floats and flooding tanks could also be dimensioned the same for all segments.

It is therefore advantageous to carry out the first, shortest apron segment directly at the bow with the longest running distance of all, e.g. to design it with a running width of 30 meters instead of the standard size of 20 meters - and to continuously shorten the running distance of the following apron segments. The segment that protrudes furthest in the extended state, the last in the row that sits directly in the area of the threshold, could then, for example, have a running distance of only 10 meters. Through this measure, its surface (despite its great 'draft') can then approach the area values of the other segments, i.e. noticeably reduce them, which can then also significantly reduce the forces with which, for example, the swell can attack this segment.

Special advantage: rotating slats as a simple sealing device between the extended apron segments:

Since the individual apron segments extend downwards from their individual hull receptacles, guided by multiple rollers on lateral guide rails, it is clear that when they are in the extended state, there will be distances between them, i.e. gaps. These gaps should easily reach values of 10 to 20 cm. The task now is to keep these extendable skirt segments in their extended position along the forward sloping ramp have to take, as is well known, to ensure the water canalization in depth when the ship is moving forward. The pressurized water in the area below the front ramp would of course immediately take every opportunity to partially escape through these gaps (flow outside, into the surrounding water, which has a lower pressure level) - if you let it. Since this would reduce efficiency, it must therefore be prevented.

The solution for the reliable sealing between the extended apron segments is the use of simple rotary lamellae, mounted on the rear end faces of the apron segments. As soon as there is a pressure difference and a flow from the inside to the outside begins, these rotary slats open up - and thus advantageously prevent further water drainage. In the form of a further advantageous embodiment, they are also slanted at the top - to automatically fold in when they are loaded from above. I.e.: if the segment is caught up, i.e. retracted back into the hull recess (e.g. before reaching the next port), the slanted upper side of the rotating slat first reaches the edge of the hull mount - which forces the rotating slat to fold in and again flush to the front side of the to snuggle up an apron. This automatic rotary slat also works the other way around: if the rotary slat sticks out when the apron is in the extended state, while the neighboring apron is coming down from above, its lower edge then reaches the slanted upper side of the rotary slat, whereupon it automatically folds in - i.e. makes room.

Special advantage: ship's hull with extendable aprons can be stacked and docked without any problems

When smaller vessels are fitted with a novel wave rider hull, the extended side skirts flanking the forward sloping ramp can be provided in the form of fixed units. Because even if they are fully loaded, such ships never reach a draft at which their entry into harbor waters or other shallow water zones would be in question. And although such permanently installed, extended aprons naturally have a very simple structure and cause much less mechanical effort than the alternative concept based on aprons that can be retracted and extended, i.e. extended, it can still be assumed that this mechanically more complex solution will ultimately prevail - even for small ships. For it is clear that a ship with skirts protruding from its sides to such an extent as, for example, the central centreboard of a large sailing yacht, is much more difficult to launch, to dock or - if it should ever run aground - can be towed free again as a ship with a flat hull contour throughout - and without any additions protruding downwards. And while a sailing yacht, even larger ones, usually weigh so little that they can be lifted out of the water by crane, that is completely unthinkable with cargo ships. That is why the wave rider hull version with extendable, i.e. retractable, aprons will prevail. They can be built in the traditional way in the shipyards of this world, be launched in the traditional way and also be docked again in the traditional way for maintenance purposes. And if the worst comes to the worst, they can easily be dragged out again (since they will always be out and about in shallow water with their aprons pulled up). And every owner is happy to accept the greater mechanical effort that the retractable and extendable aprons will ultimately cause - if at the end of the day (due to lower fuel costs) it makes itself felt in cash.

Special advantage: Despite the installation of the apron in the ship's hull and its covering with cover plates, the usual port towing operation remains

As soon as a ship equipped with a new type of wave rider hull approaches its destination port or shallow waters, it retracts its extendable skirts into the hull recesses. Arrived at the port of destination, it is then often the case that the support of port towing tugs is required in narrow harbor basins in order to be able to dock safely at the quay without any problems. High forces are often exerted on the side of a large cargo ship, because the padded bow of the tug - after it has attached itself to the side of the cargo ship above the waterline - then pushes the same with 1000 horsepower in the desired direction.

