DE10338483A1 - Solar collector has vortex device to stir up heat carrier fluid as it flows through absorber to absorb absorption heat for better heat transfer - Google Patents

Abstract

The solar collector has a reflector (1) for reflecting incoming rays and directing the reflected radiation in a focal plane (2). An absorber (3) in the focal plane absorbs the radiation to convert it into absorption heat. A heat carrier fluid (4) which flows through the absorber to absorb the absorption heat is stirred up through a vortex device (5) which has profiling on at least some areas of the inside wall of the absorber.

Description

The The present invention relates to a solar collector, at least a reflector for reflecting incoming radiation and for Collimating the reflected radiation in a focal plane; one in the focal plane or its surroundings formed absorber for Absorbing the collimated in the focal plane radiation and the Converting the energy of the absorbed radiation into heat of absorption; and with an absorber flowing through it Heat transfer fluid for absorbing the heat of absorption.

The Development of new technologies in the field of solar technology getting faster and faster. Here is an important project for use Solar energy is the so-called solar technology, which uses solar energy not like photovoltaics to produce electricity, but of heat is being used. The development of innovative solar collectors plays a role here a big Role. This is a thermally insulated absorber used by a heat transfer fluid flows through becomes. That heat transfer fluid is usually a mixture of water and antifreeze. This liquid then heats the hot water supply. The solar technology becomes the Time mainly for heating private homes, for warming of swimming pools and swimming pools and used for heating halls.

at Solar technology basically distinguishes between two main areas of use - hot water production and the space heating. From the environmental point of view is the hot water most suitable, since the consumption of heated water over the Not much changed during the year. With today's solar systems can be an average of 65% of the annual Hot water consumption obtained by solar energy. For the technical In order to implement the solar technology, a solar collector is needed consists of an absorber, which reduces the incident solar radiation converted into heat. This absorber is thermally insulated and will from a heat transfer fluid flows through. By a solar controller, the temperature at the collector and in the hot water tank is checked. If the Temperature at the collector exceeds a certain threshold, the liquid starts to circulate and heat the store. The absorber is ever according to usage of black metal or plastic strips, with a heat transfer tube are connected, which contains the heat carrier. Of the Absorber gives the excess heat in form of long-wave heat radiation from.

The At present the most important collectors are flat plate collectors and vacuum tube collectors. Of the Flat plate type is usually used for brackish water heating and / or for heating support used. The main components of this collector are an absorber, a thermally insulated housing and a transparent cover. This transparent cover causes that due to the specific transmission properties of the transparent Materials only little heat radiation from the absorber to the external radiation is delivered. In addition takes over The cover provides a protective function to the absorber from the weather protect. The absorber is usually made of black-coated aluminum or copper sheet with high heat absorption and low heat emission and is connected to a piping system through which a frost-proof heat transfer medium pumped becomes. An additional Insulation on the back of the absorber and on the side walls causes heat loss through heat conduction can be reduced. To possible To reduce convection losses in the collector, there is also the Possibility, To pump out the air in the collector from the interior. These collectors are called vacuum flat-plate collectors.

The tube collector - also called a vacuum tube collector - differs from a flat plate collector in that an air-empty area between the cover and the absorber ensures particularly good insulation. For this reason, a tube collector has up to 20% higher efficiency than the standard flat plate collector, where the efficiency is the ratio of useful energy (heat) to energy used (solar radiation). A vacuum tube collector detects an absorber, which is located in an evacuated, pressure-resistant glass tube. The heat transfer medium then flows through the absorber either directly in a U-tube or in countercurrent through a tube-in-tube system. A collector consists of several connected in series or connected via a manifold pipes. Such solar panels are known, for example, from AT-344375 or from AT-352354. Here, absorbers are used in the form of flat tubes, which are arranged in channel-shaped reflectors. In this construction, the direct irradiation of the line sections of the absorber deteriorates at low incidence of light by shading the reflector edges, the farther below these are removed from the cylinder axis of the channel profile. Nevertheless, in order to improve the efficiency of the solar collector, it is proposed to optimize the collector to the effect that it can make better use of the incident solar energy regardless of the position of the sun. One solution is to use trackable collectors, thus always ensuring the optimum setting of the collector Lich to ensure the respective position of the sun. The disadvantage of trackable collectors, however, is that the design of such types becomes extremely complex and costly. Furthermore, trackable and thus movable collectors are susceptible to weather and maintenance.

