Arc-shaped heat absorption unit and compact solar thermal absorber

Abstract

The present invention discloses an arc-shaped heat absorption unit and a compact solar thermal absorber. The heat absorption unit includes a header medium inlet, a header medium outlet, an inlet header, an outlet header, a hot side curved wall plate, a non-hot side curved wall plate, and an arc-shaped medium channel. The compact solar thermal absorber includes a heat absorber body, a bracket, a heat absorber total inlet, and a heat absorber total outlet; the heat absorber body is fixedly arranged on the bracket; the heat absorber body is composed of a plurality of heat absorption modules arranged in rows and columns; each heat absorption module is composed of a manifold medium inlet, a manifold medium outlet, an inlet manifold, an outlet manifold, and n heat absorption units connected in parallel. The present invention replaces the original straight channel of the heat absorption unit with a curvature structure, forming a medium channel with an arc-shaped structure. The curvature structure uses centrifugal force to guide the fluid to flow toward the hot side wall plate, thereby enhancing the secondary flow effect of S-CO2, thereby improving the heat exchange performance of the heat absorber.

Description

Technical Field

[0001] The present invention relates to the technical field of solar thermal absorbers, in particular to an arc-shaped structured heat absorption unit and a compact solar thermal absorber. Background Art

[0002] Compact solar thermal receivers, with their thin channels as their basic heat exchange units, offer excellent pressure resistance and are one of the most promising S-CO2 (supercritical CO2) receiver types. However, compared to traditional molten salts, S-CO2's heat transfer performance remains relatively poor. Furthermore, S-CO2's large physical properties can lead to localized heat transfer degradation. Consequently, high-density solar flux conditions can generate localized high temperatures and stress concentrations in the receiver, a major cause of stress failure. Therefore, enhancing S-CO2 heat transfer performance within the channels and improving the efficient absorption of high-density energy flux are effective means of reducing the risk of stress failure. Curvature structures are widely used in heat exchange equipment as an effective means of enhancing heat transfer. The paper "Appl. Therm. Eng, 2024, 240: 122202" describes the application of a serpentine tube with a curvature structure to a tubular receiver. The periodic curvature of the structure induces strong secondary flow within the S-CO2, significantly enhancing S-CO2 heat transfer performance. However, when the heated side appears on the inner side of the curvature, the structure will produce greater structural constraints, thereby generating greater thermal stress.

[0003] In addition, energy flow mismatch in the absorber is another major cause of stress failure in the absorber. The document "SolEnergy, 2021, 223: 72-86." points out that when the heat flux distribution outside the absorber does not match the shape of the working fluid flow distribution inside the absorber, a large temperature gradient will be generated in the absorber, thereby generating significant thermal stress. At the same time, it was found that the energy flow matching characteristics of the tubular absorber can be effectively improved by adjusting the inlet and outlet positions, thereby reducing the risk of stress failure caused by energy flow mismatch. However, energy flow mismatch has not received attention in compact solar absorbers. Improving the energy flow matching characteristics of compact solar absorbers is an important guarantee for the safe operation of compact solar absorbers. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the technical problem to be solved by the present invention is to provide an arc-shaped heat absorption unit and a compact solar heat absorber.

[0005] The present invention solves the technical problem of the heat absorption unit by providing a heat absorption unit with an arc structure, characterized in that the heat absorption unit includes a header medium inlet, a header medium outlet, an inlet header, an outlet header, a hot side curved wall plate, a non-hot side curved wall plate and an arc-shaped medium channel;

