Explosion-proof lamp with active and passive heat dissipation modes

Abstract

The invention relates to an explosion-proof lamp with active and passive heat dissipation modes, which comprises a heat dissipation shell, a radiation refrigeration coating is arranged outside the heat dissipation shell, the radiation refrigeration coating comprises a substrate layer, a photonic crystal layer and a polymer layer which are sequentially stacked, and the radiation refrigeration coating radiates energy of the heat dissipation shell to the outside of the heat dissipation shell and reflects solar energy; the refrigeration module is arranged in the heat dissipation shell, and the refrigeration module is used for refrigeration so as to reduce the temperature of the aluminum substrate in the heat dissipation shell; the temperature control module is arranged in the heat dissipation shell, is arranged on the aluminum substrate and is electrically connected with the refrigeration module, and the temperature control module is used for detecting the temperature of the aluminum substrate and controlling the refrigeration module to cool the aluminum substrate; the radiation refrigeration coating is arranged on the heat dissipation shell, external solar energy can be efficiently reflected, self energy can be radiated, the heat dissipation pressure of the explosion-proof lamp is reduced, passive heat dissipation is achieved, and forced active heat dissipation is achieved by arranging the temperature control module and the refrigeration module in the heat dissipation shell.

Description

Technical Field

[0001] The present invention relates to the technical field of explosion-proof lamp heat dissipation, and in particular to an explosion-proof lamp including active and passive heat dissipation modes. Background Art

[0002] Explosion-proof lamps are a special type of lighting equipment, usually used in Sinopec scenarios, such as petroleum, chemical, mining, warehousing and other dangerous places containing flammable and explosive substances. They can be used as emergency lighting fixtures. In order to ensure the safe operation of explosion-proof lamps in emergency situations, explosion-proof lamps usually adopt a closed structure. However, in emergency situations and sealed environments, the heat dissipation capacity of explosion-proof lamps is limited, which not only affects the luminous effect of explosion-proof lamps, but also seriously reduces the service life of explosion-proof lamps. Therefore, an efficient heat dissipation measure to reasonably control the temperature of explosion-proof lamps is very important for the stable and efficient operation of explosion-proof lamps. Summary of the invention

[0003] To this end, the technical problem to be solved by the present invention is to overcome the problems in the prior art such as insufficient heat dissipation capacity of explosion-proof lamps, which leads to a short heat dissipation service life of explosion-proof lamps, and further provide an explosion-proof lamp including an active and passive heat dissipation mode, which can not only efficiently reflect external solar energy, but also radiate its own energy, thereby reducing the heat dissipation pressure of the explosion-proof lamp and realizing passive passive heat dissipation. By arranging a temperature control module and a refrigeration module inside the heat dissipation shell, forced active heat dissipation is realized.

[0004] In order to solve the above technical problems, the present invention provides an explosion-proof lamp with active and passive heat dissipation modes, comprising:

[0005] A heat dissipation shell, the exterior of which is provided with a radiation cooling coating, the radiation cooling coating comprising a substrate layer, a photonic crystal layer and a polymer layer stacked in sequence, and the radiation cooling coating radiates the energy of the heat dissipation shell to the exterior of the heat dissipation shell and reflects solar energy; the net cooling power density P of the radiation cooling coating net The calculation method is as follows:

[0006] P net =P rad (T c )-P atm (T amb )-P solar -P cond+conv (6)

[0007] Among them, P rad (T c ) is the radiator at temperature T c and the radiated power density on its hemisphere is the angular integral over the radiator hemisphere, λ is the wavelength, T c is the radiator temperature, I bb (λ,Tc ) is the black body at the radiator temperature T c The spectral radiation power density under , ε(θ,λ) is the directional spectral emissivity of the radiator. Since the radiator is opaque, according to Kirchhoff's law, the emissivity ε of the radiator is equal to the absorptivity a.

[0008] P atm (T amb ) is at ambient temperature T amb The power density of atmospheric thermal radiation absorbed is:

[0009]

[0010] Among them, ε atm (θ,λ) is the directional spectral emissivity of the atmosphere, which can be obtained by The equation is obtained, t (λ) is the atmospheric emissivity.

[0011] P solar The power density of solar radiation absorbed by the radiator under the AM1.5 standard is:

[0012]

[0013] Among them, σ represents the solar zenith angle at the time under the longitude and latitude of the test area, α(λ,σ) is the spectral absorptivity of the radiator at this zenith angle, and I AM1.5 (λ) is the solar irradiance under the AM1.5 standard.

