Automotive Headlamp - Analytic Solution and Measurements of Condensation Inside a Headlamp

E. Preihs
General Motors Europe, Sweden

Dew points higher than the inner surface temperature of a headlight can become cosmetic problems.

In this paper, a suggested analytical approach of dew point analysis in headligths is brought forward. The analytical solution is based on a temperature map consisting of heat transfer, natural convection and radiation. An empirical expression for relative humidity is then implemented based on the calculated temperature map.

Comparison between analytical results and measured temperatures, relative humidity and dew points, calculated using the Magnus-Tetens formula, show realistic results for the model.