Thermal Simulation And Analysis On Optical-thermal Coupling Of LED Headlamp

This paper sets forth the theory basis of the optical design principle,the basis of heat dissipation design,and analyzes the general heat dissipation method and its calculation principle.The effect of light absorption/reflection on the thermal conductivity of the alumized coating of the reflector is related to the thickness based on the microscopic principle of photothermal effect.The critical film thickness is discussed and the thermal conductivity of the different thicknesses of the reflective coating is analyzed for a transmissive material,the refraction and absorption of light from a medium,the lens of different materials,and the selective absorption of light of different wavelengths are also different.Finally,an optical mathematical model and a mathematical model of heat transfer are established.The Monte Carlo ray tracing method is used to calculate the energy distribution on the optics such as the reflector,and the optical results are imported into the thermal coupling for calculation.The temperature of the object is tested and compared with the simulation results to verify the accuracy of the calculation.The addition of photothermal effect analysis in thermal analysis can obtain a more accurate temperature field,which has reference significance in other aspects.1)Rough calculations do not take into account the photothermal problem.If it is far between the LED and the part,the influence of the optical radiation may not be considered in the rough analysis calculation.2)The non-uniformity of the spatial energy distribution of the LED illumination cannot be directly used by software such as fluency,and the radiation physical model carried by itself directly memory the thermal influence of the light.3)Simulation analysis and test results show that the temperature distribution on the reflector has a certain gradient,that is,the "hot spot" on the temperature distribution.It provides a valuable reference to the material selection and surface treatment of the reflector.4)According to the idea of the photothermal coupling calculation method,it can be applied to the calculation of the photothermal problem of any part.It can also be applied to the calculation of light and heat on the aluminized frame of the light source module to the periphery,or to the calculation of physical phenomena such as burning of parts by sunlight.