[0014] P cond+conv =h(T amb -T C ) (10)

[0015] Among them, h is the non-radiative heat transfer coefficient. Under ideal conditions, the non-radiative heat transfer coefficient h=0. Under practical conditions, it is usually expressed as a semi-empirical formula related to wind speed: h=a+bv, where a and b are coefficients determined by the fitting results.

[0016] A refrigeration module is arranged inside the heat dissipation housing, and the refrigeration module is used for refrigeration to reduce the temperature of the aluminum substrate inside the heat dissipation housing;

[0017] A temperature control module is arranged inside the heat dissipation housing, is arranged on the aluminum substrate and is electrically connected to the refrigeration module, and is used to detect the temperature of the aluminum substrate and control the refrigeration module to cool the aluminum substrate.

[0018] In one embodiment of the present invention, the polymer layer is polydimethylsiloxane, and its thickness ranges from 50 μm to 100 μm.

[0019] In one embodiment of the present invention, the photonic crystal layer includes a first layer, a second layer and a third layer stacked in sequence, wherein the first layer is adjacent to the polymer layer; the materials of the first layer, the second layer and the third layer are SiO2, Ta2O5, MgF2, respectively, and the thickness ranges of the first layer, the second layer and the third layer are 0.75±0.05μm, 0.67±0.05μm, 0.04±0.05μm, respectively.

[0020] In one embodiment of the present invention, the material of the base layer is Ag, and the thickness of the base layer is greater than 0.2 μm.

[0021] In one embodiment of the present invention, the absorption wavelength of the radiation cooling coating is 2500-20000 nm.

[0022] In one embodiment of the present invention, the aluminum substrate is connected to the heat dissipation housing and thermal conductive silicone grease is filled between the aluminum substrate and the heat dissipation housing.

[0023] In one embodiment of the present invention, the heat dissipation housing is provided with infrared anti-reflection explosion-proof glass, and the light and infrared heat radiation of the explosion-proof lamp are emitted to the outside through the infrared anti-reflection explosion-proof glass.

[0024] In one embodiment of the present invention, an LED chip is arranged on the front side of the aluminum substrate, and the LED chip emits the light.

[0025] In one embodiment of the present invention, the external anti-reflection explosion-proof glass is configured as potassium bromide tempered glass.

[0026] In one embodiment of the present invention, the refrigeration module includes a thermoelectric material, the thermoelectric material is disposed on the back side of the aluminum substrate, and the thermoelectric material is used for refrigeration.

[0027] In one embodiment of the present invention, it also includes a copper plate abutting between the aluminum substrate and the thermoelectric material, and the copper plate is connected to the heat dissipation shell. When the temperature abnormality triggers the thermoelectric module to start, the side of the thermoelectric module close to the lamp is cooled, and the heat generated at the other end is transferred to the shell by the copper plate. The shell can achieve radiation cooling with the outside space, which is about 10°C lower than the ambient temperature, thereby taking away the heat generated by the thermoelectric module and realizing efficient cooling of the explosion-proof lamp.

[0028] In one embodiment of the present invention, the copper plate abuts against the back side of the aluminum substrate.

[0029] In one embodiment of the present invention, the temperature control module is arranged on the back side of the aluminum substrate.

[0030] In one embodiment of the present invention, the heat dissipation housing is provided with a fin structure.

[0031] The above technical solution of the present invention has the following advantages compared with the prior art:

[0032] The explosion-proof lamp with active and passive heat dissipation modes described in the present invention has a heat dissipation shell that is doped with a silver substrate and silicon dioxide microspheres or composed of a multi-layer film, which can efficiently reflect external solar energy to reduce its own heat dissipation pressure, and radiate its own internal energy in the atmospheric window band, thereby realizing passive passive cooling; the temperature control module detects the temperature of the aluminum substrate in real time, controls the refrigeration module to cool according to the detection result to reduce the temperature of the aluminum substrate, realizes forced active cooling, and ensures that the explosion-proof lamp is kept in the optimal temperature working range in real time. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings.

[0034] Figure 1 It is a structural schematic diagram of an exploded view of an explosion-proof lamp including an active and passive heat dissipation mode described in a preferred embodiment of the present invention.