[0006] The hot side curvature wall panel and the non-hot side curvature wall panel are both composed of two curved plates with arc-shaped radial cross-sections connected side by side, and the convex surfaces of the two curved plates are located on the same side; the hot side curvature wall panel and the non-hot side curvature wall panel are fixedly connected, and the concave surface of the hot side curvature wall panel matches the convex surface of the non-hot side curvature wall panel; two rows of curved medium channels are arranged between the hot side curvature wall panel and the non-hot side curvature wall panel along the tangential direction, and each row of curved medium channels corresponds to one curved plate; two rows of diversion ports and two rows of confluence ports are provided on the non-hot side curvature wall panel, and each curved plate corresponds to one row of diversion ports and a row of confluence ports; the two rows of confluence ports are adjacent to each other; the two ends of each arc-shaped medium channel are respectively connected with a respective diversion port and a confluence port; an outlet header is fixed on the non-hot side curvature wall plate, located at the two rows of confluence ports and connected with the two rows of confluence ports; two inlet headers are fixed on the non-hot side curvature wall plate, respectively located at a respective row of diversion ports and connected with a respective row of diversion ports; each inlet header is provided with a header medium inlet and connected with the inlet header, and each outlet header is provided with a header medium outlet and connected with the outlet header.

[0007] The present invention solves the technical problem of a compact solar thermal absorber by providing a compact solar thermal absorber, comprising a thermal absorber body, a bracket, a thermal absorber main inlet, and a thermal absorber main outlet; the thermal absorber body is fixedly mounted on the bracket; the thermal absorber body is characterized in that the thermal absorber body comprises a plurality of thermal absorption modules arranged in rows and columns; each thermal absorption module comprises a manifold medium inlet, a manifold medium outlet, an inlet manifold, an outlet manifold, and n thermal absorption units connected in parallel;

[0008] An inlet manifold is fixed to the non-hot side curved wall plate of the n heat absorbing units, is located at the header medium inlet of the n heat absorbing units and is connected to the header medium inlet of the n heat absorbing units; a manifold medium inlet is provided on the inlet manifold; both ends of the manifold medium inlet are connected to the inlet manifold and the main inlet of the heat absorber respectively;

[0009] An outlet manifold is fixed on the non-hot side curvature wall panel of n heat absorbing units, is located at the header medium outlet of n heat absorbing units and is connected with the header medium outlet of n heat absorbing units; a manifold medium outlet is provided on the outlet manifold; the two ends of the manifold medium outlet are respectively connected with the outlet manifold and the total outlet of the heat absorber.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] (1) This invention creatively transforms the core heat absorption unit of a compact solar thermal absorber, replacing the original straight channel with a curved structure formed by sweeping an arc curve, forming a medium channel with an arc structure. This curved structure uses centrifugal force to guide the fluid flow toward the hot side wall plate, enhancing the secondary flow effect of S-CO2, thereby improving the heat exchange performance of the absorber and enhancing the effective absorption of solar energy flow.

[0012] (2) The compact solar thermal absorber of the present invention is based on a modular design and has the characteristics of flexible adjustment. Taking into account the differences in energy flow distribution at different positions of the absorber, the inlet and outlet positions of the heat absorption unit are innovatively adjusted to design different medium inlet and outlet schemes to form three typical flow distributions to adapt to the energy flow distribution characteristics of the absorber and improve the energy flow matching performance of the heat absorption unit. This design not only improves the energy flow matching characteristics of the absorber and reduces temperature gradients, but also reduces the risk of stress failure and can extend the service life of the equipment.

[0013] (3) The present invention enhances the heat transfer performance of the hot side plate and reduces the wall temperature through the curvature structure design, thereby effectively reducing the temperature gradient and thermal stress within the channel. At the same time, the curvature structure reduces the structural constraints of the medium channel, making the stress distribution more uniform, reducing the risk of stress failure in the channel, and further improving the operational safety of the heat absorber.

[0014] (4) The curvature structure of the medium channel design in the present invention makes the transition process of the fluid from the diversion port to the confluence port smoother, effectively reduces the pressure drop of the heat absorber, significantly reduces the pumping power requirement, and improves the overall energy efficiency of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A stereoscopic view of the heat absorption unit of the present invention from a main perspective;

[0016] Figure 2 A rear perspective view of the heat absorption unit of the present invention;

[0017] Figure 3 An exploded view of the heat absorption unit of the present invention from a rear perspective;

[0018] Figure 4 It is a schematic structural diagram of the hot side curvature wall panel of the present invention;

