8th Thermal and Fluids Engineering Conference (TFEC)
EXPERIMENTAL STUDY OF A TWO STAGE EHD GAS PUMP IN A SQUARE CHANNEL
Earlier studies have shown that EHD gas pump is effective for gas pumping. Fluid flow generated by a two stage EHD (electrohydrodynamic) gas pump in a square channel has been experimentally investigated for its potential in the enhancement of gas pumping. This study is implemented by a two stage EHD gas pump 4 emitting electrodes in each stage to seek the relation between the number of stages and applied voltages. The EHD pump is evaluated for a combination of three different operating voltages (20 kV, 24 kV, and 28 kV) for further enhancement in its performance. To achieve the maximum enhancement in gas pumping, the emitting electrodes are flush mounted on the channel walls so that the induced flow produced directly disturbs the boundary layer thickness. This is leading to a higher velocity near the channel walls and resulting in an inverted parabolic velocity profile at the center of the channel, which is opposite to the fully developed velocity profile of a forced flow. Fluid velocities are measured at three cross-sections along the channel length and then integrated to obtain the volume flow rate. In addition to the volume flow rate produced, the performance of the pump is evaluated using an energy efficiency factor. The two stages EHD gas pump, which can be produced and sustained air flows with a maximum volume flow rate is considered more efficient when it is operated with uneven applied voltages. The results show that EHD technique has a great potential for many engineering applications.