Research On Key Technologies Of Thermal Design Of LED Automotive Headlamps

With the vigorous development of the automobile industry and the increasing traffic density,driving safety has become a problem that cannot be ignored.As the crowning touch of the car,the headlights are becoming more and more important,and the design requirements for the headlights of the car companies are becoming more and more strict.Traditional halogen source headlamps have been unable to meet market requirements.The new LED(Light Emitting Diode)light source has been gradually recognized and affirmed by the market due to its many advantages such as good light efficiency,long life,energy saving and environmental protection,and small size.The thermal design of LED lights has two problems.On the one hand,the excessive temperature of LED lights will lead to lower luminous efficiency and greatly shortened service life.On the other hand,due to the popularity of LEDs,more lenses have been applied.The lamp is facing problems such as burning of the sun,Therefore,the thermal design of LED car headlights is particularly important.Based on the knowledge of heat transfer,computational fluid dynamics and geometric optics,this paper studies the problems of heat dissipation and sunlight exposure of LED headlamps,applying theoretical analysis,finite element simulation and experimental verification.(1)Research on simulation modeling methods for LED headlamps Modeling and properly improving the LED headlamps of a certain type of vehicle,focusing on the pre-processing modeling method of LED lights,and establishing a LED headlamp calculation model suitable for the solver according to the heat transfer process.Explain the adaptability of LED headlamps to simplify modeling methods.(2)Under the condition of natural convection,the simulation performance of LED headlights is studied.The simulation method of LED headlamp cooling is studied to obtain the distribution of temperature field and flow field when LED headlamps are lighting.Study the influence of LED heat sink substrate and heat sink material parameters on heat dissipation performance,compare and analyze key component materials,and provide some reference for LED lamp thermal design.(3)Aiming at the problem that LED headlamps are concentrated under sunlight radiation,a method of using optical tracking software to simulate different angles of sunlight and risk surface energy distribution is proposed,and based on the established LED headlamp radiation model.Simulate and improve the temperature field distribution of the concentrating area under the sunlight radiation of the headlights.(4)Design the experimental scheme,select the simulation verification method according to the actual working characteristics of the LED lights,and conduct temperature measurement and solar radiation experiment on a certain LED headlight source.The accuracy of the headlamp thermal simulation modeling method is verified by error and appearance analysis.In summary,this paper mainly studies the heat dissipation design of high-power LED headlamps and the simulation method of solar radiation simulation.It analyzes the temperature field and internal flow of LED headlamps,and LED frontlights under sunlight radiation conditions.The method of judging the sunlight concentration of the lamp,the energy distribution and the temperature field distribution.This research provides a certain reference for the optimization of the headlight thermal design,which is beneficial to improve the design quality and service life of LED automotive headlamps.