[0019] Figure 5 For the present invention Figure 4 A partial enlarged view of the hot side curvature wall panel;

[0020] Figure 6 A three-dimensional diagram of the arc-shaped medium channel of the present invention;

[0021] Figure 7A rear perspective view of the non-hot side curved wall panel of the present invention;

[0022] Figure 8 It is a rear view of the non-hot side curvature wall panel of the present invention;

[0023] Figure 9 A rear perspective view of a heat absorbing unit with a header medium inlet and a header medium outlet at different arrangement positions of the present invention;

[0024] Figure 10 is a perspective view of a compact solar thermal absorber according to the present invention;

[0025] Figure 11 is a front view of the compact solar thermal absorber of the present invention;

[0026] Figure 12 A front-view stereoscopic view of a heat absorption module with a manifold medium inlet and a manifold medium outlet at different arrangement positions of the present invention;

[0027] Figure 13 The figure is a rear perspective stereogram of a heat absorption module with a manifold medium inlet and a manifold medium outlet arranged at different positions according to the present invention.

[0028] In the figure, the heat absorber body 1, the bracket 2, the heat absorber main inlet 3, the heat absorber main outlet 4, and the heat absorption unit 5;

[0029] Manifold medium inlet 101, manifold medium outlet 102, inlet manifold 103, outlet manifold 104;

[0030] Manifold medium inlet 501 , manifold medium outlet 502 , inlet manifold 503 , outlet manifold 504 , hot side curved wall plate 505 , non-hot side curved wall plate 506 , arc-shaped medium channel 507 , diversion port 508 , and confluence port 509 . DETAILED DESCRIPTION

[0031] The specific embodiments of the present invention are given below. The specific embodiments are only used to further illustrate the present invention and do not limit the scope of protection of the present invention.

[0032] The present invention provides a heat absorbing unit with an arc structure (abbreviated as heat absorbing unit), characterized in that the heat absorbing unit 5 includes a header medium inlet 501, a header medium outlet 502, an inlet header 503, an outlet header 504, a hot side curved wall plate 505, a non-hot side curved wall plate 506 and a curved medium channel 507;

[0033] The hot side curvature wall panel 505 and the non-hot side curvature wall panel 506 are both composed of two curved plates with arc-shaped radial cross-sections (i.e., horizontal cross-sections) connected side by side, and the convex surfaces of the two curved plates are located on the same side; the hot side curvature wall panel 505 and the non-hot side curvature wall panel 506 are fixedly connected, and the concave surface of the hot side curvature wall panel 505 cooperates with the convex surface of the non-hot side curvature wall panel 506; two rows of curved medium channels 507 are arranged along the tangential direction between the hot side curvature wall panel 505 and the non-hot side curvature wall panel 506, and each row of curved medium channels 507 corresponds to one curved plate; two rows of diversion ports 508 and two rows of confluence ports 509 are opened on the non-hot side curvature wall panel 506, and each curved plate corresponds to one row of diversion ports 508 and one row of confluence ports 509. There are two rows of confluence ports 509; two rows of confluence ports 509 are adjacent to each other; the two ends of each arc-shaped medium channel 507 are respectively connected with a respective diversion port 508 and a confluence port 509; an outlet manifold 504 is fixed on the non-hot side curvature wall plate 506, located at the two rows of confluence ports 509 and connected with the two rows of confluence ports 509; two inlet manifolds 503 are fixed on the non-hot side curvature wall plate 506, located at a respective row of diversion ports 508 and connected with a respective row of diversion ports 508; each inlet manifold 503 is provided with a manifold medium inlet 501 and is connected with the inlet manifold 503, and each outlet manifold 504 is provided with a manifold medium outlet 502 and is connected with the outlet manifold 504.

[0034] Preferably, the arc is a circular arc or an elliptical arc, more preferably a semicircle or a semiellipse.

[0035] Preferably, the two rows of arc-shaped medium channels 507 are completely identical.

[0036] Preferably, in each column of arc-shaped medium channels 507 , a plurality of arc-shaped medium channels 507 are evenly arranged along the axial direction (ie, the vertical direction).

