Comparative study of cooling of automobile LED headlights without and with fins and finding comfortable operating conditions

LED light must be cooled to avoid reaching a certain temperature. Two different 3D practical domains of LED light are modelled, (i) square aluminium plate with a cylindrical plate and an LED module (model I), (ii) the same provision of model I with 25 fins (model II). ANSYS 16.0 is used for solving the problem. Temperature distribution, junction temperature (Tj ) and heat flux are estimated. Analyses are carried out for various ambient temperatures (Ta) and for different LED power dissipations (Q) to identify the safe operating conditions. In model I, it is found that 38% of working conditions go beyond the critical limit of Tj and it is reduced to 21.4% in model II. In model II, for low Ta of 30 and 40 C with all Q considered in this analysis are safer. If Ta is between 30 and 80 C, then Q must be maintained at 0.5 to 1.25 W. Beyond this, conditions are not safe.