It is also known solar panels with juxtaposed Insert reflectors in the form of open-top channel profiles, in the longitudinal direction extending line sections for heat transfer medium exhibit. Some of these are preferably in cross section circular Line sections of the absorber with radially projecting, at least essentially over the reflector length extending absorber strip or Absorberstegen provided. So is known for example from AT-402114B, the line sections of the absorber with upwardly or downwardly projecting absorber webs equip, the heat absorption through the line sections for the heat transfer medium especially in case of diffuse radiation. The after cause absorber webs directed down against the reflector wall doing so, that the line sections of the absorber further into the vicinity of the cylinder axis the reflector, so that even at a low angle of incidence of sunlight, the line sections of the absorber are irradiated directly. The disadvantage here is in that, basically a relatively large one Radiation component also indirectly absorbed via the absorber web and thus over a detour is forwarded to the conduit system of the absorber, being at the connection of absorber web and pipe section with large heat losses is to be expected.

From the EP 0033054 A1 It is also known to achieve an improvement in the efficiency of a solar collector by an appropriate design of the shape of the reflectors.

at all is known from the prior art collector designs the heat transfer between the absorber and the conduit system of the absorber the heat transfer medium uneven and therefore incomplete, there with all known solutions the absorbers in the reflector troughs are not everywhere from the sun illuminated and therefore heated unevenly. This leads to a Forming hot and cool Sections on the circumference of the line sections of the absorber, what ultimately to the defective heat transfer to the heat transfer medium leads.

On the basis of the described problem is the present Invention, the object of a solar collector of the beginning Such a way that the heat transfer from the absorber or the line sections of the absorber on the heat transfer medium and thus the entire Efficiency of the solar collector can be significantly improved.

These Task is in a solar collector of the type mentioned solved by in that a device for swirling the heat transfer fluid flowing through the absorber is provided.

The inventive solution has a whole series of significant advantages over those from solar technology known and explained above Collectors on. Through the use of the swirling device becomes the heat transfer fluid within the conduit sections of the absorber that run along of the reflector extend, swirled. This ensures that the heat transfer fluid throughout in a turbulent flow flows through the absorber. The turbulator serves on the one hand to turbulence from an initial laminar flow the heat transfer fluid on the other hand turbulence in one already turbulent flow the heat transfer fluid to maintain (production). Those turbulences cause the from the non-linear dynamics known effects of the turbulent Diffusion. This turbulent diffusion is generally well above the molecular values involved in laminar flows, and in particular in the flow the heat transfer fluids in the line sections of the absorbers known from the prior art, occur. In other words this means that over the swirling device according to the invention generated turbulent flow in the absorber building a boundary layer between the flowing heat transfer fluid and the wall of the absorber is prevented. This will be the Heat transfer significantly improved between the absorber wall and the heat transfer fluid.

One Another advantage of the swirling device is that by forming the turbulent flow in the absorber a pollution of the Inner wall of the absorber or a deposit on this by the Heat transfer fluid can be prevented. Those soiling or deposits lead to the known from the prior art absorbers to another Reduction of heat transfer between the absorber wall and the heat transfer fluid. Because of the engagement the swirling device thus becomes a self-cleaning effect achieved.

The swirling device according to the invention can furthermore be used independently of the respective collector type. For example, it is conceivable that the swirling device is a flat collector to use vacuum flat plate collectors, tube collectors and vacuum tube collectors.

