CN103940120B - A kind of high temperature solar air heating apparatus - Google Patents

Abstract

A high-temperature solar air heating device relates to an air heating device. The invention aims to solve the problem that the high-temperature heat utilization of solar energy is limited due to the low heat exchange efficiency of the solar heat absorber. Three layers of cylinders with different diameters are coaxially arranged, and two air inlet holes are processed on the outer wall of the outermost cylinder, and two annular chambers are formed between the three layers of cylinders with different diameters. The three annular chambers communicate with each other, and three circles of through holes are sequentially processed along the axial direction on the innermost cylinder wall; three annular ceramic heat-absorbing cores with the same inner diameter, a cylindrical porous ceramic heat-absorbing core and three inner diameters The successively tapering annular ceramic heat-absorbing cores are sequentially embedded in the heat-absorbing shell along the length direction of the heat-absorbing shell, and the three circles of through holes on the innermost cylindrical wall are connected with the three circular rings with the same inner diameter. The ceramic heat-absorbing cores are set correspondingly, and the three ring-shaped ceramic heat-absorbing cores whose inner diameters gradually shrink from the inside to the outside are arranged gradually. The invention is used for solar air heating.

Description

A high temperature solar air heating device

technical field

The invention relates to a high-temperature solar air heating device, which belongs to the technical field of solar energy applications.

Background technique

The solar energy resource is abundant, clean and easy to obtain. The high-temperature solar heat utilization system uses solar concentrators to obtain high-power concentrated energy flow. The volumetric heat absorber adopts a closed and sealed structure to convert the received concentrated solar radiation into heat energy and transfer it to heat It has been widely used in solar thermal demonstration power plants in foreign countries. The radiation convective heat transfer of porous ceramic materials inside it can make the heated air medium generate a high temperature of up to 1000 ° C. However, the heat absorption of domestic solar heat absorbers The thermal effect has not been so obvious, and the expected effect is not always achieved. The heat transfer medium cannot be raised to a higher temperature, and the heat transfer efficiency is low, which limits the development of high-temperature heat utilization technology of solar energy. This is The urgent need to solve the key technologies in high-temperature solar heat conversion makes the development of high-performance solar high-temperature heat absorbers particularly important.

To sum up, the heat exchange efficiency of existing solar heat absorbers is low, which limits the development of high temperature heat utilization technology of solar energy.

Contents of the invention

The invention aims to solve the problem that the low heat exchange efficiency of the existing solar heat absorber leads to the limitation of the development of high-temperature heat utilization technology of solar energy, and further provides a high-temperature solar air heating device.

The technical scheme that the present invention takes for solving the problems of the technologies described above is:

The high-temperature solar air heating device of the present invention includes a secondary concentrator, a first end cover, a first graphite gasket, a light source receiving window, a first flange, a heat absorber shell, a porous ceramic heat-absorbing core, and a second flange , the second graphite gasket and the second end cap, the heat absorber shell is in the shape of a cylinder, the first flange is affixed to the front end of the heat absorber shell, and the second flange is affixed to the heat absorber shell On the rear end face of the body, the heat absorber shell is composed of three layers of cylinders with different diameters, the three layers of cylinders with different diameters are coaxially arranged, and the outer wall of the outermost cylinder is processed with two air inlets. Two annular chambers are formed between three layers of cylinders with different diameters. The two annular chambers communicate with each other. Three circles of through holes are sequentially processed in the axial direction on the innermost cylinder wall. Each circle The through holes are evenly distributed along the circumferential direction of the innermost cylinder;

