Analysis of Natural Convection inside an Automotive Headlamp by Using CFD - Temperature Prediction of the Parts by SHT Method

In order to improve thermal endurance, mechanical durability and ventilation performance in a headlamp, it is important to understand heat transfer and flow in an automotive headlamp. Especially in a design stage, understanding natural convection inside the headlamp will make it possible to shorten its development period, which can be fulfilled by Computational Fluid Dynamics (CFD). In the present study, a newly-developed method called Surface Heat Transfer (SHT) method, that is a unique technique for making an accurate estimate of temperature and velocity in the automotive headlamp without involving the couple of the fluid mechanics and the structural mechanics (the coupled fluid solid interaction), was investigated for practical use. An evaluation of SHT method was performed, and CFD results were compared with the experimental results. Consequently, the temperature results by CFD were within ±10 degrees as compared with the experimental results.