EP2646758A2

EP2646758A2 - Solar-radiation receiver, and method for the solar heating of heat transfer medium

Info

Publication number: EP2646758A2
Application number: EP11790961.4A
Authority: EP
Inventors: Reiner Buck; Lars Amsbeck; Marc Röger; Birgit Gobereit; Wei Wu
Original assignee: Deutsches Zentrum fuer Luft und Raumfahrt eV
Current assignee: Deutsches Zentrum fuer Luft und Raumfahrt eV
Priority date: 2010-12-02
Filing date: 2011-11-30
Publication date: 2013-10-09
Also published as: DE102010062367A1; WO2012072677A2; BR112013013532A2; WO2012072677A3

Abstract

The invention provides a solar-radiation receiver comprising a container with a wall and also comprising an interior space, enclosed by the wall, and a rotary-drive device, by means of which the container can be rotated about an axis of rotation, wherein the container has an axis which is oriented parallel, or at an acute angle, to the direction of gravitational force, wherein heat transfer medium can be channelled through the container to form a film of heat transfer medium on an inner side of the wall.

Description

Solar radiation receiver device and method for solar heating of heat transfer medium

The invention relates to a solar radiation receiver device.

Furthermore, the invention relates to a method for solar heating of heat transfer medium, are guided in the heat transfer medium through a solar radiation irradiated container, wherein a heat transfer medium film is formed on a wall of the container.

By a solar radiation receiver device can be heated by solar radiation heat transfer medium such as (solid) particles and in particular ceramic particles to high temperatures, for example up to 1000 ° C.

From WO 2010/015515 A2 a radiation receiver for transmitting the energy of incident solar radiation to solid particles is known, which comprises an inclined plane having at the upper end of an inlet device for cold particles and at the bottom of a drain for hot particles.

From DE 103 43 861 AI a solar-heated industrial furnace with a reaction space is known which has a window for the entry of focused solar radiation, which is directed by a Strayo concentrator through the window in the reaction space, wherein a non-solar heat source is provided, the so is designed so that they can take their energy input in the absence or insufficient performance of the solar radiation. The invention has for its object to provide a solar radiation receiver device, which has an optimized receiver efficiency. This object is achieved in that a container having a wall, an inner space surrounded by the wall and a rotary drive means, through which the container is rotatable about a rotation axis, is provided, wherein the container has an axis which is parallel or in an acute Angle is oriented to the direction of gravity, wherein through the container heat transfer medium to form a heat transfer medium film on an inner side of the wall is feasible.

In the solar radiation receiver device according to the invention, centrifugal forces caused by rotation of the container can form a heat transfer medium film and preferably coherent heat transfer medium film on the wall. The container is acted upon by solar radiation and there is the heating of the heat transfer medium.

By correspondingly fast rotation of the container can be achieved that centrifugal forces push the heat transfer medium to the wall and thus receives an increased wall adhesion. As a result, in turn, the residence time of the heat transfer medium in the container can be increased. Furthermore, the heat transfer medium can thereby obtain a tangential velocity. As a result, the heat transfer medium loss (that is, the passage of heat transfer medium without sufficient heating in the container) can be reduced because heat transfer medium is displaced outwards against the wall. By means of a tangential velocity, it is also possible to achieve a temperature compensation in the circumferential direction, since, for example, different zones in the circumferential direction are repeatedly passed through by the heat transfer medium. This gives a more homogeneous temperature distribution at the exit of the heat transfer medium from the container. The speed is chosen so high that results in an optically dense or nearly dense heat transfer medium film over the entire circumference of the wall. In particular, it is possible to increase the residence time of the heat transfer medium in the interior. This can increase the receiver efficiency.

Temperature gradients in the heat transfer medium film can be compensated and a more homogeneous temperature distribution can thus be achieved.

By appropriate control of the rotation and / or the angle to the direction of gravity can also be a controlled adjustment of the solar radiation receiver device, for example, in partial load operation or full load operation.

A solar radiation receiver device according to the invention can be used, for example, for the exclusive solar operation of high temperature processes such as microturbines for solar power generation. Heated heat transfer medium can be stored easily. It can then be an on-demand service provision.

In order to produce as coherent a heat transfer medium film as possible, the angular position relative to the direction of gravity and the rotational speed of the container are preferably adapted to each other. The adaptation can also include properties of the heat transfer medium and the wall and in particular the friction properties. If, for example, a solar radiation receiver device according to the invention is used in conjunction with a heliostat field, then usually the angle to the direction of gravity is predetermined. If the heat transfer medium type and the wall are then specified, then by appropriate selection or adjustment and, if appropriate, also variable input Position of the rotational speed (or speed) of the heat transfer medium film are generated.