The first end cover is in the shape of a ring, the first end cover is installed on the first flange, a first graphite gasket is arranged between the first end cover and the first flange, the light source receiving window is a quartz optical receiving window, and the light source The receiving window is composed of a curved surface and an outer edge. The outer edge of the light source receiving window is installed between the first end cover and the first flange. The porous ceramic heat-absorbing core includes a cylindrical porous ceramic heat-absorbing core, three circles with the same inner diameter Ring-shaped ceramic heat-absorbing core and three annular ceramic heat-absorbing cores whose inner diameters gradually shrink The ring-shaped ceramic heat-absorbing core is sequentially embedded in the heat-absorbing shell along the length direction of the heat-absorbing shell, and the three circles of through holes on the innermost cylindrical wall absorb heat with three ring-shaped ceramics with the same inner diameter. Corresponding setting of the core, three ring-shaped ceramic heat-absorbing cores with inner diameters gradually tapered from the inside to the outside, the three ring-shaped ceramic heat-absorbing cores with the same inner diameter form a heat-absorbing chamber, and the three inner diameters gradually shrink The circular ceramic heat-absorbing core forms a mixing chamber, the second end cover is installed on the second flange, a second graphite gasket is arranged between the second end cover and the second flange, and the secondary collector is a conical cylinder Shape, the small end of the secondary collector is fixed on the first end cover, the conical wall of the secondary collector is provided with a water cooling chamber along the circumferential direction, the lower part of the secondary collector is provided with a water inlet, and the secondary collector The upper part is provided with a water outlet.

Compared with existing solar heat absorbers, the present invention has the following beneficial effects:

The secondary concentrator of the present invention gathers the solar radiation with lower energy flow, increases the effective utilization area of solar energy, and improves the total amount of heat absorbed by the solar air heating device using solar energy; on the other hand, it effectively blocks the high temperature of the present invention. The concentrated energy flow around the inlet of the solar air heating device improves the operation stability and service life;

The mixing chamber is made of porous ceramic material, and the mixing chamber is located outside the heat-absorbing chamber, which can reduce the heat dissipation of the mixing chamber and reuse the heat of the mixing chamber, greatly improving the energy utilization efficiency and reducing the heat loss;

The outside normal temperature gas enters the two annular chambers of the heat absorber shell for preheating, and then enters the heat absorption chamber through the three circles of through holes on the innermost cylinder wall, and the outside normal temperature gas flows along the porous ceramic heat absorbing core. The side wall enters the internal pores of the porous ceramic for convective heat exchange, passes through the porous ceramic and enters the cavities of three circular ceramic heat-absorbing cores with the same inner diameter, and then passes through the cylindrical porous ceramic heat-absorbing core for convective heat exchange, The porous ceramic composite structure of the present invention can ensure that the outside air at normal temperature passes through the porous ceramic and conducts sufficient convective heat exchange with the porous ceramic, thereby ensuring the excellent heat exchange performance of the air heating device of the present invention;

After the ambient temperature gas flows through the two annular chambers of the heat absorber shell, the temperature rises and the heat between the sleeve walls is also taken away to ensure that the temperature of the heat absorber cavity will not be too high. On the one hand The heat dissipation loss of the cavity wall of the heat absorber is reduced, and on the other hand, the service life of the heat absorber is improved, so that the shell of the heat absorber will not be deformed due to excessive temperature.

Description of drawings

Fig. 1 is a schematic cross-sectional view of the overall structure of the high-temperature solar air heating device of the present invention.

detailed description

Embodiment 1: As shown in Figure 1, the high-temperature solar air heating device of this embodiment includes a secondary concentrator 1, a first end cover 2, a first graphite gasket 3, a light source receiving window 4, and a first flange 5 , heat absorber shell 6, porous ceramic heat absorbing core 7, second flange 8, second graphite gasket 9 and second end cap 10, heat absorber shell 6 is cylindrical shape, first flange 5 It is fixed on the front end surface of the heat absorber shell 6, and the second flange 8 is fixed on the rear end surface of the heat absorber shell 6. The heat absorber shell 6 is composed of three layers of cylinders with different diameters. Three layers of cylinders with different diameters are coaxially arranged, and two air inlet holes are processed on the outer wall of the outermost cylinder, and two annular chambers are formed between the three layers of cylinders with different diameters. The two annular chambers are connected to each other, and three circles of through holes are sequentially processed in the axial direction on the innermost cylinder wall, and each circle of through holes is evenly distributed along the circumferential direction of the innermost cylinder;