Advantageously, this application of force is also possible without any problems on a ship that is equipped with a novel surfing ship hull according to the invention with extendable skirts. Because the ship's walls have large stability reserves - despite the hull mounts positioned there for the aprons, which are covered with cover plates. Because the aprons are always inserted into their hull mounts before the ship enters the port will drive, a hull of the invention is typically always present as a triple sandwich at waterline height. At the front the cover plate (which can be removed for maintenance or repair purposes), then the stable apron as a middle layer and at the back the rear wall of the fuselage mount of this apron. A board wall present in such a form as a composite can therefore withstand any force applied from the outside, no matter how strong. resist

Special advantage: despite the slightly lower loading capacity, transport is much more economical

A typical feature of a wave rider hull is that it has 2 ramps, a front, sloping ramp and, after the threshold, a rear, sloping ramp. Based on this basic configuration, which, if one were to cut open the hull and look at it from the side, is vaguely reminiscent of a bulbous V, it is clear that a hull shaped in this way protrudes deeper into the water in the area of its threshold than a comparable conventional one, i.e. trough-shaped Hull, which in section and in a side view is more similar to a U-shape. For smaller ships that are not subject to maximum draft problems, this aspect is irrelevant. For example, if you have a hull that is designed for 10,000 tons deadweight, then you can load up until this limit is reached - regardless of whether you have a conventional hull shape or a surfer hull shape. feature. The 10,000 ton ship with a wave rider hull shape then protrudes 1 or 2 meters deeper into the water in the area of its threshold - but this is ultimately irrelevant. The situation is completely different when it comes to very large ships, e.g. container giants with a load capacity of around 200,000 tons. Even based on a conventional, trough-shaped hull, they often have a draft of 16 meters when fully loaded. For example, in order to be able to call at the port of Hamburg, which only allows a draft of 13 meters, you have to start with a slightly reduced load from the outset.

The largest container ships today have a capacity of approximately 24,000 standard containers - when they call at Hamburg, such ships then arrive from offshore with about a quarter less payload, i.e. 'only' 18,000 standard containers. If such container giants are now equipped with a surfer ship hull according to the invention with extendable skirts according to claims 1 to 10, they can of course load a little fewer standard containers due to their 'remotely bulbous V-like hull', which is already slightly lower in the water from the outset than their conventional trough-hulled counterparts. On a trip to the port of Hamburg and the depth limit there of 13 meters, they could perhaps only load 15,000 standard containers. However, thanks to the recuperation effect of their fuselage, they would deliver these 15,000 containers after completing the intercontinental voyage distance with unrivaled low fuel consumption. Today's container giants have a fuel consumption of over 350 tons per day, which represents a value of approximately 100,000 dollars - for a daily ration!. If now a substantial part of this sum suddenly disappeared - would it still be decisive that a ship instead of 18,000 containers, for example, can only load 15,000 containers? Certainly not. On the contrary: since in the future container giants with a surfer ship hull according to the invention with extendable skirts will suddenly be able to offer freight rates much cheaper than their brothers equipped with conventional hulls thanks to their greatly reduced fuel consumption, it could be that in intercontinental shipping traffic there will soon only be a single container giant ship type Freight routes of this world dominate: container giants on the basis of an inventive wave rider ship hull with extendable aprons.