The (geometrical) axis of the container basically has no preferred direction and the term "acute angle" refers to the fact that there is no such preferential direction. The acute angle is the smallest angle of the angle between the axis of the container and the direction of gravity. (If the vessel is assigned a directional axis, for example, oriented between an entrance for particles and exit for particles, then "parallel" also includes antiparallel and "at an acute angle" also includes an obtuse angle.)

In particular, the acute angle is less than or equal to 80 °. The heat transfer medium is formed by particles and / or a fluid (in particular a liquid). The particles are in particular solid particles and in particular ceramic particles. It is also possible that a liquid such as a liquid salt or a salt mixture (such as a mixture of NaN0 ₃ and KN0 ₃ ) is used as the heat transfer medium.

It is favorable if a rotational speed of the container is greater than 80% of the root from the ratio of gravitation constant to an inner radius of the container, wherein the inner radius of the container, if it has different inner radii, in particular the smallest inner radius is used. As a result, an optically dense or approximately dense heat transfer medium film can be achieved over the entire circumference of the wall of the container. It is particularly favorable when the speed is greater than 70% of the speed at which the entire heat transfer medium adheres to the wall.

In particular, a device for influencing the movement characteristic of the heat transfer medium in the interior is provided. examples For example, provided for a correspondingly fast rotation of the container, so that the centrifugal force pushes the heat transfer medium against the wall. This gives increased wall adhesion or increased wall friction to increase the length of stay. The duration of stay can for example also be defined or controlled by vibrations and / or by providing special running paths. It is then possible to achieve a greater temperature spread between the inlet and outlet of the heat transfer medium to the container and thereby the receiver efficiency can be increased.

In particular, the device for influencing the movement characteristic is designed as a device for controlling and in particular variably controlling the residence time of the particles in the interior space. As a result, the efficiency can be increased, wherein an adaptation to changing conditions such as changing solar irradiation conditions is possible.

In particular, the axis of rotation is oriented parallel or at an acute angle less than or equal to 80 ° to the direction of gravity. This gives an optimized efficiency. The axis of rotation can in principle also be offset with respect to the axis of the container.

In one embodiment, the axis of rotation is oriented coaxially with the axis of the container.

It is favorable if the rotation of the container is variably variable in time in order to adapt to different conditions and in particular to carry out solar irradiation conditions in order to enable, for example, also different partial load operations.

There may be provided a vibration device through which the container or one or more portions of the container are vibratable. This allows, for example, a tangential velocity component for Generate heat transfer medium. In particular, by a combination of rotation with a suitable rotational speed can set a defined residence time or it can be the residence time control. Furthermore, a residence time can also be adjusted relatively accurately locally. The vibration device can be an additional device and / or the imbalance of a drive is used to generate vibrations.

It can thereby be achieved, for example, a promotion of heat transfer medium against the direction of gravity within the container.

In particular, the vibration device is designed so that the container or one or more portions of the container along the axis of the container are vibratable and / or a spatial position of the axis is temporally variable. It can then be carried out, for example, a tumbling motion.

For example, a vibration of the heat transfer medium against gravity is possible because they are used especially when used as a heat transfer medium particles, provides for a "fluidization". This is particularly advantageous when the container has sloping walls, that is, when the diameter varies over a longitudinal axis of the container.

It can be provided, for example, that the vibration device is designed so that the vibration is temporally and / or spatially controllable. This makes it possible, for example, to adapt the heat transfer medium throughput time through the container to different solar irradiation conditions. In one embodiment, facing the interior, the wall has one or more defined running paths or one or more guide elements for heat transfer medium. By one or more running paths or guide elements, the heat transfer medium is on a specific Path is guided within the container and / or the film formation is improved. With appropriate design of the web or the guide elements, the travel path for passing through the container can be increased and thereby the length of stay of the heat transfer medium in the container can be increased. Furthermore, this can be the heat transfer medium imprint a tangential velocity component.

In particular, a running path or guide element has web elements which lie in a plane perpendicular to the axis of the container or at an angle of at most 30 ° to this plane. Heat transfer medium contacts the web elements. The railway elements provide a guide. If the web elements lie in a plane perpendicular to the axis of the container or at an angle of at most 30 ° to this plane, then it is possible, for example, to impart a tangential velocity component to the heat transfer medium. Furthermore, the travel within the container can be increased.

In particular, the one or more running paths or the guide elements or a tangential alignment to the wall. As a result, the heat transfer medium can be given a tangential velocity component.

For example, steps and / or grooves and / or ribs and / or dents and / or wall roughnesses are formed on the wall. As a result, the film formation can be improved and the residence time in the interior can be increased.