Furthermore can the swirling device according to the invention in an advantageous way for everyone currently conceivable heat transfer fluids be used with the advantages described above. That means, that not just a watery one Heat transfer fluid, but also oils or other easily vaporizable substances as heat or heat transfer fluid be applied, by the swirling device in the flow through the Absorbers are swirled, resulting in the above-mentioned advantages and in particular for optimizing the heat transfer between the absorber and the heat transfer fluid leads. It is also conceivable, the swirling device according to the invention in, for example, vacuum tube collectors use of the heat pipe type. This is an evaporator, where the heat the absorber over closed tube from the glass tube led out and over a wet or dry connection to the heat transfer medium is passed on. It could the swirling device according to the present invention Invention are used, for example, the tethered Heat transfer medium to swirl.

advantageous Further developments of the invention are specified in the subclaims.

So For example, it is provided that the swirling device according to the invention one on at least some areas of the interior wall of the absorber trained profiling is. It would be conceivable, for example, those Walls in the interior of the absorber, which are used to guide or guide the heat transfer fluid serve by the absorber, at least partially with ribs or grooves or radially inward to provide directed webs. Also, pipe sections that are in the Absorber to guide the Heat transfer fluid be used, be designed as a swirl or finned tubes. As a result, the heat transfer fluid flowing through the absorber forcibly into a spirally rotated movement offset. As a result, the laminar steady flow of the Heat transfer fluid superimposed in the absorber a disturbing movement, which is a transition from the laminar to the turbulent flow state and thus the Inserting the turbulence causes. This is done in an advantageous manner called by all Zones of the absorber wall heat optimally derived and better heat dissipation at the absorber or a better heat transfer on the heat transfer fluid reached. It would be conceivable that the intended swirl or finned tube has a multiple pitch, so that the heat transfer fluid in a forced, spiraling motion is transported on the inner wall of the absorber, thus a particularly good heat absorption and optimal heat transfer to enable.

In a particularly advantageous realization of the solar collector according to the invention is further provided that the swirling a from trained at least some areas of an inner wall of the absorber Roughness is. Such roughness could, for example, be the same or differently sized perturbation objects that are called turbulence germs serve. Those disturbing objects are doing on the walls inside the absorber that leads to the line or leadership of the heat transfer fluid serve the absorber, arranged. Because of these disturbing objects specifically targeted to certain areas of the inner wall of the absorber can be trained can the degree of turbulence of the flow Optimal to the respective application, that is to the absorber shaping, the heat transfer fluid, the flow rate, etc., to be adjusted. Of course it is conceivable the roughness in conjunction with one on at least some areas to use the inner wall of the absorber trained profiling. Also here are other obtrusive objects, such as in the flow the heat transfer fluid provided turbulence wires, conceivable.

A advantageous, although partially known from solar technology Further development of the present invention is the the absorber in addition to at least one absorber tube whose one end face is closed is and its other face is open or at least an opening and as an outlet of the heat transfer fluid serves, further arranged in the interior of the absorber tube feed tube for Respectively the heat transfer fluid has, whose two end faces are open or at least each have an opening and their on the outlet side of the absorber tube opening as an inlet of the heat transfer fluid serves. The advantage here is in particular to be seen in that which was covered by the absorber tube Feed tube that Heat transfer fluid the absorber is supplied fluently in a first direction, while that heat transfer fluid subsequently in a second direction opposite to the first direction from the absorber tube over whose outer circumferential surface flows out. These Construction has the advantage that the inlet and the outlet for the heat transfer fluid to The same side of the absorber are arranged, so that on the one hand a very compact design of the absorber is achievable and the another multiple absorber easily connected in a row can be. For constructional reasons If the absorbers are usually made in the form of tubes, this would be conceivable here but also to use flattened or plate-shaped absorber.