[0035] Figure 2 It is a cross-sectional schematic diagram of the radiation cooling coating radiator in the present invention;

[0036] Figure 3 is a spectral emissivity diagram of the radiative cooling coating in the present invention;

[0037] Explanation of the markings in the specification: 1. heat dissipation shell; 2. power supply compartment; 3. refrigeration module; 4. temperature control module; 5. aluminum substrate; 6. LED chip; 7. infrared anti-reflection explosion-proof glass; 8. installation frame; 9. shell base; L1. polymer layer; L2. first layer; L3. second layer; L4. third layer; L5. base layer. DETAILED DESCRIPTION

[0038] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0039] Example

[0040] Reference Figure 1 As shown, in one embodiment of the present invention, an explosion-proof lamp including an active passive heat dissipation mode includes:

[0041] A power supply compartment 2, which contains a power supply;

[0042] The heat dissipation housing 1 is provided with a housing base 9, an electrical cavity and a light source cavity which are connected to each other, and a radiation cooling coating is provided on the outside of the heat dissipation housing 1. The radiation cooling coating of the thin film doped with nanoparticles is composed of a polymer layer, a photonic crystal layer and a substrate, and a total of five layers. The photonic crystal layer includes three layers, as shown in FIG. Figure 2 The figure shows a cross-sectional schematic diagram of the radiation cooling coating. The polymer layer L1 is arranged at the top layer, and its material is polydimethylsiloxane (PDMS), and its thickness ranges from 50μm to 100μm; the photonic crystal layer includes a first layer L2, a second layer L3 and a third layer L4 stacked in sequence, wherein the first layer L2 is adjacent to the polymer layer L1, and the third layer L4 is adjacent to the base layer L5. The materials of the first layer L2, the second layer L3 and the third layer L4 are SiO2, Ta2O5, and MgF2, respectively, and the thickness ranges of the first layer L2, the second layer L3 and the third layer L4 are 0.75±0.05μm, 0.67±0.05μm, and 0.04±0.05μm, respectively. The base layer L5 is made of Ag, and its thickness must be greater than 0.2μm, so as to ensure the high reflectivity of the radiator in the solar band and the opacity of the overall material. During the day, the radiation cooling coating can reflect solar energy to the outside of the heat dissipation housing 1, reducing the heat dissipation pressure inside the heat dissipation housing 1. In the atmospheric window band, the radiation cooling coating radiates the energy inside the heat dissipation housing 1 to the outside of the heat dissipation housing 1. The spectral emissivity of the radiation cooling coating varies with wavelength as shown in FIG. Figure 3 As shown, the coating realizes passive heat dissipation. The power supply compartment can be detachably connected to the top of the heat dissipation housing 1, and the power supply is connected to the electrical cavity and the light source cavity of the heat dissipation housing 1 through a power line;

[0043] The net cooling power density P net The calculation method is as follows:

[0044] P net =P rad (T c )-P atm (T amb )-P solar -P cond+conv (11)

[0045] Among them, P rad (T c ) is the radiator at temperature T c and the radiated power density on its hemisphere is the angular integral over the radiator hemisphere, λ is the wavelength, T c is the radiator temperature, I bb (λ,T c ) is the black body at the radiator temperature T cThe spectral radiation power density under , ε(θ,λ) is the directional spectral emissivity of the radiator. Since the radiator is opaque, according to Kirchhoff's law, the emissivity ε of the radiator is equal to the absorptivity a.

[0046] P atm (T amb ) is at ambient temperature T amb The power density of atmospheric thermal radiation absorbed is:

[0047]

[0048] Among them, ε atm (θ,λ) is the directional spectral emissivity of the atmosphere, which can be obtained by The equation is obtained, t (λ) is the atmospheric emissivity.

[0049] P solar The power density of solar radiation absorbed by the radiator under the AM1.5 standard is:

[0050]

[0051] Among them, σ represents the solar zenith angle at the time under the longitude and latitude of the test area, α(λ,σ) is the spectral absorptivity of the radiator at this zenith angle, and I AM1.5 (λ) is the solar irradiance under the AM1.5 standard.

[0052] P cond+conv =h(T amb -T C ) (15)

[0053] Wherein, h is the non-radiative heat transfer coefficient. In an ideal state, the non-radiative heat transfer coefficient h = 0. In actual situations, it is usually expressed as a semi-empirical formula related to wind speed: h = a + bv, where a and b are coefficients determined by the fitting results. According to the above calculation method, the cooling power density of the radiation cooling layer can be obtained as 100W / m 2 .