In one embodiment, the device for influencing the movement characteristic comprises a field generating device for generating an electric field and / or magnetic field, wherein the heat carrier medium comprises particles and wherein the particles are electrically and / or magnetically charged. Lorentz forces can thereby be formed (if the particles are electrically charged and a magnetic field acts on them) or electrostatic forces (if the particles are electrically charged and electric particles). acting on them), through which, with suitable training, the particles will move outward towards the wall. These are thereby pressed against the wall. This can increase the length of stay. It is also possible, for example, to influence the residence time for magnetically charged particles by appropriate choice of the Curie temperature. For example, if the Curie temperature is reached within the container or when the container exits, then no magnetic coupling of the particles is more to the corresponding field and the particles can then be easily removed from the container. The force between the field generator field and the magnetically charged particle is effectively turned off intrinsically at the Curie temperature.

It is particularly advantageous if an envelope of the wall on the interior has a varying cross-section and in particular is conical. As a result, the wall is on all sides with respect to the envelope of an inclined plane on which the heat transfer medium can slide along or flow. In particular, the interior tapers in the direction of gravity, so that the container is funnel-shaped. The Solarstrahlungsbeaufschlagung takes place in particular via one side of the container, which has the smaller diameter. It is advantageous if the container has a coupling region for heat transfer medium and a coupling region for heat transfer medium. In one embodiment, the coupling region is located above the coupling-out region with respect to the direction of gravity. At the coupling area "cold" heat transfer medium is coupled and at the coupling-out area "hot", heated by solar radiation heat transfer medium is decoupled. The heat transfer medium is carried out against the direction of gravity through the container. It is also possible in principle for the heat transfer medium to be guided against the direction of gravity in the container, that is to say the heat transfer medium is coupled to the container at the bottom in relation to the direction of gravity and is coupled out in relation to the direction of gravity. This can be achieved in particular by a combination of vibration and rotation with the appropriate rotational speed and, if appropriate, corresponding wall formation (in particular via an inclined wall). It is favorable if a supply device for heat transfer medium to the container is provided, with which heat transfer medium can be supplied to the container at an adapted peripheral speed. As a result, with a corresponding setting of the circumferential speed during the coupling of the heat transfer medium into the container, the film formation can be minimally disturbed by the feed. The supply device is in particular connected upstream of an adjustment device for the mass flow of the heat transfer medium. Both mass flow and peripheral speed can then be set individually. For the same reason, it is favorable if a discharge device for heat transfer medium is provided by the container, with which heat transfer medium with an adapted peripheral speed can be discharged from the container. As a result, the film formation is minimally disturbed by the discharge.

The invention is further based on the object to provide a method of the type mentioned, which results in an optimized receiver efficiency. This object is achieved in the method mentioned in the present invention in that the container is rotated about an axis of rotation which is parallel or at an acute angle to the direction of gravity and / or the container is vibrated. The method according to the invention has the advantages already explained in connection with the solar radiation receiver device according to the invention.

Further advantageous embodiments have also already been explained in connection with the device according to the invention. The method according to the invention can be carried out in particular on the device according to the invention.

In particular, the acute angle is less than or equal to 80 °.

In particular, the heat transfer medium is irradiated directly in the container. Solar radiation is coupled in particular at an underside of the container in the container.

It is advantageous if the container has an axis which is aligned parallel to the direction of gravity or at an angle of less than 80 ° to the direction of gravity. As a result, an optimized efficiency can be achieved.

It is advantageous if the container is vibrated with respect to an axis of the container and / or the spatial position of the axis is changed. As a result, the movement characteristics of the heat transfer medium in the container can be selectively influenced, in particular to increase the receiver efficiency and / or to be able to adapt to changing conditions and in particular solar irradiation conditions.

It can be provided that the heat transfer medium comprises particles and the particles are electrically and / or magnetically charged and an electric field loading and / or magnetic field loading of the particles takes place. As a result, appropriate forces can be exerted on the particles, which press them against the wall of the container, for example, in order to increase the length of stay. In particular, the application of force is such that the particles are forced in the direction of the wall. In one embodiment, magnetic particles are selected so that the Curie temperature is at or below a desired temperature that is reached in the container. When the Curie temperature is reached, so to speak, the magnetic charge of the particles disappears and the corresponding force is then no longer effective. As a result, a coupling of the particles can be achieved in a simple manner. For example, the Curie temperature corresponds to the target temperature for the decoupling.

It is favorable if a movement characteristic of the heat transfer medium is influenced so that the residence time of the heat transfer medium in the container is increased. This results in an increased receiver efficiency.

It is also advantageous if the residence time of the heat transfer medium in the container is adapted to variable load requirements. This gives a variable adjustment of full load operation and partial load operation and adaptation to changing solar irradiation conditions is possible.