[0037] Preferably, the concave surface of the hot side curvature wall plate 505 is provided with two rows of identical through grooves along the tangential direction, and each row of through grooves corresponds to an arc-shaped plate; in each row of through grooves, several through grooves are evenly arranged along the axial direction; the hot side curvature wall plate 505 and the non-hot side curvature wall plate 506 cooperate with each other to form an arc-shaped medium channel 507.

[0038] Preferably, the normal cross-section of the arc-shaped medium channel 507 is semicircular or semi-elliptical.

[0039] Preferably, along the axial direction, the arrangement positions of the manifold medium inlet 501 and the manifold medium outlet 502 include three situations: the manifold medium inlet 501 is located above the manifold medium outlet 502, the manifold medium inlet 501 and the manifold medium outlet 502 are located on the same horizontal plane (that is, at the same height), and the manifold medium inlet 501 is located below the manifold medium outlet 502.

[0040] Preferably, in the arrangement position where the header medium inlet 501 is located above the header medium outlet 502, the header medium inlet 501 is located at the upper end of the inlet header 503, and the header medium outlet 502 is located at the lower end of the outlet header 504 (e.g., Figure 9 (a)); in the arrangement position where the header medium inlet 501 and the header medium outlet 502 are located on the same horizontal plane, the header medium inlet 501 is located in the middle of the inlet header 503, and the header medium outlet 502 is located in the middle of the outlet header 504 (as shown in FIG. Figure 9 (b)); in the arrangement position where the header medium inlet 501 is located below the header medium outlet 502, the header medium inlet 501 is located at the lower end of the inlet header 503, and the header medium outlet 502 is located at the upper end of the outlet header 504 (as shown in FIG. Figure 9 (c)).

[0041] Preferably, when the manifold medium inlet 501 and the manifold medium outlet 502 are located in the same horizontal plane, the manifold medium inlet 501 and the manifold medium outlet 502 are offset tube structures (i.e., one end of the three offset tube structures connected to the inlet manifold 503 and the outlet manifold 504 are located in the same horizontal plane, the other ends of the offset tube structures of the two manifold medium inlets 501 are located in the same horizontal plane, and the other end of the offset tube structure of one manifold medium outlet 502 is not located in the same horizontal plane as the other ends of the offset tube structures of the two manifold medium inlets 501); in the other two arrangement positions (i.e., the manifold medium inlet 501 is located above the manifold medium outlet 502, and the manifold medium inlet 501 is located below the manifold medium outlet 502), the manifold medium inlet 501 and the manifold medium outlet 502 are straight tube structures.

[0042] The present invention also provides a compact solar thermal absorber (abbreviated as absorber), comprising a heat absorber body 1, a bracket 2, a heat absorber main inlet 3, and a heat absorber main outlet 4; the heat absorber body 1 is fixedly mounted on the bracket 2; the heat absorber body 1 is characterized in that it comprises a plurality of heat absorbing modules arranged in rows and columns; each heat absorbing module comprises a manifold medium inlet 101, a manifold medium outlet 102, an inlet manifold 103, an outlet manifold 104, and n (preferably 3 to 5, more preferably 3) heat absorbing units 5 connected in parallel; the heat absorbing modules are connected in parallel and then connected in series with the heat absorber main inlet 3 and the heat absorber main outlet 4;

[0043] An inlet manifold 103 is fixed to the non-hot-side curved wall plate 506 of the n heat absorbing units 5, located at the header medium inlet 501 of the n heat absorbing units 5 and connected to the header medium inlet 501 of the n heat absorbing units 5; a manifold medium inlet 101 is provided on the inlet manifold 103; the two ends of the manifold medium inlet 101 are respectively connected to the inlet manifold 103 and the heat absorber main inlet 3;

[0044] An outlet manifold 104 is fixed on the non-hot side curved wall plate 506 of the n heat absorbing units 5, is located at the manifold medium outlet 502 of the n heat absorbing units 5 and is connected to the manifold medium outlet 502 of the n heat absorbing units 5; a manifold medium outlet 102 is provided on the outlet manifold 104; the two ends of the manifold medium outlet 102 are respectively connected to the outlet manifold 104 and the total outlet 4 of the heat absorber.