[0054] The above-mentioned radiation cooling coating can use an optical coating machine to sequentially evaporate the substrate and the photonic crystal layer. For the preparation of the polymer layer, the PDMS curing agent and the base material are mixed in a mass ratio of 1:10 to prepare a PDMS slurry. Then, a spin coater (EZ4) is used on top of the prepared photonic crystal layer, and the PDMS layer is evenly distributed on the photonic structure at a speed of 1600 rpm (1600 revolutions per minute). Finally, the prepared radiator is placed in a drying oven, dried at 60°C for 2 hours, and then taken out to complete the preparation of the radiator.

[0055] A refrigeration module 3 is arranged in the electrical cavity of the heat dissipation shell 1. The refrigeration module 3 cools the aluminum substrate 5 inside the heat dissipation shell 1 by refrigeration materials. The aluminum substrate 5 is installed in the light source cavity for transferring heat. The heat generated by the light source of the explosion-proof lamp is conducted to the aluminum substrate 5. The aluminum substrate 5 has good thermal conductivity.

[0056] The temperature control module 4 is arranged in the electrical cavity inside the heat dissipation shell 1, which is arranged on the aluminum substrate 5 and electrically connected to the refrigeration module 3. The temperature control module 4 is used to detect the temperature of the aluminum substrate 5 through a temperature sensor, and controls the refrigeration module 3 to cool the aluminum substrate 5 through a controller according to the detection result.

[0057] In one embodiment of the present invention, referring to Figure 1 As shown, the aluminum substrate 5 is connected to the heat dissipation housing 1 and thermal conductive silicone grease is filled between the two. The thermal conductive silicone grease is used to reduce the contact thermal resistance between the aluminum substrate 5 and the heat dissipation housing 1 and enhance heat dissipation.

[0058] In one embodiment of the present invention, referring to Figure 1 As shown, the heat dissipation shell 1 is provided with a light opening, and the light opening is provided with an infrared anti-reflection explosion-proof glass 7, and the infrared anti-reflection explosion-proof glass 7 is fixedly installed on the light opening through a mounting frame 8. The light emitted by the light source in the explosion-proof lamp is emitted to the outside through the infrared anti-reflection explosion-proof glass 7. The infrared anti-reflection explosion-proof glass 7 can increase the transmittance of the glass in the infrared band while ensuring the explosion-proof strength, so that the spontaneous infrared heat radiation of the light source can better pass through the light opening, thereby ensuring the efficient heat dissipation of the explosion-proof lamp.

[0059] In one embodiment of the present invention, referring to Figure 1 As shown, the light source includes a plurality of LED chips 6 arranged on the front side of the aluminum substrate 5, and the LED chips 6 emit the light. The front side of the aluminum substrate 5 refers to the surface close to the infrared anti-reflection explosion-proof glass 7, and the back side of the aluminum substrate 5 refers to the surface close to the power supply compartment 2.

[0060] In one embodiment of the present invention, referring to Figure 1 As shown, the external anti-reflection explosion-proof glass is set to be potassium bromide tempered glass, and the potassium bromide tempered glass is formed by doping with potassium bromide.

[0061] In one embodiment of the present invention, referring to Figure 1As shown, the refrigeration module 3 includes a thermoelectric material controlled by the temperature control module 4. The thermoelectric material is arranged on the back of the aluminum substrate 5. The thermoelectric material is used for cooling. The heat of the aluminum substrate 5 is transferred to the thermoelectric material for heat dissipation. In this embodiment, the thermoelectric material is a material that can directly convert thermal energy into electrical energy. They realize energy conversion based on the Peltier effect.

[0062] In one embodiment of the present invention, referring to Figure 1 As shown, the temperature control module 4 is arranged on the back side of the aluminum substrate 5 .

[0063] In one embodiment of the present invention, referring to Figure 1 As shown, it also includes a copper plate abutting between the aluminum substrate 5 and the thermoelectric material. The copper plate is used for uniform heat conduction to prevent local excessive temperature. The copper plate combined with the heat pipe can quickly and evenly conduct the heat generated by the LED chip 6 to the thermoelectric material.