In one embodiment, heat transfer medium is conveyed as a partial flow or total mass flow counter to the direction of gravity. This can be achieved in particular by a combination of vibration and rotation with a suitable rotational speed. In particular, the rotational speed is increased to increase a conveyance against the direction of gravity. Under certain circumstances, inclined walls, as they are present, for example, in a funnel-shaped design of the container, are also advantageous. This can be increased in particular by forming an advantageous temperature profile of the receiver efficiency. In particular, in contrast to the direction of gravity, the inlet and the outlet are interchanged with respect to the conventional transport direction. The following description of preferred embodiments is used in conjunction with the drawings for further explanation of the invention. Show it :

Figure 1 is a schematic representation of an embodiment

a solar thermal power plant; a schematic representation of a first embodiment of a solar radiation receiver device according to the invention;

Figure 3 is a schematic representation of a second embodiment of a solar radiation receiver device; and

Figure 4 is a schematic representation of a third embodiment of a solar radiation receiver device.

An exemplary embodiment of a solar thermal power plant, which is shown schematically in FIG. 1 and designated therein by 10, comprises a heliostat field 12 having a plurality of heliostats 14. A heliostat 14 has a mirror surface 16 which can be aligned about at least one axis. Solar radiation 18 can be focused on the mirror surfaces 16 of the heliostat 12 to a solar radiation receiver device 20 in particular bundled. Solar radiation directed at the solar radiation receiver device 20 is indicated by reference numeral 22 in FIG.

In the exemplary embodiment shown, the solar thermal power plant 10 comprises (at least) a tower receiver 23, in which the solar radiation receiver device 20 is arranged on a tower 21 at a distance from a floor 24 (with respect to the direction of gravity g), that is to say it is elevated. The heliostats 14 are also disposed on the floor 14. The solar radiation receiver device 20 is a particle solar radiation receiver device which is operated with particles as a heat transfer medium. The particles are, for example, ceramic particles. In one embodiment, bauxite particles having typical diameters between 0.3 mm to 1 mm are used.

The solar thermal power plant 10 for this purpose comprises a first circuit 26, which is a particle cycle. In this first cycle 26, particles are passed through a heat exchanger 28. The first circuit 26 has a high-temperature branch 30 and a low-temperature branch 32. The low-temperature branch 32 leads from an output 34 of the heat exchanger 28 to an input 36 of the (particle) solar radiation receiver device 20. The high-temperature branch 30 leads from an output 38 of the solar radiation receiver device 20 to an input 40 of the heat transmitter 28. Particles can be thereby via the low-temperature branch 32 of the solar radiation receiver device 20 and are heated there by solar radiation. Heated particles can be supplied via the high-temperature branch 30 to the heat exchanger 28 and can deliver heat there to a second circuit 42.

It may be provided that in the low-temperature branch 32, a heat storage 44 (low-temperature heat storage) is arranged.

Alternatively or additionally, it is possible for a heat store 46 (high-temperature heat store) to be arranged in the high-temperature branch 30.

The second circuit 42 is a turbine circuit. In it, a turbine 48 and in particular steam turbine is arranged, which is coupled to an electric generator 50 for generating thermal power.

The second circuit 42 comprises a high-temperature branch 52, which leads from an output 55 of the heat exchanger 28 to the turbine 48. Furthermore, the second circuit 42 comprises a low-temperature branch 54, wel rather, leads from the turbine 48 or turbine-downstream condenser 56 to an inlet 58 of the heat exchanger 28.

In particular, a pump 60 is arranged in the low-temperature branch 54, which conveys a fluid through the second circuit 42.

At the heat exchanger 28 (in particular water) steam is generated in the fluid of the second steam circuit 42. This steam is fed into the high temperature branch 52 of the turbine 48 for relaxation. At the turbine 48 thermal energy is converted into mechanical energy, which drives the electric generator 50 to generate electricity.

The steam is released and the condenser 46 is condensed to water. This condensate is returned to the heat exchanger 28 in the low-temperature branch 54 for renewed steam generation. In the embodiment shown, a single-stage turbine arrangement is shown. It is also possible that the turbine arrangement is multi-stage.

Alternatively or in addition to the power generation, it is also possible, for example, for a solar radiation receiver device to be used to generate process heat or to effect chemical conversions or to produce fuels. Other applications are conceivable.

A first exemplary embodiment of a (particle) solar radiation receiver device according to the invention, which is shown in FIG. 2 and designated there by 62, comprises a container 64 with a wall 66. The wall 66 surrounds an interior 68 of the container 64.

In the following, the construction and the function of the solar radiation receiver device in connection with particles as heat transfer medium will be described. It is also possible in principle for fluids and in particular liquids, such as molten salts, to be used as the heat transfer medium. The container 64 has an axis 70, wherein in particular an inner side 72 of the container 64 is formed at least with respect to an envelope rotationally symmetrical to the axis 70.