• Zeichnung 1 : Die Uebersichtszeichnung eines erfindungsgemaessen Wellenreiterschiffsrumpfes als Seitenansicht und darunter 2 perspektivische Darstellungen der Vorschiffe von unterschiedlich grossen Wellenreiter-Schiffsruempfen im Schnitt . durch deren Schwelle.
• Zeichnung 2 u 3: Die perspektivische Darstellung eines erfindungsgemaessen Wellenreiterschiffsrumpfes mit fest an den Schiffsrumpf angeschlagen, verlaengerten Schuerzen in einer Seitenansicht (Zeichnung 2) Dersellbe Rumpf ist dann auch noch in Vorderansicht ohne Aufbauten in der rechten unteren Ecke dieses Blattes zu sehen (Zeichnung 3).
• Zeichnung 4 : Das grob vereinfachte Diagramm der Druckverteilung unter einem erfindungsgemaessen Wellenreiterschiffsrumpf mit verlaengerbaren Schuerzen, wie es sich unter Einfluss des bernoulli-schen Gesetzes bei Vorwaertsfahrt des Schiffes ergibt
• Zeichnung 5 : Die perspektivische Darstellung eines erfindungsgemaessen Wellenreiterschiffsrumpf mit verlaengerbaren Schuerzen ‚von unten‘, in einem Zustand mit eingefahrenen Schuerzen.
• Zeichnung 6 : Die perspektivische Darstellung eines erfindungsgemaessen Wellenreiterschiffsrumpf mit verlaengerbaren Schuerzen ‚von unten‘, in einem Zustand mit ausgefahrenen Schuerzen.
• Zeichnung 7 : Die perspektivische Darstellung eines erfindungsgemaessen Wellenreiterschiffsrumpf mit verlaengerbaren Schuerzen im Blickwinkel einer Seitenansicht von unten, unter besonderer Bezugnahme der Druckausuebung auf tiefe Wasserschichten weit unterm Schiff
• Zeichnung 8 : Detailansicht eines Schuerzensegmentes in eingefahrenem Zustand, mit geoeffneter Flutungsklappe, als perspektivische Darstellung
• Zeichnung 9 : Detailansicht eines Schuerzensegmentes in ausgefahrenem Zustand mit geoeffneter Evakuierungsklappe, als perspektivische Darstellung
• Zeichnung 10 : Die Seitenansicht eines vollbeladen Containerriesen, der mit einem erfindungsgemaessen Wellenreiterschiffsrumpf ausgruestet ist, dessen verlaengerbare Schuerzen voll ausgefahren sind. In der Rumpfmitte zeigt ein Schnitt die maximale Stapeltiefe der Container an dessen Schwelle

The invention is explained in more detail below using an exemplary embodiment with reference to the drawings 1 to 10. It shows:

• Drawing 1: The overview drawing of a surfer ship hull according to the invention as a side view and including 2 perspective representations of the forecastles of differently sized surfer ship hulls in section. through their threshold.
• Drawing 2 and 3: The perspective view of a surfer ship hull according to the invention with extended aprons firmly attached to the hull in a side view (drawing 2) The same hull can then also be seen in a front view without superstructures in the lower right corner of this sheet (drawing 3) .
• Drawing 4: The roughly simplified diagram of the pressure distribution under a wave rider ship hull according to the invention with extendable aprons, as it results under the influence of Bernoulli's law when the ship is moving forward
• Drawing 5: The perspective view of a surfer ship hull according to the invention with extendable aprons 'from below', in a condition with the aprons retracted.
• Drawing 6: The perspective view of a surfer ship hull according to the invention with extendable skirts 'from below', in a state with the skirts extended.
• Drawing 7: The perspective view of a surfer ship hull according to the invention with extendable skirts in a side view from below, with special reference to the pressure exerted on deep water layers far below the ship
• Drawing 8: Detailed view of an apron segment in the retracted state, with the flooding flap open, as a perspective representation
• Drawing 9: Detailed view of an apron segment in the extended state with the evacuation flap open, as a perspective representation
• Drawing 10: The side view of a fully loaded container giant, which is equipped with a surfer ship hull according to the invention, whose extendable aprons are fully extended. A section in the middle of the fuselage shows the maximum stacking depth of the containers at its threshold

