NUMERICAL INVESTIGATION ON COOLING OF A HEATED PLATE WITH HOT SPOTS USING ELECTROSTATIC AIR ACCELERATORS
Air cooling is one of the most important cooling solutions for microelectronics because the last step of heat exchange with ambient environment remains necessary. However, conventional rotary fans cannot meet the requirements for microelectronics cooling. Electrostatic air accelerators offer an attractive alternative to fans and have shown great potential in applications of devices cooling due to advantages of low energy consumption, no moving parts and compact structure. In this paper, a 3-D model of electrostatic air accelerator is established using finite element method. The impinging flow of the accelerator is used to cool down a heated plate with hot spots. Effects of heat flux, hot spot size, eccentric distance and hot spot number are analyzed. With increasing hot spot heat flux, there is a sudden change in the increasing slope of maximum temperature of the plate, which is caused by different locations of maximum temperature. The cooling effect is better with smaller hot spot because less heat is added into the plate by increasing unit heat flux of hot spot. The heat transfer characteristics of the stagnation area are better than the surrounding area, so the cooling capacity drop down with larger eccentric distance of the hot spot. Besides, with more hot spots, the cooling capacity slightly reduces. This study provides a reference for the practical cooling process of commercial chips with hot spots using electrostatic air accelerators.