Photovoltaic photo-thermal air type heat collector based on W-shaped discontinuous baffle combined fins

Abstract

The invention relates to the field of air type heat collectors, in particular to a photovoltaic photo-thermal air type heat collector based on W-shaped discontinuous baffle combined fins, a light-transmitting plate is fixedly mounted at the top of a shell, a base plate is attached to the bottom of the light-transmitting plate, and a photovoltaic cell is arranged between the light-transmitting plate and the base plate; an air flow channel is arranged between the base plate and the bottom of the shell, a fin structure is arranged in the air flow channel and comprises a W-shaped discontinuous baffle attached to the bottom of the base plate, the W-shaped discontinuous baffle comprises a plurality of sets of V-shaped baffles sequentially connected in the width direction of the air flow channel, and openings of the V-shaped baffles face the inlet side of the air flow channel. The two arms of the V-shaped baffle are respectively provided with a plurality of flow passing gaps which are evenly arranged at intervals, a flow boundary layer on the back face of the base plate is thinned, the W-shaped discontinuous baffle generates stable secondary flow, under the action of the Coanda auxiliary ribs, the strength of vortexes is strengthened, mixing of cold fluid and hot fluid is promoted, meanwhile, air on the upper side and the lower side of an air flow channel is mixed, and therefore the heat exchange efficiency is improved. The air utilization rate is improved.

Description

Technical Field

[0001] This invention relates to the field of air-type solar collectors, and more specifically to a photovoltaic-thermal air-type solar collector based on a W-shaped discontinuous baffle combined with fins. Background Technology

[0002] Air-type solar photovoltaic (PV) thermal collectors are devices that convert some of the received solar radiation into electrical energy and most into heat energy. However, due to the physical properties of air and the formation of a flow boundary layer, the output efficiency of PV thermal systems is relatively low.

[0003] In the prior art, by setting W-shaped baffle fins in the air flow channel, the secondary flow generated by them has a significant effect on improving heat transfer performance; however, there are problems such as local high temperature and uneven vortex distribution. Furthermore, the W-shaped baffle fins mainly play the role of thinning the flow boundary layer, while having little disturbance to the air in the free flow region, thus resulting in an unsatisfactory heat collection effect of the collector. Summary of the Invention

[0004] The purpose of this invention is to provide a photovoltaic-thermal air collector based on W-shaped discontinuous baffle combined fins, which improves heat exchange efficiency by optimizing the fin structure, thereby solving the defects mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A photovoltaic-thermal air-type solar collector based on a W-shaped discontinuous baffle combined with fins includes a housing. A light-transmitting plate is fixedly installed on the top of the housing, and a substrate is attached to the bottom of the light-transmitting plate. A photovoltaic cell is disposed between the light-transmitting plate and the substrate. An air flow channel is provided between the substrate and the bottom of the housing. A fin structure is provided in the air flow channel. The fin structure includes a W-shaped discontinuous baffle attached to the bottom of the substrate. The W-shaped discontinuous baffle includes a plurality of V-shaped baffles connected sequentially along the width direction of the air flow channel. The opening of the V-shaped baffle faces the inlet side of the air flow channel, and a plurality of flow gaps are provided evenly spaced on the two arms of the V-shaped baffle.

[0006] As a further improvement, the angles between the windward and leeward sides of the W-shaped discontinuous baffle and the substrate are both obtuse angles.

[0007] As a further improvement, the rib structure also includes a Coanda auxiliary rib suspended below the W-shaped discontinuous baffle. The Coanda auxiliary rib includes V-shaped ribs that correspond one-to-one with the V-shaped baffles. The openings of the V-shaped ribs face the outlet side of the airflow channel. A triangular wing plate is fixedly installed on the top of the V-shaped rib. The triangular wing plate is an isosceles triangle, and the apex of the triangular wing plate is located directly below the tip of the corresponding V-shaped baffle. The apex of the triangular wing plate is inclined towards the outlet side of the airflow channel.

[0008] As a further improvement, triangular flaps are fixedly installed on both sides of the triangular wing plate along the width direction of the airflow channel. One side line of the flap plate coincides with one waist of the triangular wing plate, and the other side line coincides with the top leading edge of the corresponding side of the V-shaped rib plate.

[0009] As a further improvement, the rib structure also includes a W-shaped linear auxiliary protrusion located below the Coanda auxiliary rib. The W-shaped linear auxiliary protrusion is attached to the inner side of the bottom wall of the airflow channel. A gradient channel is provided between the Coanda auxiliary rib and the W-shaped linear auxiliary protrusion. The cross-section of the gradient channel in the vertical direction gradually contracts and then expands along the airflow direction.

