NUMERICAL AND EXPERIMENTAL INVESTIGATIONS ON MINI CHANNEL LIQUID METAL COOLERS FOR POWER SEMICONDUCTOR DEVICES

The need to adopt new cooling techniques arouse because of the continuous increase in power dissipation of electronic parts and systems. Due to the low thermal conductivity of classical liquids (water, alcohols, dielectric fluid, etc.), in many cases, the standard liquid cooling techniques cannot achieve the required cooling performances. This paper deals with power semi conductor devices (IGBT, MOSFET or diodes) cooling. The major problem of those power components is that they can easily dissipate several hundreds W.cm-2. Thus their cooling needs very high heat transfer coefficients. Therefore we introduce the use of liquid Ga alloys whose thermal conductivity (approx. 28Wm-1K-1) is 40 times greater than thermal conductivity of water. In this paper a numerical modeling and an experimental study of liquid metal mini channel coolers are presented. In the experimental cooling loop the working fluid (Ga alloy) is moved via an electromagnetic pump. The values of the convection coefficient obtained by the numerical model are compared with the correlations founded in the bibliography and the experimental data.