When a particularly advantageous development of the latter embodiment is provided that as a delivery tube, the enveloped by the absorber tube is used, a swirl or finned tube is used. This corresponds on the outer surface of the supply tube trained profiling of the swirling device. Thereby is causing the heat transfer fluid, after it about the supply tube supplied to the absorber has been re-flowing by means of on the outer surface of the supply tube trained profiling is swirled. Because of the absorber turbulent flowing back heat transfer fluid will provide optimal heat transfer between the outer wall of the Absorber tube and the heat transfer fluid achieved. Conceivable here would be that the outer wall the absorber ear simultaneously represents the outer wall of the absorber. In another implementation is particularly advantageous provided that the absorber in addition to a transparent casing comprising, which at least the absorber tube with the inner supply tube partially surrounds. For better thermal insulation could the space between the outer wall of the absorber tube and the housing inner wall filled with inert gas be; possible would be, however also to evacuate this gap. By the noble gas filling or the evacuation of the space between the absorber housing and the absorber tube can Advantageously, convection-related heat losses significantly reduced become. Of course In this case, other constructions are conceivable to such losses to minimize.

In a particularly advantageous embodiment of the latter embodiment of the invention it is provided that the vortexing device provided on or in the supply tube is in the shape of circumferential grooves applied by means of a stamping or rolling process were. In this case could for example, the feed tube a thin-walled one Be tube, which with spiral circumferential grooves is provided. This will accomplish that not only on the outer surface of the supply tube a profiling is formed, but also a corresponding corresponding profiling on the inner circumferential surface of this Tube to be found is. The advantage here is, inter alia, that through this execution the feed tube thermal Strains can absorb easily.

Around even at low incidence of light on the reflector of the solar collector according to the invention one possible huge To be able to use fraction of the incident radiation is preferably provided that at least one absorber bar extends radially from the absorber to the outside. That absorber bar improves the heat absorption through the sections, which the heat transfer fluid through the absorber, especially with diffuse radiation. It is envisaged that those radiation components due to the flat incidence by For example, shading the reflector edges were originally no longer used could, indirectly via the Absorber bar recorded and thus forwarded to the absorber become. Conceivable here would be to use one or a variety of absorber bars, which themselves extend from the absorber up or down. Especially Advantageously, a vertical Absorbersteg down or up, or there are two horizontal absorber bars after provided on the right or left, thereby a possible optimal ratio of Absorption, convection and heat radiation related on the absorber surface is reached. Of course But here are other arrangements of Absorberstegen conceivable.

In a possible Realization of the solar collector according to the invention is provided that the absorber is meander-shaped, thus an optimal design adapted to the respective application to enable the solar panel. The meander-shaped absorber shape the swirl tube makes sense especially if, for example flow baffles, Notches or flats arranged in a smooth absorber tube be, as well as swirling to a sufficient extent possible. Of course they are the teachings of the present invention to each collector shape or Absorber form with the same beneficial effects averted.

A advantageous, although also known from solar technology training The present invention is that the reflector of the solar collector a groove profile open in the direction of the incident radiation is. It is provided that the gutter profile the radiation on the Absorber focused. This is done, for example, by mirroring the surface achieved the reflector. It is conceivable here to use reflectors, have the circular cylindrical or parabolic cross sections. Furthermore, it is conceivable, trackable Reflectors in the context of the solar collector of the present Use invention to independently from the direction of incidence of the radiation as optimal an efficiency as possible achieve.

To the Achieving a compact solar collector is further advantageous provided that a plurality of adjacent reflectors are arranged to form a collector array.

Finally, it is in terms of optimal, that is as complete as possible absorption of the collimated in the focal plane of the solar collector Radiation advantageous that the cross section of the formed in the focal plane or its surroundings absorber of the solar collector has a oriented on the Katakaustik circular shape. Advantageously, furthermore, the outside of the absorber is coated with a highly selective absorber foil (for example TINOX). Furthermore, the arrangement of the absorber is optimized within the reflector to the effect that it is arranged in its horizontal position symmetrically to the associated reflector and moved in the vertical direction in the center of Katakaustik. Advantageously, the absorber is arranged in the reflector such that a minimum insulating gap remains between the absorber and the reflector. By this arrangement of the absorber and by the use of oriented on the Katakaustik, circular absorber cross-section, the size of the surface of the absorber on which the reflected radiation from the reflector is collimated, almost independent of the angle of incidence of the radiation. Of course, other arrangements or cross-sectional shapes of the absorber are also conceivable here.

in the Below is a preferred embodiment of the solar collector according to the invention closer to the drawings explained.