The first end cover 2 is in the shape of a ring, the first end cover 2 is installed on the first flange 5, a first graphite gasket 3 is arranged between the first end cover 2 and the first flange 5, and a light source receiving window 4 It is a quartz optical receiving window. The light source receiving window 4 is composed of a curved surface and an outer edge. The outer edge of the light source receiving window 4 is installed between the first end cover 2 and the first flange 5. The porous ceramic heat-absorbing core 7 includes a cylindrical Porous ceramic heat-absorbing core, three annular ceramic heat-absorbing cores with the same inner diameter and three annular ceramic heat-absorbing cores with successively tapered inner diameters, three annular ceramic heat-absorbing cores with the same inner diameter, cylindrical porous The ceramic heat-absorbing core and three ring-shaped ceramic heat-absorbing cores with successively tapered inner diameters are sequentially embedded in the heat-absorbing shell 6 along the length direction of the heat-absorbing shell 6, and the three on the innermost cylindrical wall The ring through hole is set corresponding to the three ring-shaped ceramic heat-absorbing cores with the same inner diameter. The ceramic heat-absorbing core forms a heat-absorbing chamber, and three ring-shaped ceramic heat-absorbing cores whose inner diameters gradually shrink form a mixing chamber. The second end cover 10 is installed on the second flange 8. The second end cover 10 is connected with the second method A second graphite gasket 9 is arranged between the flanges 8, the secondary collector 1 is in the shape of a conical cylinder, the small end of the secondary collector 1 is fixed on the first end cover 2, and the conical cylinder wall of the secondary collector 1 A water cooling chamber is provided along the circumferential direction inside, a water inlet is provided at the lower part of the secondary collector 1 , and a water outlet is provided at the upper part of the secondary collector 1 .

Embodiment 2: As shown in FIG. 1 , the curved surface of the light source receiving window 4 in this embodiment is a curved surface for solar energy flow distribution. Such a design can increase the transmittance of solar radiation energy, thereby further increasing the total amount of heat absorbed by the solar air heating device using solar energy. Other components and connections are the same as those in the first embodiment.

Embodiment 3: In this embodiment, the number of through holes per circle on the innermost cylinder wall is eight. Such a design can ensure a sufficient heat exchange area between the gas and the porous ceramic and improve the heat exchange performance of the cavity. Other compositions and connections are the same as those in Embodiment 1 or Embodiment 2.

Embodiment 4: In this embodiment, the first flange 5 is integrally welded with the front end surface of the heat absorber shell 6 , and the second flange 8 is integrally welded with the rear end surface of the heat absorber shell 6 . Such a design can make the front and rear end faces of the heat absorber shell 6 and the front and rear end covers disassemble and assemble conveniently and quickly, and it is easy to maintain and clean the light source receiving window 4 and replace the internal heat absorbing core. Other components and connections are the same as those in the third embodiment.

Embodiment 5: As shown in FIG. 1 , in this embodiment, the second end cover 10 is installed on the second flange 8 through bolts. So designed, easy to disassemble. Other compositions and connections are the same as those in Embodiment 1, 2 or 4.

Embodiment 6: As shown in FIG. 1 , in this embodiment, the first end cover 2 is installed on the first flange 5 through bolts. So designed, easy to disassemble. Other compositions and connections are the same as those in Embodiment 5.

Embodiment 7: As shown in FIG. 1 , the air heating device in this embodiment further includes a target stage support 11 , and the small end of the secondary concentrator 1 is welded to the first end cover 2 through the target stage support 11 . Such a design can avoid the high-temperature heat conduction effect of the high-temperature first end cap 2 on the secondary concentrator 1 as far as possible, and the secondary concentrator 1 will not be deformed, thereby ensuring the optical performance of the secondary concentrator 1 . Other compositions and connections are the same as those in Embodiment 1, 2, 4 or 6.

working principle:

At the beginning stage, it is necessary to find out the position of the focused light spot, and use the relative position of the reflected light spot on the surface of the secondary concentrator 1 to accurately adjust the primary concentrator, stop when the center of the light spot completely enters the light source receiving window 4, and start the supply of external normal temperature gas; During the working process of the invented high-temperature solar air heating device, outside normal temperature gas enters the two annular chambers of the heat absorber shell for preheating, and then enters the heat-absorbing chamber through the three circles of through holes on the innermost cylinder wall. Chamber, along the side wall of the porous ceramic heat-absorbing core, enters the internal pores of the porous ceramic for convective heat exchange, and then passes through the porous ceramic into the cavity of three circular ceramic heat-absorbing cores with the same inner diameter, and then passes through the cylindrical porous ceramic The ceramic heat-absorbing core performs convective heat exchange, and finally mixes and flows out evenly at the back-end mixing chamber, so as to achieve the purpose of increasing temperature and pressure; when the work is over, first evacuate the light spot while maintaining the ventilation state of the cavity, and then close the gas supply. After the cavity is cooled down, check each experimental component, especially the light source receiving window 4, the secondary concentrator 1, the first end cover 2 and their corresponding sealing conditions.

