DE102011114348A1 - Free stream flow engine for energy transformation in e.g. gaseous medium, used in e.g. wind power plant, has rotating portions that are propelled on rotor, to produce lift forces changed by rotation of rotor in usable rotation torque - Google Patents

Abstract

The free stream flow engine comprises rotating portions that are propelled on a rotor, for producing liquid, gaseous and plasma medium lift forces. The forces are changed by the rotation of the rotor in a technically usable rotation torque. A bearing of the rotor is designed as a shaft, wheel-rail system, air bag system, or as magnetic levitation system.

Description

The invention describes a flow engine for energy conversion in free-flowing gaseous, plasmatic or liquid media. By means of driven, rotating bodies, buoyancy forces are generated by the Magnus effect according to the Flettner rotor principle. From shadowing in the wake of the profiles and by a reduced flow velocity, with change in the direction of flow on the windward side of the rotor, a difference in force is generated. The supporting rotor disc converts the buoyancy forces, with a lever arm to the rotor axis, according to the Darrieus principle into a technically usable torque. When designing the rotating body as a Flettner rotor with Thom discs so the free-stream can be deflected by friction on maximum profile surface and be used compared to aerodynamic profiles significantly higher buoyancy. Since the Flettner rotors with Thom disks always produce the maximum lift independently of the angle of attack, energy can already be converted from slowly flowing media with changing flow direction with high efficiency. By changing the rotational speed of the rotating body, the performance of the system can be regulated. Conversely, acceleration of the medium is possible when the rotor is driven.

LIST OF REFERENCE NUMBERS

1

rotating body running as Flettner rotor with rounded Thom discs, electric drive not shown

2

Rotor designed as a ring rail

3

annular bearing with bearing rollers, power loss, for example, not shown on integrated ring generator

State of the art

So far, Flettner rotors have been proposed as horizontal wind turbines, see Hanson, US Pat. No. 2,525,772 , Here, the complex aerodynamics of the Flettner rotors offers hardly any advantages over fixed rotor blade profiles due to the high control effort of the rotation. Darrieus rotors have so far only used aerodynamic profiles with an angle of attack of 0 °. US1791731 describes the concept known as Madaras rotor to use Flettner rotors on rail-guided car. The direction of rotation of the Flettner rotors is reversed halfway. However, this is possible only with very large, slowly rotating equipment to have sufficient time in relation to the rotor circulation for braking and accelerating the rotating rollers as a buoyant body. The high speeds required to produce a Magnus effect, with opposite directions of rotation, are difficult to implement technically in systems of realistic dimensions. Ultimately, the requirement of very slow rotation in practice leads to high costs to couple such a system to electric generators. Since the generator corresponding to the diameter of the system is very large, the use of materials is high and correspondingly expensive. The alternative of using a large number of small generators and bearings, with corresponding losses and costs, does not fare any better in this regard. Similarly, the mechanical use of rolling car at a central point is complex. An economic, technical concept for the use of the Madaras rotor could therefore not be found so far.

Advantages of the invention

2 shows, as a possible embodiment of the invention, a rotor according to the Darrrieus principle without a central shaft as a wheel-rail system. Here are different versions possible, such as central mast and shaft or an annular maglev. The power reduction, not shown, in the embodiment shown as a ring generator on the rotor ( 2 ) and storage ( 3 ) getting produced. The attachment of permanent magnets and coils to form a generator magnetic field is not a difficulty.

An essential feature of the invention is the use of Flettner rotors with Thom discs ( 1 ) instead of aerodynamic profiles with fixed or variable angle of attack. In place of the Flettner rotors with Thom disks shown, for ( 1 ) different rotating bodies are used, which are adapted to generate from the outer flow and the wind of rotation of the rotor, a buoyancy force by the rotation of the body.

Since the production of the rotation of the lift-generating body ( 1 ) can be done by direct drive with electric motors, this is not shown executed in detail.

In 1 The vector addition of the wind speeds of a Darrieus rotor using Flettner rotors rather than fixed profiles is shown in theory. 1 shows that, in contrast to the Madaras rotor, a reversal of the sense of rotation of the rotors to produce a force difference is not required and therefore can be omitted as proposed. As a result, a much simplified version of the system is possible, which makes a higher speed of the system possible and is thus suitable to be connected directly to electrical generators for power generation or already implemented with an integrated generator.