It demonstrate:

1 a partially sectioned, perspective view of the connection side of a constructed from three solar panels collector array;

2 a section from 1 , the inlet and outlet of a solar collector according to the invention of 1 represents collector arrays shown;

3 one on the line AA 'in 1 taken sectional view of in 1 shown embodiment of the collector array; and

4 a cross-sectional view of the inventive by a solar collector of 1 shown collector arrays, which illustrates the irradiation of the reflector arranged in the absorber at different angles of incidence of the radiation incident on the outside of the reflector.

1 shows a partially sectioned, perspective view of the connection side of a constructed from three solar panels collector array. That collector array has a housing 11 with thermal insulation, a transparent cover 12 as well as the already mentioned three solar panels, which are in the housing 11 are arranged on. The trough-shaped or box-shaped housing used in the illustrated embodiment 11 is preferably gas-tight through the transparent cover 12 completed. As a transparent cover 12 For example, low-iron solar safety glass is used, which is characterized by a high degree of transmittance for the short-wave spectral range. At the same time, only a little of the heat radiation from the respective absorbers 3 through this glass cover 12 out again. In addition, the transparent cover prevents 12 the heat extraction from the respective absorbers 3 by convection-related heat exchange with, for example, colder air in the environment. The individual solar panels are through the cover 12 and the case 11 furthermore protected against the weather. As typical housing materials aluminum and galvanized steel sheet or even glass reinforced plastic are conceivable.

The individual solar panels are laterally and on their undersides with (not shown) spacers on the housing 11 attached. It is conceivable by means of thermal insulation on the underside of the respective absorber 3 and on the side walls of the housing 11 To reduce heat losses through heat conduction. As a possible insulating materials, for example, polyurethane foam and mineral wool or even mineral fiber insulation materials, such as glass wool, rock wool, glass fiber or fiberglass can be used. Furthermore, it is possible the housing 11 in addition to or instead of filling these insulating materials with inert gas, or to evacuate the housing to effect a corresponding thermal insulation.

At the in 1 illustrated embodiment, solar collectors are used by the so-called pipe in tube type, that is, solar panels whose absorber 3 work in countercurrent process. The construction of the pipe-in-pipe system has the advantage that both the inlet 9 as well as the outlet 7 of every absorber 3 lie on the same side of the absorber, so that several absorbers via a common supply line 13 and a common derivative 14 in series can be switched in series, as in the embodiment according to 1 with the respective absorbers 3 the three individual solar panels is the case. Of course, but also conceivable, the connection of supply and supply line 13 and return 14 also on both sides and not as shown on one side. The attachment of the individual absorbers 3 in the respective solar panels takes place at the opposite end of the inlet or outlet of the absorber by means of a (not shown) holder, wherein the position or position of the absorber 3 relative to the associated reflector 1 is fixed. The holder is designed so that it is the length of the absorber 3 absorbs with temperature change.

Each of the individual absorbers 3 is provided with a selective coating to prevent emission of long-wave radiation. This allows the release of excess heat through the surface of the absorber 3 be reduced or prevented in the form of long-wave heat radiation, so that can reach Absorbiergrade of up to 90%. It would also be conceivable, a titanium nitride oxide layer on the outer surface of the respective absorber 3 to use. A derar term coating is usually applied by vacuum evaporation. It is also conceivable, the outer sides of the respective absorber 3 over the length of the associated reflectors 1 to coat with a highly selective absorber foil.

