Study About The Key Techniques Of Thermal Design And Fogging Rule For Automotive Lamps

With the continuous development of the automotive lights industry,more and more attentions of thermal design of lights were put by engineering staffs.So far,however,the fogging inside the lights is still an important issue which seriously affects the quality of the lights.If the temperature of lamp's part is too high,it will cause the plastic to soften,on the other hand,if the temperature is too low,it is likely to cause problems of fogging lights,which seriously affect the driver's sight,threatening the safety of human's life.Therefore,it is necessary to analyze the problem of heating lamp.In this paper,I use the knowledge of heat transfer,thermodynamics and other disciplines as the theoretical basis,through using theoretical analysis,finite element simulation and experimental verification methods to simulate the temperature field distribution of the various components of the lights and air flow to get the reason of lights fogging,and to solve problems and verified lights fogging issue by experiment.(1)Research on simulation modeling of heating lamp.According to the structural characteristics and the work states of lights,headlight simplified modeling strategy has been studied to explore the heat transfer between the various components in the form of lights,the flow field boundary conditions are given when the lights was lit,though the establishment of an effective and feasible Heat lamps simulation models.(2)Lights' airflow and temperature field simulation.Through the lamp which companies are eager to solve the problem of car headlights as the research object,the lights heat simulation model established based on the temperature and flow field inside lights were simulated and discussed the problem of temperature and interior lights distribution of the flow field,to find the area which is easy to appear fog inside the light.(3)Combining the theory of engineering thermodynamics,the underlying causes fogging lights was analyzes: the lights' low temperature area's air temperature is below the dew point temperature of the lamp parts of the surface,pointing out that the lights internal temperature,velocity distribution are the major factors to affect lights fogging.On this basis,the concept of zoning dew point lights was proposed,giving a convenient and practical criterion fogging lights,and for the lights,in order to prevent fogging issues,designers should pay attention to the lights.(4)The problem lights lit experiment was done,obtaining the temperature of the lightswhen in lit work,and with the results of the simulation conducted to verify the reliability and validity of the simulation results.