Claims (7)

1. A high-temperature solar air heating device, comprising a secondary concentrator (1), a first end cover (2), a first graphite gasket (3), a light source receiving window (4), and a first flange (5) , heat absorber housing (6), porous ceramic heat absorbing core (7), second flange (8), second graphite gasket (9) and second end cap (10), said light source receiving window ( 4) is a quartz optical receiving window, the secondary concentrator (1) is conical, the small end of the secondary concentrator (1) is fixed on the first end cover (2), and the secondary concentrator (1) ) is provided with a water-cooling cavity along the circumferential direction in the conical cylinder wall, the lower part of the secondary collector (1) is provided with a water inlet, and the upper part of the secondary collector (1) is provided with a water outlet, it is characterized in that: the heat-absorbing The shell (6) is cylindrical, the first flange (5) is affixed to the front end face of the heat absorber shell (6), and the second flange (8) is affixed to the heat absorber shell ( 6) on the rear end face, the heat absorber shell (6) is composed of three layers of cylinders with different diameters, the three layers of cylinders with different diameters are coaxially arranged, and the outer wall of the outermost cylinder is processed with Two air inlet holes, two annular chambers are formed between three layers of cylinders with different diameters, the two annular chambers communicate with each other, and three circles of through holes are sequentially processed in the axial direction on the innermost cylinder wall. holes, and each circle of through holes is evenly distributed along the circumferential direction of the innermost cylinder; The first end cover (2) is in the shape of a ring, the first end cover (2) is installed on the first flange (5), and the first end cover (2) and the first flange (5) are provided with a second A graphite gasket (3), the light source receiving window (4) is composed of a curved surface and an outer edge, and the outer edge of the light source receiving window (4) is installed between the first end cover (2) and the first flange (5) , the porous ceramic heat-absorbing core (7) comprises a cylindrical porous ceramic heat-absorbing core, three annular ceramic heat-absorbing cores with the same inner diameter and three annular ceramic heat-absorbing cores with successively tapered inner diameters, and the three inner diameters are consistent The annular ceramic heat-absorbing core, the cylindrical porous ceramic heat-absorbing core and the three annular ceramic heat-absorbing cores whose inner diameters are successively tapered are embedded in the heat absorber sequentially along the length direction of the heat absorber shell (6). In the casing (6), the three circles of through holes on the innermost layer of the cylinder wall are set corresponding to the three ring-shaped ceramic heat-absorbing cores with the same inner diameter. The internal diameters are gradually tapered from inside to outside, and three annular ceramic heat-absorbing cores with the same inner diameter form a heat-absorbing chamber, and three annular ceramic heat-absorbing cores with successively tapering inner diameters form a mixing chamber. The second end cover (10) It is installed on the second flange (8), and a second graphite gasket (9) is arranged between the second end cover (10) and the second flange (8). 2. The high temperature solar air heating device according to claim 1, characterized in that: the curved surface of the light source receiving window (4) is a solar energy flow distribution curved surface. 3. The high-temperature solar air heating device according to claim 1 or 2, characterized in that: the number of through holes per circle on the innermost cylinder wall is eight. 4. The high-temperature solar air heating device according to claim 3, characterized in that: the first flange (5) is welded together with the front end of the heat absorber housing (6), and the second flange (8) It is welded into one body with the rear end face of the heat absorber housing (6). 5. The high-temperature solar air heating device according to claim 1, 2 or 4, characterized in that the second end cover (10) is installed on the second flange (8) by bolts. 6. The high temperature solar air heating device according to claim 5, characterized in that: the first end cover (2) is installed on the first flange (5) by bolts. 7. The high-temperature solar air heating device according to claim 1, 2, 4 or 6, characterized in that: the air heating device also includes a target stage support (11), and the small end of the secondary concentrator (1) passes through The target stage support (11) is welded on the first end cover (2).