Drawing 1 shows a side view of a surfer ship hull according to the invention (as an overview drawing) and two versions as sections through the hull (whereby only the forecastle is shown) - which are now characterized in that they only have aprons in their front half of the ship, these but now as extended side skirts (1). In the case of the smaller hull on the left side of the drawing, these are firmly attached to the ship's hull in their entirety, while in the case of the right, larger hull, that of a container giant, they are in the form of two separate sections. Only the upper section is firmly attached to the fuselage, whereas the lower section is realized in the form of apron segments (2) that can be retracted and extended. Due to this design, when the new ship is moving forward, it is possible to bring more water under the ship to the sill (4) using the sloping ramp (3). The drawing shows 2 different positions of the retractable and extendable apron segments (2) on the new fuselage of the container giant, on the right side they are in the extended state, while they are retracted on the left side - and there only dashed outlines their extended position, which they would have in the maximum lowered state). The consequence of equipping a new type of wave rider ship's hull with retractable and extendable apron segments (2) is that this ship can easily comply with the depth limit of the Port of Hamburg of 13 meters when these are retracted - i.e. in shallow water mode. The apron segments (2), which can be extended and retracted, run on multiple roller guides (5), which on the one hand ensure that they can be moved without tilting and which also guarantee that they are mounted so stably that they can also withstand heavy seas . The apron segments (2) that can be retracted and extended are also available as hollow structural elements, in each of which a floating body (6) and a flooding tank (7) are integrated, with the respective filling level of the flooding tank (7) forming the basis for whether the one and extendable apron segments (2) float up or sink into the depths. If an inlet flap (8), which is located in the front area of each retractable and extendable apron segment (2), near the lower edge of the apron, is opened, water can penetrate into the flooding tank (7) and the retractable and extendable, which is then weighed down as a result of the water ballast Bring the apron segment (2) to drop. The outlet flap (9) sits at the same height as the inlet flap (8). In other words, it is also positioned near the lower edge of the apron, but sits in the rear area of the apron segment (2), which can be extended and retracted. If this outlet flap (9) is opened while driving (with the inlet flap (8) closed, the flooding tank (7) empties as a result of the Bernoulli effect and the retractable and extendable apron segment (2) floats up again, i.e. moves upwards to An air inlet and outlet valve (10) enables controlled air inflow and outflow during flooding or emptying of the flooding tank (7) and also acts as access for compressor air to this flooding tank in an emergency (7), in order to be able to free it from its ballast water loading without the help of surrounding water flowing past. The ship's propeller of the invention is now located under the forecastle, namely as an end piece of the inlet cone (11). A double rudder system ( 12) is used, whereby each of the two rudders located under the stern follows a continuation d it corresponds to lengthened lateral aprons (1), and functionally they only deflect alternately and only inwards.

• Zeichnung 2 zeigt in seitlicher Ansicht und als perspektivische Darstellung einen erfindungsgemaessen Wellenreiterschiffsrumpf, dessen verlaengerte Schuerzen ausschliesslich im Bereich seiner vorderen, abfallenden Rampe hinab in die Tiefe ragen - und dabei in Gaenze fest an den Schiffsrumpf angeschlagenen sind. Der Rumpfboden (siehe gestrichelte Linie) verlaeuft in der Wellenreiterschiffsrumpftypischen Form eines bauchigen V's - wobei dessen Form dann als Vorlage dient fuer den Verlauf der Unterkanten der verlaengerten seitlichen Schuerzen unterhalb von ihm.. Fuer die unerlaessliche Stabilisierung dieser Rumpfkonfiguration, die im Wasser, ohne weitere Massnahmen volatil waere, sorgt ein zweites Auftriebsvolumen, das des am Bug sitzenden, voluminoesen wulstfoermigen Einlaufkegels. Wie in der Zeichnung erkennbar ist, sind die beiden unterm Hinterschiff verorteten Ruder in der Art positioniert, dass sie in Fortsetzung der Linienfuehrung der verlaengerten seitlichen Schuerzen auftreten, wobei sie funktionsseitig nur wechselseitig und dabei nur jeweils nach innen ausschlagen.

Drawing 2 and 3:

• Drawing 2 shows a side view and a perspective representation of a surfer ship hull according to the invention, the lengthened aprons of which are exclusively in the area of its front, sloping ramp protrude down into the depths - and are firmly attached to the ship's hull in their entirety. The bottom of the hull (see dashed line) runs in the form of a bulbous V, which is typical of a wave rider ship hull - the shape of which then serves as a template for the course of the lower edges of the extended side skirts below it. For the indispensable stabilization of this hull configuration, which in the water, without further measures would be volatile, a second buoyancy volume is provided by the voluminous, toroidal inlet cone located at the bow. As can be seen in the drawing, the two rudders located under the stern are positioned in such a way that they appear as a continuation of the lines of the extended side skirts, whereby they only deflect alternately in terms of function and only in each case.