The particular arrangement of the individual absorbers 3 within the associated reflectors 1 is optimized so that every absorber 3 in its horizontal position symmetrical to the associated reflector 1 is arranged and in the vertical direction in the center of the Katakaustik the associated reflector 1 is moved. In an advantageous manner, however, in principle an insulating gap remains between the absorber 3 and the reflector 1 ,

It is particularly preferred that the respective absorber 3 one at the Katakaustik of the associated reflector 1 oriented, circular cross-sectional shape, so as to have a high and in particular the angle of incidence of the reflector 1 incoming solar radiation to achieve independent efficiency.

The respective reflectors 1 serve to reflect incident radiation such that it is collimated in a focal plane. In this focal plane or at least in their environment is the absorber 3 for absorbing that collimated radiation and converting the energy of the absorbed radiation into heat of absorption. The special mirror geometry of the individual reflectors 1 ensures that direct and diffused sunlight especially at unfavorable angles of incidence on the associated absorber 3 falls. This significantly improves the energy yield. Conceivable here would be, for example, the use of highly reflective, weather-resistant CPC mirrors (compound parabolic concentrator). The radii of the individual reflectors 1 Thus, optimal height, trough number per collector width and weight and manufacturing cost of the solar collector and the collector array can be adjusted.

The individual absorbers 3 be from a heat transfer fluid 4 flows through. By a (not shown) control, the temperature in the solar collector and in a (also not shown) hot water tank, which stores the heat energy collected through the collector array, checked. If the temperature at the solar collector is higher than that in the hot water tank, the heat transfer fluid begins 4 to circulate and heat the water stored in the hot water tank. As heat transfer fluid 4 As a rule, a mixture of water and antifreeze is used; conceivable here would be, for example, a hydrocarbon-based fluid.

2 shows a section 1 that the inlet 9 and outlet 7 of a single solar panel of the in 1 represents shown collector arrays. This excerpt clearly shows that the absorber 3 from an absorber tube 6 and one inside the absorber tube 6 arranged feed tube 8th composed. The absorber tube 6 is on the in the 2 shown end of the absorber 3 opened or has an opening that as an outlet 7 serves. That absorber tube 6 is over the outlet opening 7 with a return 14 connected. The inside of the absorber tube 6 arranged feed tube 8th is in contrast to the absorber tube 6 open on both sides or has an opening on both sides. At the in the 2 shown end of the absorber is the opening of the feed tube 8th as an inlet for supplying the heat transfer fluid 4 in the absorber 3 , That inlet 9 corresponds to a flow pipe system 13 , which is located in the return pipe system 14 located. The respective absorber pipes 6 or supply tubes 8th the Indian 2 not shown) other absorbers are on the same flow pipe system 13 or return pipe system 14 connected with each other.

The feed tube 8th has a profile formed on its outer circumferential surface, which as a swirling device 5 serves. In the illustrated embodiment, this swirling device 5 one the feed tube 8th spiral circumferential groove, for example by means of a rolling process on the feed tube 8th was applied. Because of this swirling device 5 this is done through the absorber tube 6 on the outside of the feed tube 8th to the return 14 returning heat transfer fluid 4 placed in circulation, so that an optimal heat transfer between the heat transfer fluid 4 and the absorber tube heated by the absorbed radiation.

It would also be conceivable that, instead of or in addition to the profiling formed on or in the feed tube, other disruptive bodies would be used as turbulizers 5 used, for example, radially inwardly directed webs.

3 shows one at the line AA 'in 1 taken sectional view of in 1 shown embodiment of the collector array. Here comes clearly the coaxial arrangement of the individual supply tubes 8th in the associated absorber pipes 6 the individual absorber 3 to expression. For a better overview, a complete description of the flow pipe system was provided 13 or return pipe system 14 for the individual absorbers 3 are common, waived. The individual reflectors 1 seamlessly merge into each other at their respective points of contact, giving the collector array additional stability. Furthermore, at the individual absorbers 3 the respective solar panels radially from the individual absorbers 3 outwardly extending absorber webs 10 intended. In the embodiment shown here, the respective absorber webs extend 10 both up and down, so as to absorb as much radiation energy even at obliquely incident radiation, in which case the absorber webs 10 absorbed heat absorbs the absorber 3 is supplied by heat conduction.

