The Influence of Air Humidity on Convective Cooling Conditions of Electronic Devices

The aim of this paper is to demonstrate the impact of ambient air humidity on the efficiency of heat sink operation. It was observed that increased air humidity enabled higher power dissipation in a transistor used as a test device, without increasing its junction temperature. The presented simulation results are showing a correlation between air humidity and an estimated heat flux value. The paper also contains a mathematical analysis of humidity impact on the convective heat transfer coefficient. The natural convection phenomena are visualized in different infrared spectral ranges. A multispectral approach revealed that this convective air flow is best viewed in the MWIR spectral range.