By regulating the rotational speed, the buoyancy achieved by the rotating bodies can be adjusted in such a way that a speed of rotation of the rotor relative to the external flow v0 which is favorable for achieving favorable lever arms is achieved. This results in v0 and Vrot by vector addition the flow Vres at the different, exemplarily shown positions of the rotor. By Magnus effect results in a proportional buoyancy force at an angle of 90 ° to the flow of the rotating body, the force direction is defined by the sense of rotation of the roller.

With an aerodynamic profile, lift coefficients of approximately Ca = 3 can be achieved using high-lift propulsion. With a Flettner rotor, lift coefficients of approximately Ca = 12 can be achieved. Thom's research suggests that by using closely staggered disks on the rotor roll of a Flettner rotor, the deflection of the flow can be further maximized, similar to a Tesla pump. As a result, lift coefficients of Ca = 28 can be achieved. The higher lift coefficients make it possible to achieve sufficiently large forces to operate the rotor already at lower flow speeds or smaller system diameters.

The efficient use of the high lift coefficients allows the use of previously not economically accessible slower flows for energy conversion. Likewise, the construction of energy converters in strongly fluctuating or their direction changing currents is possible where rotors in propeller design can not be used or only with great effort. In particular, where high speeds are required for use, the high lift coefficients allow the effective use of gears or generators, with high magnetic resistance, even at low wind speeds compared to other wind turbines.

The design of the system shown allows the construction of cheaper wind turbines. Here, with significantly less use of material and moving parts larger flow areas can be skimmed off. The multi-bearing rollers can be designed as longer profiles and the annular rotor as a rail system with a larger diameter, in contrast to previously built Horizontalachswindkraftanlagen and Darrieus rotors. The elaborate tower structures and rotor blades are replaced by much easier to be manufactured components.

By using simple geometric shapes, the rotor can be made extremely cheap. This can be at low investment cost economic systems, for example for wind power, hydropower or tidal power plants, realize.

By driving the system, a reversal of the operation as a pump, drive or other purposes is possible.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 252572 [0002]
• US 1791731 [0002]

Claims (9)

Free-flow flow machine with rotating bodies on revolving rotor, characterized in that one or more driven, rotating body on a rotor in a liquid, gaseous or plasma medium to generate buoyant forces and the forces are converted by the rotation of the rotor into a technically usable torque. Free-flow flow machine with rotating bodies on revolving rotor, characterized in that, one or more driven, rotating body on a rotor generate buoyant forces and accelerate the forces by driving the rotor, the flow. Free-flow fluid flow machine according to 1) or 2), characterized in that rollers, rollers with end plates, rolls with attached discs or Thom discs, rolls with attached discs with rounded approach to the roller, Tesla pumps, paddle wheels, Savoniusrotoren, Wheels, profiles or similar are used as rotating bodies, with the intention of generating high buoyancy forces. Free stream flow engine according to 1.) or 2.), characterized in that the rotor is designed as a disc or ring and the bearing of the rotor is designed as a shaft, wheel rail system, air cushion system or magnetic levitation system. Free-flow fluid flow engine according to 1.) or 2.) and 3.), characterized in that the rotating bodies are set or kept in rotation electrically, pneumatically, hydraulically, aerodynamically, mechanically or with the circulation of the rotor. 1) or 2) characterized in that the performance of the system and or the direction of the flows is regulated by controlling the rotational speed of the rotating body. Free-flow fluid flow machine according to 1.) or 2.), characterized in that the usability of the system is ensured by cooling or heating of the rotating body or made by painting the rollers or special design of the surface a usability in a particular medium or the deposition of the medium , For example, ice or condensation, is avoided. Free stream flow engine according to 1.) or 2.), characterized in that the operating state of the system is maintained by a controller in a desired operating state. For this purpose, the system is accelerated or braked by the controller, for example by use of 6.) and possibly kept in a safe state for maintenance or emergency shutdown or the like with securing bolts, clamps, locking pins or other suitable mechanical fixings. Free-flow turbomachine according to 1.) or 2.), characterized in that the system is carried out with integrated drive, gearbox, bearing or generator, for example by attachment of magnets or coils or mechanical devices such as blades, sprockets, rollers, drives or the like.

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