The axis 70 is oriented parallel to the direction of gravity g or lies at an acute angle to the direction of gravity g, this acute angle is at most 80 °. It is usually specified by the orientation of heli-state 14.

The inside 72 of the container 64 is formed by a corresponding inner side of the wall 66. The container 64 is funnel-shaped; of the

Interior 68 tapers from a top 74 to a bottom 76. At the bottom 76, which lies relative to the direction of gravity g below the top 74, the container 64 has an opening 78, which is in particular circular. Solar radiation 22 is coupled via the opening 78 in the container 64; the heliostats 14 of the heliostat 12 direct the solar radiation 22 to the opening 78. The container 64 has at the top 74 an opening 80, which is also preferably circular.

The opening 80 has a larger diameter than the opening 78. Particles 82 are guided via an insertion region 84 into the interior 68 of the container 64. In this case, this coupling-in region 84 comprises or is formed by the opening 80 and is formed by the inlet 36 or is in communication therewith in fluid-effective communication with the particles. Via the coupling-in region 84, "cold" particles 82 are introduced into the interior 68 of the container 64.

Via a coupling-out region 86, which comprises the opening 78 and is formed by this, and which is formed by the outlet 38 or with this compound which is fluidically active for the particles

Particles 82 removed and fed to the heat exchanger 28.

The particle solar radiation receiver device 62 is embodied and operated in such a way that an as coherent particle film as a heat transfer medium film can form on the inside 72 of the wall 66. The particles 82 slip on the inner side 62 from the coupling region 84 to the coupling-out region 86 and are in particular directly irradiated and heated by the solar radiation 22.

A device 88 for influencing the movement characteristic is provided which ensures, in particular, that the falling film is not thinned too much and that a high residence time in the interior 68, that is to say a high residence time for the application of the solar radiation, is achieved. Alternatively or additionally, the device 88 can be used to control the heat absorption of the particles into the container 64 in order, for example, to adapt to varying load conditions (for example due to different solar irradiation). In one embodiment, the device 88 includes a rotary drive device 90 through which the container 64 is rotatable about a pivot axis 92. The axis of rotation 92 is aligned parallel to the direction of gravity g or lies at most at an acute angle of 80 ° or less to the direction of gravity g. In particular, the axis of rotation 92 coincides with the axis 70.

The device 88 may include a vibrator 94 through which the container 64 is vibratable (indicated by reference numeral 96 in FIG. 2). The vibration can be such that, for example, the container 64 rotates along its axis 70. It is alternatively or additionally possible that, for example, the spatial position of the axis 70 is changed in an oscillating manner by the vibration. For example, the container 64 may perform a kind of wobbling motion. In one embodiment, the device 88 comprises a field generating device 98 for generating an electric field and / or magnetic field, with which the interior space 68 can be acted upon. In this case, the particles 82 are electrically and / or magnetically charged.

If, for example, the particles 82 are electrically charged and the field generating device 98 generates a magnetic field, then the particles 82 experience a Lorentz force in the magnetic field, with the particles being moved outward in the direction of the inside 72 of the wall 66 if the magnetic field is oriented accordingly can.

For example, if the particles 82 are electrically charged and the field generating device 98 generates an electric field, electrostatic forces can also cause it to move outward.

If, for example, the particles 82 are magnetically charged, then an outward movement toward the wall 66 can also be effected by an electric and / or magnetic field. It is also possible to select the particles so that the Curie temperature is at or below a target temperature (outlet temperature) of the particle solar radiation receiver device 62. When the corresponding Curie temperature is reached, the particles 82 lose their magnetic charge and the force generated by the field generator 98 decreases. As a result, corresponding particles 82 can be removed in a simple manner. As a result, the effect of the field-generating device 98 on the particles 82 is effectively switched off.

The method according to the invention works as follows:

To be heated "cold" particles are coupled via the coupling region 84 in the container 64. There they are acted upon by the opening 78 forth with solar radiation 22 and heated. The axis 70 is parallel to the direction of gravity g or at most inclined at a small acute angle (in particular less than 80 °) to the direction of gravity g. The container 64 is funnel-shaped.

Measures can be taken via the device 88 in order to "hold" the particles 82 on the wall 66 and, if appropriate, also to control them variably. With appropriate implementation of the method, it is even possible in principle to convey particles 82 (as a partial flow or total mass flow) counter to the direction of gravity g (indicated by the reference numeral 100 in FIG. 2).

The container 64 is rotated. The rotation is so fast that the particle film due to centrifugal forces and particle-wall friction on the inside 72 of the wall 66 can form. The container 64 is rotated so fast that results in an optically dense particle film over the entire circumference of the wall. In particular, the speed is selected so that it is greater than 70% of the speed at which all particles 82 adhere to the wall 66. In particular, the speed (in units of rad / s) is greater than 80% of the ratio of the root of the gravitational constant g to that

1

Inner radius R of the wall 66: n> 0.8 (gl R) ² .