Drawing 3 shows the same hull in front view without superstructure. The extended aprons clearly exceed the level of the bottom of the fuselage on the left and right. In between sits the voluminous, bead-shaped inlet cone. Above this is the overwater bow area, shaped in the manner of conventional ship hulls.

Drawing 4 shows a greatly simplified, schematic representation of the pressure distribution in the water, as it results in the areas next to and under a surfer ship hull according to the invention with extended aprons, when it moves rapidly through the water. In the areas to the left and right of the hull, the water is unmoved, i.e. static. The speed 'V' is therefore entered with the value 0 everywhere. Only the pressure 'P' changes, it increases linearly with the depth, i.e. evenly, in the representation in 10 gradations, pressure level P 1 to P 10. Under the hull, however, things look different, there dynamic conditions prevail. Directly under the threshold, the displacement water shoots through under the hull at a high speed of V 30. If knots were used as the unit of speed, the speed below the threshold would be much higher than, for example, the ship's speed itself, which is usually only around 20 knots in international liner service conditions. During the course of the forward movement of the ship within the skirts from the bow, this displacement water was accelerated downwards by the front, sloping ramp, so to speak, 'like a block' and therefore - thanks to the identical speed distribution within this block - has an almost homogeneous pressure level P1. P1 - i.e. a very low pressure level (for a depth level where otherwise pressure levels with values of P 3 and P4 actually prevail) - corresponds to the pressure conditions as they prevail on the water surface - and results from the high flow rate of this water, which according to the Bernoulli's law is reflected in a pressure reduction.

Directly below the lower edges of the apron, the water displaced downward can also spread to the left and right, resulting in a rapid decrease in pressure and water speed. Therefore, the individual pressure levels (P2, P3, P4 and P5) are very close together. This decrease in pressure and speed then slows down more and more, the further the process continues downwards, until pressure level P 10 equalizes between the pressure of the surrounding water and the pressure conditions under the ship.

As already mentioned, this representation based on pressure values, which are simply updated downwards along vertical lines, represents a greatly simplified system that does not correspond to reality. In fact, it is to be expected that the lines, which correctly depict the pressure distribution under the ship, are more like a pear shape. However, a meaningful and reliable course of the actual pressure values can only be determined using 'in situ' measurements, i.e. measurements that take place directly on site (directly on the ship / in the sea or on a scaled-down model in the flow channel).

Drawing 5 shows a wave rider ship hull according to the invention with extendable aprons in a view 'from diagonally below', with the retractable and - extendable apron segments, whose occurrence is only limited to the front half of the ship, are completely retracted into the ship's walls and only their local stowage positions in the form of dashed lines is illustrated. It is clearly recognizable that the running distance of the individual apron segments changes, it decreases more and more from bow to stern, a measure that is due to the endeavor to match the surface of the individual apron segments as much as possible in order to standardize the basic mechanical equipment of these segments (equally dimensioned mechanical load tolerance of the multiple roller guides, equally dimensioned floating body size, equally dimensioned flooding tank dimensions, etc.) It is also clearly visible in the drawing that in this 'shallow water mode' of the ship the maximum draft of the hull is on the threshold, which is not the case for other ship components either fallen below - a depth limit with which the ship can comply with the 13 meter draft restriction of the Port of Hamburg and which - as can be seen in the drawing - is not undercut by any other part of the ship.

Drawing 6 shows a surfer ship hull according to the invention 'in motion' with extendable skirts in a view 'from diagonally below' - in deep water mode, i.e. with completely extended skirts. In the manner of a descending staircase, these protrude relatively little at the front and then more and more in the further course, whereby they can reach a depth level of up to 30 meters in the threshold area. Assuming a threshold draft of 13 meters, this means that the skirts protrude an additional 17 meters from the ship below from this level. Here, too, the decrease in the length of the individual apron segments is clearly recognizable, i.e. that the structure begins at the bow (where the segment with the longest length is located) and then finally continues to the area of the threshold (where the segment with the shortest length is then located). forms the conclusion)

Using 'drawing magnifying glasses' (see illustrations in the circles), 2 details are also particularly illustrated. In the smaller circle on the left, the situation of the front edges of the apron segments is illuminated in more detail when they are extended. It is clearly recognizable that the stepped arrangement of the apron segments means that their front edges are exposed to direct seawater flow in the lower area. In order to keep their resistance as low as possible, they are designed like the nose of an airplane wing in this area, i.e. they are provided with a profile.