[0010] As a further improvement, the projection of the W-shaped linear auxiliary protrusion along the vertical direction coincides with the Coanda auxiliary rib.

[0011] As a further improvement, the top of the Coanda auxiliary rib is horizontally positioned, and the bottom of the Coanda auxiliary rib is provided with a windward panel that gradually slopes downward along the airflow direction. The lower end of the windward panel is connected to a deflection curved panel that deflects upward in an arc along the airflow direction.

[0012] Compared with the prior art, the beneficial effects of the present invention are: The rib structure of this invention reduces the flow boundary layer on the back of the substrate, generates a stable secondary flow through the W-shaped discontinuous baffle, and strengthens the vortex intensity under the action of the Coanda auxiliary rib, promoting the mixing of hot and cold fluids. At the same time, the air on the upper and lower sides of the air channel is mixed, improving the air utilization rate, significantly enhancing the heat transfer effect, improving the heat collection efficiency of the solar collector, and synergistically improving the photoelectric conversion efficiency. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention; Figure 2 yes Figure 1 An explosion diagram; Figure 3 yes Figure 2 Another structural diagram from a different perspective; Figure 4 This is a schematic diagram of the structure of the W-shaped discontinuous baffle according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of the V-shaped rib plate according to an embodiment of the present invention; Figure 6 yes Figure 1 Schematic diagram of sectional view AA.

[0015] In the diagram: 1-Shell; 2-Shell bottom plate; 3-Side plate; 4-Light-transmitting plate; 5-Substrate; 6-Photovoltaic cell; 7-Airflow channel; 8-W-shaped discontinuous baffle; 9-Coanda auxiliary rib; 10-W-shaped linear auxiliary protrusion; 11-V-shaped baffle; 12-Flow gap; 13-V-shaped rib plate; 14-Triangular wing plate; 15-Flap wing plate; 16-Windward panel; 17-Deflecting curved panel; 18-Gradual channel. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0017] like Figures 1 to 6 As shown, a photovoltaic-thermal air collector based on a W-shaped discontinuous baffle combined with fins includes a housing 1. The housing 1 includes a base plate 2 and upwardly extending side plates 3 fixedly installed on the left and right sides of the base plate 2. A light-transmitting plate 4, which is made of PET board, is fixedly installed between the upper ends of the two side plates 3. A substrate 5 is attached to the bottom of the light-transmitting plate 4. A plurality of photovoltaic cells 6 are arranged in an array between the light-transmitting plate 4 and the substrate 5. The photovoltaic cells 6 are bonded to the bottom of the light-transmitting plate 4 with EVA adhesive.

[0018] The substrate 5 has a three-layer structure. The middle layer of the substrate 5 is an absorption film, which is a selective absorption film made of reduced graphene oxide. The absorption film has a solar absorption rate of 0.92 and a thermal emissivity of 4%. The bottom layer of the substrate 5 is a metal layer with high thermal conductivity. The top layer of the substrate 5 is a textured tempered glass plate, which is bonded to the light-transmitting plate 4 with EVA adhesive.

[0019] An airflow channel 7 is provided between the substrate 5 and the bottom plate 2 of the housing, with the front end of the airflow channel 7 being the inlet side and the rear end being the outlet side. The airflow channel 7 is provided with a rib structure, which is made of metal with high thermal conductivity. Multiple sets of rib structures are evenly spaced along the length of the airflow channel 7. Each set of rib structures includes a W-shaped discontinuous baffle 8, a Coanda auxiliary rib 9, and a W-shaped linear auxiliary protrusion 10.

[0020] like Figure 3 and Figure 4 As shown, a W-shaped discontinuous baffle 8 is attached to the bottom of the substrate 5. The W-shaped discontinuous baffle 8 includes several sets of V-shaped baffles 11 connected sequentially along the width direction of the airflow channel 7. In this embodiment, two sets of V-shaped baffles 11 are arranged side by side, and the two sets of V-shaped baffles 11 are combined to form a W shape. The opening of the V-shape where the V-shaped baffles 11 are located faces forward toward the inlet side of the airflow channel 7. Several flow gaps 12 are provided on the two arms of the V-shaped baffles 11 at uniform intervals. The flow gaps 12 extend from the bottom of the V-shaped baffles 11 to the bottom of the substrate 5, and the flow gaps 12 vertically penetrate the corresponding side arms of the V-shaped baffles 11.

[0021] In this embodiment, the bottom of the W-shaped discontinuous baffle 8 is horizontally arranged, such as... Figure 6 As shown, the angles between the windward and leeward sides of the W-shaped discontinuous baffle 8 and the substrate 5 are both obtuse angles, thereby reducing the resistance to airflow.