Due to the rotation of the container an increased wall adhesion or edge friction is generated; the centrifugal force pushes the particles 82 against the inside 72 of the wall 66. This can increase the length of stay.

If a vibration is superimposed on the rotation, a delivery against the direction of gravity g can be achieved, at least for a partial flow, in particular if the wall 66 is designed accordingly (see below).

It is also possible for the vibration and / or rotation to be varied over time in order in particular to obtain a tangential velocity component. witness. Also, this can be achieved against the direction of gravity g in particular with a suitable inclination of the axis 70 to the direction of gravity g. By appropriate variable control of the rotation and / or vibration can also be adapted to changing load conditions, in particular due to different solar irradiation conditions.

Alternatively or additionally, by corresponding application of force to electrically and / or magnetically charged particles 82, the field-generating device 98 can influence the movement characteristic and, in particular, increase the residence time in the container 64.

By means of the device 88, for example, the "falling speed" (axial passage speed) of the particles 82, which form the particle film, can be reduced and, in particular, reduced in a controlled manner. A tangential component can be applied to the particle velocity. Particles 82 can be controlled to the inside 72 lead. There is a deceleration by friction to increase the length of stay.

It is preferably provided that the supply and the discharge of the particles takes place at a speed which corresponds at least approximately to the peripheral speed of the container 64. If the feeding is done accordingly, then it is prevented that the film formation is made difficult due to the feeding process. If the circumferential velocity is included in the removal of the particles, then an excessive deviation of the particles from their movement characteristics within the container is avoided. In turn, a disturbance of the film formation due to removal is minimized. Furthermore, then abrasion losses are minimized in the discharge and delivery.

A further embodiment of a particle solar radiation receiver device, which is shown in Figure 3 in a partial view and there with 102 includes a container 104. The container 104 in turn has a wall 106 which defines an inner space 108 and thereby surrounds the interior. An envelope of an inner side 110 of the wall 106 tapers from a coupling-in region 112 to a coupling-out region 114. The coupling-in region 112 lies above the coupling-out region 114 with respect to the direction of gravity g. Solar radiation 22 is coupled into the inner space 108 via the coupling-out region 114.

The container 104 has an axis 116, wherein in particular the inside of the wall 110 with respect to its envelope is rotationally symmetrical to the axis 116.

In the embodiment shown, the axis 116 is slightly inclined (at an angle less than or equal to 80 °) with respect to the direction of gravity g.

On the wall 106, a device 118 for influencing the movement characteristic of particles 82 is formed, which are introduced via the coupling-in region 112 into the inner space 108. This device 118 comprises (at least) a running path 120 or guide element on the inner side 110 of the wall 106.

A track 120 has guide elements 122 supported by soft particles 82, a track element 122 being oriented parallel to a plane 124 which is perpendicular to the axis 116 or at a small acute angle, in particular less than or equal to 30 ° to this axis 116 is located.

By such running paths 120 and guide elements, which are formed by a profiling of the wall 106 on the inner side 110, the residence time of particles 82 in the inner space 108 can be increased, since the axial passage speed is reduced or the residence time is increased. This can be achieved in combination with a rotation and / or vibration and / or field generation, as described in connection with the particle solar radiation receiver device 62. By way of one or more running paths 120 or guide elements, which in particular have a tangential alignment at least component-wise in order to force a tangential velocity component of the particles 82 during the movement on the inner side 110 of the wall 106, the residence time of the particles 82 in the inner space 108 can be increased.

In the exemplary embodiment shown in FIG. 3, the travel paths 120 or guide elements are formed by steps 126 on the inside of the wall 106. In this case, a plurality of spaced-apart steps 126 are provided, wherein the steps 126 are aligned in particular parallel to one another.

The running paths 120 or guide elements can for example also be formed by grooves, ribs, dents, wall roughness, etc.

The steps 126 of the container 104 are spaced from one another. It is also possible for one or more running paths 120 or guide elements to be present, which pass through at least a portion of the container 104 and thereby have an axial extension with a component parallel to the axis 116. The solar radiation receiver device 110 is operated as described above.

If a tangential velocity component is generated for the particles 82 in the inner space 68 or 108, then particle losses can be reduced, that is to say the proportion of those particles which have a reduced radiation exposure and are therefore not sufficiently heated is reduced. The tangential velocity component becomes particles 82 again forced outward to the inside 110 of the wall 106.