In the larger circle on the right, the situation of the gaps between the aprons is shown, as it occurs when these are extended and the ship is at full speed. Since the water displacement of the ship in the area of the front, sloping ramp, i.e. in the space between the extended skirts, increases the pressure, this pressurized water would of course use every gap between the skirts to flow outwards, i.e. into the area of lower pressure there of the surrounding water. Since this would result in efficiency losses, but gaps between the aprons can never be completely prevented, it makes sense to take countermeasures. This problem can easily be solved by integrating simple rotary slats into the rear end faces of the apron segments. As soon as there is a difference in water pressure between inside and outside (symbolized by the symbols + and -), these rotary slats open up and thus prevent further water drainage. Since they - in the form of an additional - additional advantageous embodiment - are also beveled at the top, they fold in automatically when they are loaded from above. I.e.: if the segment is caught up, i.e. retracted back into the hull recess (e.g. before reaching the next port), the slanted upper side of the rotating slat first reaches the edge of the hull mount - which forces the rotating slat to lie flush against the rear apron front side again. So it never stands in the way of the downward and upward movements of the apron segments.

Drawing 7 shows a ship equipped with a wave rider hull according to the invention, which is equipped with extendable aprons in the area of its forecastle/the area of the front, sloping ramp, in a perspective view when moving forward, in a mixture of side view and view from below. The extended side skirts in the area of the front, sloping ramp and the area below (thanks to Bernoulli's law) ensure that the water is displaced downwards in particular. (For the sake of clarity, only the starboard side of the ship is shown in the drawing / the rear row of the apron segments is shown in the drawing). The line course of the water flow under the ship makes it clear in this drawing that the pressure exerted by the fore ship / its sloping ramp on the water when sailing forward has an effect even down to the deep water layers. However, the energy that has to be used for this pressurization / water displacement is not lost, but is transferred back from the water when it rises again at the stern to the ascending ramp there / to the ship.

This fact can also be understood using the two vector diagrams that are positioned in the drawing below the course of the flow lines. In the diagram on the left, the force arrow pointing downwards corresponds to the drive energy that has to be invested in total. This can be broken down into a horizontal vector, which is directed against the direction of movement of the ship and corresponds to the resistances that occur (shape resistance, frictional resistance, wave resistance, etc.) and which unavoidably arises in the course of water displacement when the ship is moving forward. In addition, the vector arrow acting vertically downwards reflects the loss that occurs as a result of the pressurization of the deep water layers. However, this amount is - how already mentioned - not lost, since water is generally an enormously flexible element and therefore immediately returns this applied pressure like a resonance body by pushing directly to where the next reachable place of the lowest pressure level is. This is the area of the rising water under the stern, i.e. the rear, rising ramp located there.

The situation there is illustrated by the second diagram, i.e. the diagram on the right. The arrow pointing diagonally upwards clarifies the total energy that resides in this upward-moving water. This force vector can in turn be broken down into two individual vectors. One of them, the short vector arrow, which covers about 30% of the initial force, points vertically upwards, so it presses against gravity from below against the wave rider ship's hull with extendable aprons. This part of the power is lost. The other, the long vector arrow, encompassing about 70% of the force, is pointing horizontally backwards. With this proportion of force, the water that has been set in flow presses against the static, unmoving surrounding water, which stands directly behind the ship like a wall. This in turn means (since water cannot be compressed) that the water literally hits this wall and - since there is no further progress at the back - pushes forward and the ship's hull is driven in front of it in the form of a standing wave. As mentioned, this boost in recuperated energy corresponds to an enormous 70% of the total energy invested! Even if one subtracts the higher frictional resistance on which a new wave rider hull is based (→ higher wetted surface as a result of the additional hull surfaces caused by the skirts - which do not occur in a conventionally designed hull) and whose proportion would be estimated at a full 50% more ( As a reminder: the share of frictional resistance in the total resistance is about 45%), there would only be a worsening of the total resistance balance of about 22.5% - which, however, taking into account the air film lubrication potential on the ship's bottom, is not just compensated, but in all likelihood can even be overcompensated! The increased shape resistance, which a wave rider hull with extendable skirts also causes (as a result of the water that has to be displaced into deeper layers by means of this hull shape / i.e. at higher pressure than with conventional hulls), is insignificant - since this higher effort is largely recuperated by recuperation becomes.