[0022] like Figure 2 and Figure 5 As shown, the Coanda auxiliary rib 9 is suspended below the W-shaped discontinuous baffle 8. The Coanda auxiliary rib 9 includes V-shaped ribs 13 that correspond one-to-one with the V-shaped baffles. The opening of the V-shape where the V-shaped ribs 13 are located faces backward toward the outlet side of the airflow channel 7. The adjacent ends of the two V-shaped ribs 13 are fixedly connected together, and the ends of the two V-shaped ribs 13 that are far apart from each other are fixedly connected to the side plate 3. A triangular wing plate 14 is welded to the middle of the top of the V-shaped ribs 13. The triangular wing plate 14 is an isosceles triangle, and the apex of the triangular wing plate 14 is located directly below the tip of the corresponding V-shaped baffle 11. The apex of the triangular wing plate 14 is inclined backward toward the outlet side of the airflow channel 7, thereby reducing the resistance to airflow.

[0023] In addition, triangular flaps 15 are welded to the left and right sides of the delta wing plate 14 along the width direction of the airflow channel 7. One side line of the flap 15 coincides with one waist of the delta wing plate 14, and the other side line coincides with the top leading edge of the corresponding side of the V-shaped rib plate 13.

[0024] like Figure 2 and Figure 6 As shown, the W-shaped linear auxiliary protrusion 10 is located below the Coanda auxiliary rib 9. The W-shaped linear auxiliary protrusion 10 is attached to the top of the housing bottom plate 2, and the projection of the W-shaped linear auxiliary protrusion 10 in the vertical direction coincides with the Coanda auxiliary rib 9. A gradient channel 18 is provided between the Coanda auxiliary rib 9 and the W-shaped linear auxiliary protrusion 10. The cross-section of the gradient channel 18 in the vertical direction first gradually contracts and then expands along the airflow direction.

[0025] In this embodiment, the top of the Coanda auxiliary rib 9 is horizontally positioned, and the bottom of the Coanda auxiliary rib 9 is provided with a windward panel 16 that gradually slopes downward from front to back along the airflow direction. The rear end of the windward panel 16 is connected to a deflection curved panel 17 that curves backward and upward along the airflow direction. The W-shaped linear auxiliary protrusion 10 is provided with a windward surface that gradually rises from front to back and a leeward surface that gradually decreases from front to back. The intersection of the windward and leeward surfaces of the W-shaped linear auxiliary protrusion 10 is the highest point of the W-shaped linear auxiliary protrusion 10, and the highest point of the W-shaped linear auxiliary protrusion 10 corresponds to the lowest point of the Coanda auxiliary rib 9.

[0026] The working principle of this application is as follows: During use, some sunlight shines on the photovoltaic cell 6, which generates electricity; some sunlight passes through the light-transmitting plate 4 and shines on the absorption film in the middle layer of the substrate 5. Due to the low reflectivity of the absorption film to the environment and the high absorptivity of the solar spectrum, this part of the sunlight is efficiently converted into heat energy. Furthermore, the absorption film has extremely low radiative heat transfer to the environment. The heat absorbed by the absorption film heats the substrate 5. This heat energy is attached to the W-shaped discontinuous baffle 8 at the bottom of the substrate 5 and absorbed by the flowing air, which greatly reduces the temperature of the photovoltaic cell 6 and improves the photoelectric conversion efficiency.

[0027] When air enters the airflow channel 7, it is divided into upper and lower sections by the suspended Coanda auxiliary ribs 9: When the upper part of the air passes through the W-shaped discontinuous baffle 8, on the one hand, the air flows laterally along the windward side of the W-shaped discontinuous baffle 8, and forms a transverse angular vortex at the angle between the base plate 5 and the windward side of the W-shaped discontinuous baffle 8. The developing angular vortex is interrupted at the flow gap 12 and passes through the flow gap 12 with the mainstream, and then forms a gap-derived vortex on the rear side of the W-shaped discontinuous baffle 8; on the other hand, the air sinks to its bottom end along the windward side of the W-shaped discontinuous baffle 8. This part of the air forms a free shear flow at the bottom end of the W-shaped discontinuous baffle 8 due to the sudden break of the windward side, and then develops into an irregular high-speed vortex; secondly, under the action of a single V-shaped baffle 11, the air on both sides Air converges and settles towards the center, forming a gradually dissipating longitudinal vortex below the tip of the V-shaped baffle 11. This vortex carries heat from the substrate 5 and the W-shaped discontinuous baffle 8 to the free flow region. When air flows past the delta wing 14 on the upper side of the Coanda auxiliary rib 9, a tip vortex is induced by the tip of the delta wing 14, merging with the longitudinal vortex below the tip of the W-shaped discontinuous baffle 8. This increases the vortex intensity, delays vortex dissipation, and promotes the mixing of hot and cold fluids in the free flow region. Furthermore, the air converging and settling towards the center under the action of a single V-shaped baffle 11 flows to both sides under the guiding action of the flap wing 15, thus forming a circulation within the airflow channel 7 and enhancing heat transfer.