[0064] In one embodiment of the present invention, referring to Figure 1 As shown, the LED chip 6 will generate heat, and the heat power generated can be calculated using the following formula:

[0065] P heat =P total ×(1-η) (16)

[0066] Where: P heat is the heat power generated by the LED lamp (W), P total is the total input power of the LED lamp (W), and η is the photoelectric conversion efficiency of the LED lamp (between 0 and 1). Assuming that the total input power of the LED lamp is 50W, the photoelectric efficiency of the current LED lamp is generally 30%, so the heat generated by the LED chip 6 is 35W.

[0067] In one embodiment of the present invention, referring to Figure 1 As shown, the cooling module 3 will dissipate heat from the LED chip 6. While one end of the thermoelectric material is cooling, the other end will also generate heat. The power generated by the hot end depends on the efficiency of the TEC, which is usually expressed as COP (Coefficient of Performance). COP represents the ratio of the heat absorbed by the TEC from the cold end to the power input. The following formula is used to calculate the power of the hot end:

[0068]

[0069] Among them, P hot is the power of the hot end, P heatis the heat power generated by the LED lamp, and COP is the performance coefficient of the thermoelectric material. At present, the COP of thermoelectric materials is generally 1.5, so the power of the hot end of the thermoelectric material is 58.34W.

[0070] In one embodiment of the present invention, referring to Figure 1 As shown, the exterior of the heat dissipation housing 1 is provided with a radiation cooling coating, which greatly enhances the reflectivity in the solar band during the day, reduces the absorption of solar energy by the explosion-proof lamp, and reduces the heat dissipation pressure of the LED chip 6 itself.

[0071] In one embodiment of the present invention, referring to Figure 1 As shown, the copper plate abuts against the back of the aluminum substrate 5 to evenly and quickly receive the heat of the aluminum substrate 5 .

[0072] In one embodiment of the present invention, referring to Figure 1 As shown, the heat dissipation housing 1 is provided with a fin structure, which can guide the wind flow, increase the air flow, and significantly increase the heat dissipation area and improve the heat dissipation efficiency. The heat dissipation power calculation of the fin structure involves multiple factors, including the geometric shape of the fin, the thermal conductivity of the material, the ambient temperature and the surface temperature of the fin. The following is a method for calculating the heat dissipation power of the fin structure:

[0073] Q=η·h·A·ΔT (18)

[0074] Where η is the efficiency of the fin and h is the heat transfer coefficient (W / m 2 K), A is the total heat dissipation area of ​​the fin, and ΔT is the temperature difference between the fin surface temperature and the ambient temperature. To calculate the efficiency of the fin, η depends on the geometry of the fin and the thermal conductivity of the material. Generally, the fin efficiency can be calculated using the following empirical formula:

[0075]

[0076] in, k is the thermal conductivity of the fin material, L is the length of the fin, and t is the thickness of the fin. According to the above formulas (18) and (19), the heat dissipation power of the fin structure is 270.38W, which is sufficient to meet the heat dissipation requirements of LED lights.

[0077] The working principle of the explosion-proof lamp with active and passive heat dissipation mode described in the present invention is:

[0078] During the day, the radiation cooling coating can greatly enhance the reflectivity in the solar band, reduce the absorption of solar energy by explosion-proof lamps, reduce the heat dissipation pressure of LED chip 6 itself, and achieve spontaneous and passive heat dissipation; at night, the radiation cooling coating can improve its own energy emissivity, thereby continuously transferring heat to the cosmic cold source space, and can achieve cooling of explosion-proof heat dissipation lamps without consuming any energy, thereby achieving active heat dissipation.

[0079] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. An explosion-proof lamp with active and passive heat dissipation modes, characterized in that: include, A heat dissipation shell, the exterior of which is provided with a radiation cooling coating, the radiation cooling coating comprising a substrate layer, a photonic crystal layer and a polymer layer stacked in sequence, and the radiation cooling coating radiates the energy of the heat dissipation shell to the exterior of the heat dissipation shell and reflects solar energy; A refrigeration module is arranged inside the heat dissipation housing, and the refrigeration module is used for refrigeration to reduce the temperature of the aluminum substrate inside the heat dissipation housing; A temperature control module is arranged inside the heat dissipation housing, is arranged on the aluminum substrate and is electrically connected to the refrigeration module, and is used to detect the temperature of the aluminum substrate and control the refrigeration module to cool the aluminum substrate.

2. The explosion-proof lamp with active and passive heat dissipation modes according to claim 1, characterized in that: The polymer layer is polydimethylsiloxane, and its thickness ranges from 50 μm to 100 μm.