In summary, the following can be stated: Since, taking into account the air film lubrication potential of a new type of surfer ship hull, its frictional resistance should not differ significantly from that of a comparable conventionally designed hull, the massive reduction in wave and form drag can finally be booked on the plus side of the invention. The wave resistance, which is completely eliminated, accounts for approx. 10% of the total resistance, the form resistance, which is reduced by approx. 70% by means of recuperation, is reflected with a share of approx. 20% in the overall drag reduction balance. Adding in an expected reduction in turbulence drag by a few percent would eventually result in a total drag reduction of more than 30%. I.e.: A surfer ship hull according to the invention with extended or extendable aprons should probably consume up to 25% less fuel from the point of view of fuel consumption than a ship hull designed according to conventional design.

Drawing 8 shows a perspective view of a single apron segment in its position on the wave rider hull in the retracted state. In order to give the best view of the important details, the ship's hull is shown in a sectional representation (hatched) at threshold height and the apron segment is graphically freed from any paneling - i.e. neither the cover plate nor the profile nose prevent a clear view of this mechanical component.

The arrangement of the multiple roller guides can be seen at the top of the picture. Their generously designed design, with significant distances between the individual roller blocks, ensures that the movable apron segment can be guided up and down the ship's hull in a stable manner without the risk of tilting, and that it can also withstand the heaviest seas. At the very bottom of the apron segment you can see the inlet flap (rectangle in the foreground) and the outlet flap (rectangle on the right edge of the picture). In addition, the floating body (double hatched). The situation in which this ensemble finds itself is assumed to be that the ship is moving forward, symbolized by the large arrow at the bottom edge of the picture. The inlet flap is open to the front, i.e. in the direction of travel (see small, curved arrow, it is attached to its rear edge), which allows ambient water to penetrate into the flooding tank - symbolized by the two small double arrows. The weighting of the apron segment by this ballast water can no longer be countered by the buoyancy of the floating body - which is why the apron segment then und avoidable rushes into the depths. This process of movement is illustrated by the large arrow pointing downwards in the middle of the picture.

Drawing 9 shows a perspective view of a single apron segment in its position on the wave rider hull in the extended state. Here, too, for better understanding and in the interest of a clear view of the graphic details, the ship's hull in the area of the sill was cut in section (hatched area) and any covering of the apron element such as cover plate or profile nose was omitted.

The arrangement of the multiple roller guides can be seen again at the top edge of the picture - this time in a position in which they have slid down completely to the lower stop of the guide rails. At the very bottom of the apron segment you can see the inlet flap (rectangle in the foreground) and the outlet flap (rectangle on the right edge of the picture) again - in the form of 2 rectangles. In addition, again the floating body (double hatched). Here, too, it is assumed that the ship is moving forward as the situation in which this ensemble finds itself, symbolized by the large arrow at the bottom edge of the picture. The inlet flap is closed. The exhaust hatch is open at its trailing edge (see small arrow pointing away from ship, it is hinged at its leading edge). Due to the ship's forward travel, due to the Bernoulli effect, there is less pressure in the surrounding water flowing past than in the stationary flooding tank water. Therefore, this flooding tank water is sucked out through the opened outlet flap. This process is symbolized by the two small double arrows. This loss of ballast water then ensures that the buoyancy of the floating body gains the upper hand in the apron segment - and it therefore floats upwards. This process of movement is made clearer by the large arrow placed in the center of the picture and pointing upwards.