4 shows a schematic cross-sectional view through a solar collector according to the invention of 1 shown collector arrays, the irradiation of the reflector 1 arranged absorber 3 at different angles of incidence of the reflector 1 clarifies incoming radiation. The arrangement of the absorber 3 inside the reflector 1 is optimized so that the absorber in the vertical direction in the center of the Katakaustik the reflector 1 is moved. The in the 4 shown schematic view shows that the size of the directly illuminated area on the absorber 3 even at a shallow angle of incidence of the incident radiation changes only insignificantly with respect to the incident at right angles to the cover radiation. Not directly on the absorber 3 incident radiation becomes after reflection at the reflector 1 on the absorber 3 forwarded and for heating the heat transfer medium 4 used.

At This point you pointed out, all the above Parts for seen alone and in any combination, especially those in The details shown in the drawings claimed as essential to the invention become. amendments this is familiar to the person skilled in the art.

1

reflector

2

focal plane

3

absorbe

4

Heat transfer fluid

5

swirling

6

absorber tube

7

Absorber tube outlet

8th

supply tube

9

Supply tube inlet

10

absorber bridge

11

casing

12

cover

13

Flow pipe system

14

Return pipe system

Claims (11)

Solar collector, comprising: - at least one reflector ( 1 ) for reflecting incident radiation and for collimating the reflected radiation in a focal plane ( 2 ); - one in the focal plane ( 2 ) or their environment trained absorber ( 3 ) for absorbing in the focal plane ( 2 ) collimated radiation and for converting the energy of the absorbed radiation into absorption heat; and with - one the absorber ( 3 ) flowing through the heat transfer fluid ( 4 ) for absorbing the heat of absorption, characterized by a device ( 5 ) for swirling through the absorber ( 3 ) flowing heat transfer fluid ( 4 ). Solar collector according to claim 1, characterized in that the swirling device ( 5 ) one on at least some areas of an inner wall of the absorber ( 3 ) is profiled profiling. Solar collector according to claim 1 or 2, characterized in that the swirling device ( 5 ) one on at least some areas of an inner wall of the absorber ( 3 ) is formed roughness. Solar collector according to one of claims 1-3, characterized in that the absorber ( 3 ) comprises: - an absorber tube ( 6 ) whose one end face is closed and whose opposite other end face is open or at least one opening ( 7 ) and as an outlet of the heat transfer fluid ( 4 ) serves; and - one inside the absorber tube ( 6 ) arranged feed tube ( 8th ) for supplying the heat transfer fluid ( 4 ), with both end faces of the feed tube ( 8th ) are open or at least one opening ( 9 ) and wherein the at the outlet side of the absorber tube ( 6 ) opening ( 9 ) as an inlet of the heat transfer fluid ( 4 ) serves. Solar collector according to claim 4, characterized in that the swirling device ( 5 ) one on the outer surface of the feed tube ( 8th ) is profiled profiling. Solar collector according to claim 4 or 5, characterized in that the swirling device ( 5 ) at least one the feed tube ( 8th ) is a spirally encircling groove which, by means of an embossing or rolling process, is applied to the feed tube ( 8th ) was applied. Solar collector according to one of the preceding claims, characterized by at least one radially from the absorber ( 3 ) outwardly extending absorber bar ( 10 ). Solar collector according to one of the preceding claims, characterized in that the absorber ( 3 ) is meander-shaped. Solar collector according to one of the preceding claims, characterized in that the reflector ( 1 ) is an open in the direction of energy irradiation gutter profile. Solar collector according to one of the preceding claims, characterized by a multiplicity of adjoining reflectors ( 1 ) for forming a collector array. Solar collector according to claim 10, characterized by a at the Katakaustik of the reflector ( 1 ) adapted cross-sectional shape of the absorber ( 3 ).