In principle, a temperature gradient can arise in the film of the particles 82 in the inner space 108. A tangential velocity component leads to a temperature compensation in the circumferential direction, since in particular different zones in the circumferential direction are passed through several times. As a result, the temperature distribution for the particle temperature is more homogeneous when the particles are coupled out.

In a further embodiment of a (particle) solar radiation receiver device, which is shown in FIG. 4 and designated therein by 128, a container 130 having an axis 132 is provided. The axis 132, which is a longitudinal axis, is inclined at an angle to the direction of gravity g. The angle is, for example, at 45 °.

The container 130 is rotatable about an axis of rotation which, for example, coincides with the axis 132. Furthermore, it is optionally vibratable. The container 130 has a feed end 134 for (cold) heat transfer medium and a discharge end 136 for (hot) heat transfer medium. Solar radiation 18 is coupled into the container 130 in the region of the discharge end 136. It can be provided that a partial flow or a total mass flow of heat transfer medium in the container 130 is conveyed against the direction of gravity.

The container 130 is associated with a feed device 138 for heat transfer medium. The latter is seated at the feed end 134. The feed device 138 is funnel-shaped with a first end 140 and a second end 142. Via the first end 140, the feed device 138 sits at the feed end 134. The device 138 at the second end 142 is smaller than at the first end 140.

The supply device 138 is in particular at least partially designed as a heat exchanger; It is exposed to solar radiation and / or thermal radiation from other components. The corresponding heat can be used. In one embodiment, correspondingly applied walls are at least partially made of a material of high thermal conductivity (in particular metallic thermal conductivity). Via the walls a thermal contact with a heat transfer medium is realized. The walls may additionally be provided with a surface enlarging structure such as ribs, fins, etc. The surface-enlarging structure can simultaneously have a guiding function for particles. This results in a compact design optimized efficiency.

The supply device 138 is designed such that heat transfer medium and in particular particles can be supplied to the container 130 at a peripheral speed, which is optimized for the film formation in the container 130.

It may further be provided a discharge device, which is arranged in the region of the discharge end 136.

A solar radiation receiver device according to the invention can be used in a solar thermal power plant or, for example, also for the provision of process heat. In particular, it can be used when high process temperatures are present and in particular a small to medium power is delivered. An application such as a solar thermal power plant advantageously has one or more reservoirs, each having at least one container which is thermally insulated and in which hot particles are collected. LIST OF REFERENCE NUMBERS

Solar thermal power plant

Heliostat field

heliostat

mirror surface

solar radiation

Solar radiation detector device

tower

solar radiation

tower receiver

ground

First cycle

Heat exchanger

High-temperature branch

Low-temperature branch

output

entrance

output

entrance

Second cycle

heat storage

turbine

Electric generator

High-temperature branch

Low-temperature branch

output

capacitor

entrance

pump

Solar radiation detector device container

wall

inner space

axis

inside

top

bottom

opening

particle

coupling-

output region

Device for influencing the movement characteristic Rotary drive device

axis of rotation

vibrator

"Vibration"

Field generating device

Promotion against the direction of gravity

Particle solar radiation receiver device

container

wall

inner space

inside

coupling-

output region

axis

Device for influencing the motion characteristic Lauf pf ad

orbital elements

level

step

Solar radiation detector device 130 containers

132 axis

134 feeding end

136 exit end

138 feeding device

140 First End

142 Second End

g gravitational constant

R Inner diameter of the container

Claims

claims

A solar radiation receiver apparatus comprising a container (64; 104) having a wall (66; 106), an interior (68; 108) surrounded by the wall (66; 106), and rotary drive means (90) through which the container (64; 104 ) is rotatable about an axis of rotation (92), the container (64; 104) having an axis (70; 116) oriented parallel or at an acute angle to the direction of gravity (g), and wherein the container (64; 104) heat transfer medium (82) to form a heat transfer medium film on an inner side (72; 110) of the wall (66; 106) is feasible.

Solar radiation receiver device according to claim 1, characterized in that the acute angle is less than or equal to 80 °.

Solar radiation receiver device according to claim 1 or 2, characterized in that the heat transfer medium by particles (82) and / or a fluid and in particular liquid is formed.

Solar radiation receiver device according to one of the preceding claims, characterized in that a rotational speed of the container

1

(64; 104) is greater than 80% of (g / R) ² , where g is the gravitational constant and R is an internal diameter of the container (64; 104).

Solar radiation receiver device according to one of the preceding claims, characterized by a device (88) for influencing the movement characteristic of the heat transfer medium in the interior space (68, 108).

6. solar radiation receiver device according to claim 5, characterized in that the means (88) for influencing the movement characteristic is designed as a device for increasing the residence time.

7. solar radiation receiver device according to claim 5 or 6, characterized in that the means (88) for influencing the movement characteristic as a means for controlling and in particular variable control of the residence time of the fluid in the interior (68, 108) is formed.