3. The explosion-proof lamp with active and passive heat dissipation modes according to claim 1, characterized in that: The photonic crystal layer includes a first layer, a second layer and a third layer stacked in sequence, wherein the first layer is adjacent to the polymer layer; the materials of the first layer, the second layer and the third layer are SiO2, Ta2O5, and MgF2, respectively, and the thickness ranges of the first layer, the second layer and the third layer are 0.75±0.05μm, 0.67±0.05μm, and 0.04±0.05μm, respectively.

4. The explosion-proof lamp with active and passive heat dissipation modes according to claim 1, characterized in that: The material of the base layer is Ag, and the thickness of the base layer is greater than 0.2 μm.

5. The explosion-proof lamp with active and passive heat dissipation modes according to claim 1, characterized in that: The absorption wavelength of the radiation cooling coating is 2500-20000nm.

6. The explosion-proof lamp with active and passive heat dissipation modes according to claim 1, characterized in that: The aluminum substrate is connected to the heat dissipation housing and thermal conductive silicone grease is filled between the two.

7. The explosion-proof lamp with active and passive heat dissipation modes according to claim 1, characterized in that: The heat dissipation housing is provided with infrared anti-reflection explosion-proof glass, and the light and infrared heat radiation of the explosion-proof lamp are emitted to the outside through the infrared anti-reflection explosion-proof glass.

8. The explosion-proof lamp with active and passive heat dissipation modes according to claim 7, characterized in that: It includes an LED chip arranged on the front side of the aluminum substrate, and the LED chip emits the light.

9. The explosion-proof lamp with active and passive heat dissipation modes according to claim 7, characterized in that: The external anti-reflection explosion-proof glass is configured as potassium bromide tempered glass.

10. The explosion-proof lamp with active and passive heat dissipation modes according to claim 1, characterized in that: The refrigeration module includes a thermoelectric material, which is arranged on the back of the aluminum substrate and is used for refrigeration.

11. The explosion-proof lamp with active and passive heat dissipation modes according to claim 10, characterized in that: It also includes a copper plate abutting between the aluminum substrate and the thermoelectric material, and the copper plate is connected to the heat dissipation housing.

12. An explosion-proof lamp with active and passive heat dissipation modes according to claim 11, characterized in that: The copper plate is in contact with the back surface of the aluminum substrate.

13. The explosion-proof lamp with active and passive heat dissipation modes according to claim 1, characterized in that: The temperature control module is arranged on the back side of the aluminum substrate.

14. The explosion-proof lamp with active and passive heat dissipation modes according to claim 1, characterized in that: The heat dissipation housing is provided with a fin structure.

15. The explosion-proof lamp with active and passive heat dissipation modes according to claim 1, characterized in that: The net cooling power density P of the radiative cooling coating net The calculation method is as follows: P net =P rad (T c )-P atm (T amb )-P solar -P cond+conv (1) Among them, P rad (T c ) is the radiator at temperature T c and the radiated power density on its hemisphere is the angular integral over the radiator hemisphere, λ is the wavelength, T c is the radiator temperature, I bb (λ,T c ) is the black body at the radiator temperature T c The spectral radiation power density under , ε(θ,λ) is the directional spectral emissivity of the radiator. Since the radiator is opaque, according to Kirchhoff's law, the emissivity ε of the radiator is equal to the absorptivity a. P atm (T amb ) is at ambient temperature T amb The power density of atmospheric thermal radiation absorbed is: Among them, ε atm (θ,λ) is the directional spectral emissivity of the atmosphere, which can be calculated by ε atm (θ,λ)=1-t (λ) 1 / cosθ The equation is obtained, t (λ) is the atmospheric emissivity. P solar The power density of solar radiation absorbed by the radiator under the AM1.5 standard is: Among them, σ represents the solar zenith angle at the time under the longitude and latitude of the test area, α(λ,σ) is the spectral absorptivity of the radiator at this zenith angle, and I AM1.5 (λ) is the solar irradiance under the AM1.5 standard. P cond+conv =h(T amb -T C ) (5) Among them, h is the non-radiative heat transfer coefficient. Under ideal conditions, the non-radiative heat transfer coefficient h=0. Under practical conditions, it is usually expressed as a semi-empirical formula related to wind speed: h=a+bv, where a and b are coefficients determined by the fitting results.

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