[0045] Preferably, the heat absorber body 1 is cylindrical.

[0046] The working principle of the compact solar thermal absorber is as follows: low-temperature medium enters the absorber through the absorber main inlet 3; the low-temperature medium entering the absorber is divided and enters the absorber module; the low-temperature medium in the absorber module enters the absorber module through the manifold medium inlet 101; the low-temperature medium is distributed to each absorber unit 5 through the inlet manifold 103; the low-temperature medium enters the absorber unit 5 through the manifold medium inlet 501; the low-temperature medium in the absorber unit 5 enters the arc-shaped medium channel 507 through the inlet manifold 503; the low-temperature medium is heated by the solar flux from the mirror field radiation in the arc-shaped medium channel 507 to form a high-temperature medium; the high-temperature medium enters the outlet manifold 504; the high-temperature medium is collected at the manifold medium outlet 502 through the outlet manifold 504 and leaves the absorber unit 5; the high-temperature medium leaving the absorber unit 5 enters the outlet manifold 104; the outlet manifold 104 merges the high-temperature medium to the manifold medium outlet 102; then, the high-temperature medium in the absorber module flows to the absorber main outlet 4 and leaves the absorber.

[0047] Any matters not described in the present invention are applicable to the prior art.

Claims

1. An arc-shaped heat absorption unit, characterized in that: The heat absorption unit (5) comprises a header medium inlet (501), a header medium outlet (502), an inlet header (503), an outlet header (504), a hot side curvature wall plate (505), a non-hot side curvature wall plate (506), and an arc-shaped medium channel (507); The hot side curvature wall plate (505) and the non-hot side curvature wall plate (506) are both composed of two curved plates with arc-shaped radial cross-sections connected side by side, and the convex surfaces of the two curved plates are located on the same side; the hot side curvature wall plate (505) and the non-hot side curvature wall plate (506) are fixedly connected, and the concave surface of the hot side curvature wall plate (505) matches the convex surface of the non-hot side curvature wall plate (506); two rows of curved medium channels (507) are provided between the hot side curvature wall plate (505) and the non-hot side curvature wall plate (506) along the tangential direction, and each row of curved medium channels (507) corresponds to one curved plate; two rows of diversion ports (508) and two rows of confluence ports (509) are provided on the non-hot side curvature wall plate (506), and each curved plate corresponds to one row of diversion ports (508) and one row of confluence ports (509); the two rows of diversion ports (508) and the non-hot side curvature wall plate (506) are fixedly connected, and the concave surface of the hot side curvature wall plate (505) matches the convex surface of the non-hot side curvature wall plate (506); two rows of curved medium channels (507) are provided between the hot side curvature wall plate (505) and the non-hot side curvature wall plate (506) along the tangential direction, and each row of curved medium channels (507) corresponds to one curved plate; two rows of diversion ports (508) and two rows of confluence ports (509) are provided on the non-hot side curvature wall plate (506), and each row of diversion ports (508) and one row of confluence ports (509) correspond to one curved plate; two rows of diversion ports (508) The two rows of confluence ports (509) are adjacent to each other; both ends of each arc-shaped medium channel (507) are respectively communicated with a respective diversion port (508) and a confluence port (509); an outlet manifold (504) is fixed on the non-hot side curvature wall plate (506), located at the two rows of confluence ports (509) and communicated with the two rows of confluence ports (509); two inlet manifolds (503) are fixed on the non-hot side curvature wall plate (506), located at a respective row of diversion ports (508) and communicated with a respective row of diversion ports (508); each inlet manifold (503) is provided with a manifold medium inlet (501) and communicated with the inlet manifold (503), and each outlet manifold (504) is provided with a manifold medium outlet (502) and communicated with the outlet manifold (504).