[0028] The air in the lower part, under the action of the gradually narrowing space formed by the windward panel 16 of the Coanda auxiliary rib 9 and the windward surface of the W-shaped linear auxiliary protrusion 10, has increased speed and decreased pressure. When the air flows to the narrowest position of the gradual channel 18, the deflection curved panel 17 of the Coanda auxiliary rib 9 applies a deflection force to the air, thus generating the Coanda effect. This causes the lower part of the air to deflect and flow upward, thereby mixing with the hot air in the upper space of the Coanda auxiliary rib 9, greatly improving the air utilization rate inside the entire airflow channel 7 and improving the output performance of the entire system.

[0029] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A photovoltaic-thermal air collector based on W-shaped discontinuous baffle combined fins, characterized in that... The device includes a housing (1), a light-transmitting plate (4) fixedly installed on the top of the housing (1), a substrate (5) attached to the bottom of the light-transmitting plate (4), and a photovoltaic cell (6) between the light-transmitting plate (4) and the substrate (5); an air flow channel (7) is provided between the substrate (5) and the bottom of the housing (1), and a rib structure is provided in the air flow channel (7). The rib structure includes a W-shaped discontinuous baffle (8) attached to the bottom of the substrate (5). The W-shaped discontinuous baffle (8) includes several sets of V-shaped baffles (11) connected sequentially along the width direction of the air flow channel (7). The opening of the V-shaped baffle (11) faces the inlet side of the air flow channel (7), and several flow gaps (12) are provided evenly spaced on the two arms of the V-shaped baffle (11).

2. A photovoltaic-thermal air collector based on W-shaped discontinuous baffle combined fins as described in claim 1, characterized in that... The angles between the windward and leeward sides of the W-shaped discontinuous baffle (8) and the substrate (5) are both obtuse angles.

3. A photovoltaic-thermal air collector based on W-shaped discontinuous baffle combined fins as described in claim 1, characterized in that... The rib structure also includes a Coanda auxiliary rib (9) suspended below the W-shaped discontinuous baffle (8). The Coanda auxiliary rib (9) includes a V-shaped rib (13) corresponding to the V-shaped baffle (11). The opening of the V-shaped rib (13) faces the outlet side of the airflow channel (7). A triangular wing plate (14) is fixedly installed on the top of the V-shaped rib (13). The triangular wing plate (14) is an isosceles triangle. The apex of the triangular wing plate (14) is located directly below the tip of the corresponding V-shaped baffle (11). The apex of the triangular wing plate (14) is inclined towards the outlet side of the airflow channel (7).

4. A photovoltaic-thermal air collector based on W-shaped discontinuous baffle combined fins as described in claim 3, characterized in that... The triangular wing plate (14) has triangular flaps (15) fixedly installed on both sides along the width direction of the airflow channel (7). One side of the flap (15) coincides with one waist of the triangular wing plate (14), and the other side coincides with the top leading edge of the corresponding side of the V-shaped rib (13).

5. A photovoltaic-thermal air collector based on W-shaped discontinuous baffle combined fins as described in claim 3, characterized in that... The rib structure also includes a W-shaped linear auxiliary protrusion (10) located below the Coanda auxiliary rib (9). The W-shaped linear auxiliary protrusion (10) is attached to the inner side of the bottom wall of the airflow channel (7). A gradient channel (18) is provided between the Coanda auxiliary rib (9) and the W-shaped linear auxiliary protrusion (10). The gradient channel (18) gradually contracts and then expands in the vertical direction along the airflow direction.

6. A photovoltaic-thermal air collector based on W-shaped discontinuous baffle combined fins as described in claim 5, characterized in that... The projection of the W-shaped linear auxiliary protrusion (10) along the vertical direction coincides with the Coanda auxiliary rib (9).

7. A photovoltaic-thermal air collector based on W-shaped discontinuous baffle combined fins as described in claim 5, characterized in that... The top of the Coanda auxiliary rib (9) is horizontally arranged, and the bottom of the Coanda auxiliary rib (9) is provided with a windward panel (16) that gradually slopes downward along the airflow direction. The lower end of the windward panel (16) is connected to a deflection curved panel (17) that deflects upward in an arc along the airflow direction.

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