Abstract
Heat transfer enhanced by electrohydrodynamics (EHD) is experimentally investigated in this work. The system of heat sinks with EHD can effectively increase the rate of heat transfer under natural convection due to the corona wind generated by EHD. The design of electrodes in the system of heat sinks with EHD is studied according to the required voltage and power consumption. The maximum heat transfer coefficient with EHD is greater than that without EHD by four and half times within the operating voltage range of 0 ~ 18kV. The results reveal that both the heat transfer rate and threshold voltage for negative corona are better than those for positive one. For a fixed voltage, the optimal density of electrodes depends on the height of electrode position. The area of heat removal for EHD will be limited by a small density of electrodes or the configuration of heat sinks. However, form the viewpoint of power consumption, the great density of electrodes will result in the flow recirculation and the local flow perturbation; thereby reduce the heat transfer rate. Both the voltage and power consumption must be considered in the design of EHD system.