2. The arc-shaped heat absorption unit according to claim 1, characterized in that: The two rows of arc-shaped medium channels (507) are exactly the same.

3. The arc-shaped heat absorption unit according to claim 1 or 2, characterized in that: In each row of arc-shaped medium channels (507), a plurality of arc-shaped medium channels (507) are evenly arranged along the axial direction.

4. The arc-shaped heat absorption unit according to claim 1, characterized in that: The concave surface of the hot side curvature wall plate (505) is provided with two rows of identical through grooves along the tangential direction, and each row of through grooves corresponds to an arc-shaped plate; in each row of through grooves, a plurality of through grooves are evenly arranged along the axial direction; the hot side curvature wall plate (505) and the non-hot side curvature wall plate (506) cooperate with each other to form an arc-shaped medium channel (507).

5. The arc-shaped heat absorption unit according to claim 1, characterized in that: The normal cross-section of the arc-shaped medium channel (507) is in the shape of a semicircle or a semi-ellipse.

6. The arc-shaped heat absorption unit according to claim 1, characterized in that: The arrangement positions of the manifold medium inlet (501) and the manifold medium outlet (502) include: the manifold medium inlet (501) is located above the manifold medium outlet (502), the manifold medium inlet (501) and the manifold medium outlet (502) are located on the same horizontal plane, and the manifold medium inlet (501) is located below the manifold medium outlet (502).

7. The arc-shaped heat absorption unit according to claim 6, characterized in that: When the header medium inlet (501) and the header medium outlet (502) are located on the same horizontal plane, the header medium inlet (501) and the header medium outlet (502) are offset pipe structures; in the other two arrangement positions, the header medium inlet (501) and the header medium outlet (502) are straight pipe structures.

8. The arc-shaped heat absorption unit according to claim 6, characterized in that: In an arrangement position where the manifold medium inlet (501) is located above the manifold medium outlet (502), the manifold medium inlet (501) is located at the upper end of the inlet manifold (503), and the manifold medium outlet (502) is located at the lower end of the outlet manifold (504); in an arrangement position where the manifold medium inlet (501) and the manifold medium outlet (502) are located on the same horizontal plane, the manifold medium inlet (501) is located in the middle of the inlet manifold (503), and the manifold medium outlet (502) is located in the middle of the outlet manifold (504); in an arrangement position where the manifold medium inlet (501) is located below the manifold medium outlet (502), the manifold medium inlet (501) is located at the lower end of the inlet manifold (503), and the manifold medium outlet (502) is located at the upper end of the outlet manifold (504).

9. A compact solar heat absorber, comprising a heat absorber body (1), a bracket (2), a heat absorber main inlet (3) and a heat absorber main outlet (4); the heat absorber body (1) is fixedly arranged on the bracket (2); and is characterized in that: The heat absorber body (1) is composed of a plurality of heat absorption modules arranged in rows and columns; each heat absorption module is composed of a manifold medium inlet (101), a manifold medium outlet (102), an inlet manifold (103), an outlet manifold (104) and n heat absorption units (5) according to any one of claims 1 to 8 connected in parallel; An inlet manifold (103) is fixed on the non-hot side curvature wall plate (506) of the n heat absorbing units (5), is located at the header medium inlet (501) of the n heat absorbing units (5) and is connected to the header medium inlet (501) of the n heat absorbing units (5); a manifold medium inlet (101) is provided on the inlet manifold (103); both ends of the manifold medium inlet (101) are respectively connected to the inlet manifold (103) and the heat absorber main inlet (3); An outlet manifold (104) is fixed on the non-hot side curvature wall plate (506) of the n heat absorbing units (5), is located at the header medium outlet (502) of the n heat absorbing units (5) and is connected to the header medium outlet (502) of the n heat absorbing units (5); a manifold medium outlet (102) is provided on the outlet manifold (104); both ends of the manifold medium outlet (102) are respectively connected to the outlet manifold (104) and the total outlet (4) of the heat absorber.

10. The compact solar thermal absorber according to claim 9, characterized in that The heat absorber body (1) is cylindrical.

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