Drawing 10 shows a fully loaded container giant in the form of a side view, equipped with a surfing ship hull according to the invention. Its extendable aprons, which are limited to the area of the front half of the ship, are fully extended and in their ensemble give the image of a descending staircase.

In the middle of the fuselage, an indentation in the fuselage shows the maximum stacking depth of the containers in the threshold area. Although in the middle of the hull it is almost identical to container giants with a conventional hull shape, the stacking depth is lower to the left and right of it - the total loading capacity is therefore reduced - but this is due to the enormous number of containers that can also be transported by a container giant that is equipped with a surfer ship hull according to the invention , is not of great importance, all the more so as he can then deliver his containers at unrivaled low freight rates as a result of reduced fuel consumption. The container giant with a conventional hull then falls by the wayside despite its higher container transport capacity.

Claims (10)

Wave rider ship's hull, characterized in that it only has side skirts in its front half of the ship, limited to the area of the front sloping ramp (3), these now appearing there as extended side skirts (1), the lower edge of which is continuous from Bow to the threshold (4) runs at a uniform distance from the ship's bottom - and that it is also equipped with an air film lubrication system on the ship's bottom. Wave Rider Hulk behind claim 1 , characterized in that the extended side skirts (1) can on the one hand be designed entirely as units fixed to the ship, but on the other hand they can also occur in a version where they are fixed to the ship only down to the level of the sill (4). Ship are attached and their remaining structural depth manifests itself in the form of apron segments (2) that can be retracted and extended. Wave Rider Hulk behind claim 2 , characterized in that the apron segments (2) that can be retracted and extended each have a straight lower edge aligned parallel to the deck line, so that they can therefore, in their entirety, still approximately follow the primacy of the shape of the ship's bottom and, in the fully extended state, they now have the image of a descending Hand in stairs, the top step of which begins at the bow, at the lower edge of the apron there and ends below the threshold with its lowest step. Wave rider hull according to claims 2 and 3, characterized in that the retractable and extendable apron segments (2) have multiple roller guides (5) with which they are guided along the inside of the extended aprons (1) and that they are a Hohlbaukoerper exist, in each of which a floating body (6) and a flooding tank (7) are integrated as elements, which are desired by appropriate control for each Up and down movement of these retractable and extendable apron segments (2) can ensure. Wave Rider Hulk behind claim 4 , characterized in that the floating body (6) is positioned in the lowest area of the retractable and extendable apron segments (2). Wave rider ship hull according to claims 2 to 5, characterized in that the retractable and extendable apron segments (2) at floating body (6) level have an inlet flap (8) and an outlet flap (9) on their outside, which with a corresponding Control vobestromemendes ambient water in the flooding tank (7) can let in or out. Wave Rider Hulk behind claim 6 , characterized in that the inlet flap (8) is positioned in the front area of each retractable and extendable apron segment (2) and opens forwards against the flow, comparable to an engine hood, while the outlet flap (9) is in the rear area of a of each retractable and extendable apron segment (2), where it is attached to its front edge so that it spreads backwards when opening, comparable to the way an aircraft's aileron lifts off the wing when it deflects upwards. Wave rider hull according to Claims 6 and 7, characterized in that the flooding tank (7) is emptied via the outlet flap (9) as a rule solely by using natural forces, as described by Bernoulli's laws, i.e. due to the negative pressure in a fast-flowing ambient current, and only in emergencies or exceptional cases does a compressor-based expulsion of water from the flooding tank (7) take place. Wave Rider Hulk behind claim 8 , characterized in that there is an air inlet and outlet valve (10) on the top of the flooding tank, which not only allows the controlled air flow out and inflow during the up and down movement of the retractable and extendable apron segments (2), but also acts as access for compressor air to the tank - in order to be able to free the retractable and extendable apron segments (2) from ballast water if necessary without the help of surrounding water flowing past, in order to be able to retract them independently of environmental conditions. Wave rider hull according to Claims 1 to 9, characterized in that its ship's propeller is positioned under the forecastle, specifically as an end piece of the inlet cone (11) located there, and that a double rudder system (12) is provided for ship steering, with each of the two rudders located under the stern corresponds in its line guidance to a continuation of the lengthened lateral skirts (1), and functionally they deflect only alternately and only inwards.

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