Prior studies have shown that electric field in the form of corona wind can be used for gas pumping and heat transfer enhancement. This enhancement is analyzed numerically by a two stage electrohydrodynamic (EHD) gas pump in a square channel. The 3D governing equations for electric, flow and temperature fields are solved by finite difference and finite volume methods, respectively. This study is implemented for a two stage EHD gas pump with 8 emitting electrodes configuration to seek their effectiveness in the heat transfer enhancement and pumping power requirement. The EHD gas pump is evaluated for a wide range of operating voltages starting from 20 kV up to 28 kV. The influence of electric field on the flow and temperature fields is also examined for a wide range of Reynolds numbers. The Reynolds numbers (Re) considered in this study varies in a range between 100 and 2000. At Re = 100, a maximum increase of average Nusselt number is achieved with an applied voltage of 28 kV. The pumping power required for the heat transfer enhancement is also critically evaluated. The enhancement produced by the EHD gas pump is found to be higher than other techniques and with a smaller power penalty. The overall effectiveness of the EHD gas pump in heat transfer enhancement is evaluated by the thermal hydraulic performance parameter, (Nu/Nu₀)/(f/f₀), which is always greater than unity. These results disclose that EHD technique has a great potential for many engineering applications, particularly for thermal management.
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