8. solar radiation receiver device according to one of the preceding claims, characterized in that the axis of rotation (92) is parallel or at an acute angle less than or equal to 80 ° to the direction of gravity (g).

A solar radiation receiver device according to any one of the preceding claims, characterized in that the axis of rotation (92) is coaxial with the axis (70; 116) of the container (64; 104).

10. solar radiation receiver device according to one of the preceding claims, characterized in that the rotation of the container (64; 104) is variable in time controllable.

Solar radiation receiver device according to one of the preceding claims, characterized by a vibration device (94) through which the container (64; 104) or one or more subregions of the container (64; 104) are vibratable.

A solar radiation receiver device according to claim 11, characterized in that the vibration means (94) is formed so that the container (64; 104) or one or more portions of the container (64; 104) along the axis (70; 116) of the container (64; 104) are vibratable and / or a spatial position of the axis (70; 116) is time-changeable.

13. solar radiation receiver device according to claim 11 or 12, characterized in that the vibration device (94) is formed so that the vibration is temporally and / or spatially controllable.

14. solar radiation receiver device according to one of the preceding claims, characterized in that the wall (106) facing the interior (108) one or more defined running paths (120) and / or guide elements (120) for heat transfer medium.

A solar radiation receiver device according to claim 14, characterized in that a track (120) or guide element comprises track elements (122) lying in a plane (124) perpendicular to the axis (116) of the container (104) or at an angle of at most 30 ° to this plane (124) lie.

16. solar radiation receiver device according to claim 14 or 15, characterized in that the one or more of the running paths (120) or the guide elements or a tangential alignment with the wall (106).

17. Solar radiation receiver device according to one of the preceding claims, characterized in that on the wall (106) of the container (104) steps (126) and / or grooves and / or ribs and / or dents and / or wall roughness are formed.

18. solar radiation receiver device according to one of claims 5 to 17, characterized in that the means (88) for influencing the movement characteristic comprises a field generating means (98) for generating an electric field and / or magnetic field, wherein particles (82) as a heat transfer medium electrically and / or magnetically charged.

19. Solar radiation receiver device according to one of the preceding claims, characterized in that an envelope of the wall (66; 106) on the interior (68; 108) has a varying cross-section and is in particular conical.

20. solar radiation receiver device according to one of the preceding claims, characterized in that the interior (68; 108) in the direction of gravity (g) tapers.

21. Solar radiation receiver device according to one of the preceding claims, characterized in that the container (64; 104) has a coupling region (84) for heat transfer medium and a coupling region (86) for heat transfer medium, wherein the coupling region (84) with respect to the direction of gravity (g) is above the outcoupling region (86).

22. Solar radiation receiver device according to one of the preceding claims, characterized by a feed device (138) for heat transfer medium to the container (130), with which heat transfer medium at an adapted peripheral speed of the container (130) can be fed.

23. Solar radiation receiver device according to one of the preceding claims, characterized by a discharge device for

Heat transfer medium from the container (130), with which heat transfer medium with an adapted peripheral speed from the container (130) can be discharged.

24. Process for the solar heating of heat transfer medium, wherein

Heat transfer medium is guided through a solar radiation-loaded container in which by centrifugal force a heat transfer medium film is formed on a wall of the container, characterized in that the container is rotated about an axis of rotation which is parallel or at an acute angle to the direction of gravity and / or Container is vibrated.

25. The method according to claim 24, characterized in that the acute angle is less than or equal to 80 °.

26. The method according to claim 24 or 25, characterized in that the heat transfer medium are irradiated directly.

27. The method according to any one of claims 24 to 26, characterized in that the container has an axis which is aligned parallel to the direction of gravity or at an angle less than 80 ° to the direction of gravity.

28. The method according to any one of claims 24 to 27, characterized in that the container is vibrated relative to an axis of the container and / or the spatial position of the axis is changed.

29. Method according to the preamble of claim 24 or one of claims 24 to 28, characterized in that the heat transfer medium comprises particles which are electrically and / or magnetically charged and an electric field application and / or magnetic field loading of the particles takes place.

30. The method according to claim 29, characterized in that the application of force is such that the particles are forced in the direction of the wall.

31. The method according to claim 29 or 30, characterized in that

magnetic particles are selected so that the Curie temperature is at or below a desired temperature, which is achieved in the container.

32. The method according to any one of claims 24 to 31, characterized in that a movement characteristic of the heat transfer medium is influenced so influ- that the residence time of the particles is increased in the container.

33. The method according to any one of claims 24 to 32, characterized in that the residence time of the heat transfer medium in the container is variably adapted to the load requirements.

34. The method according to any one of claims 24 to 33, characterized in that heat transfer medium is conveyed in the container against the direction of gravity.