Experimental Study of Nozzle Electrohydrodynamic Gas Pump

• Main Authors: Jyun-Han Lin, 林均翰
• Other Authors: Sheam-Chyun Lin
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/94661894258009371203

碩士 === 國立臺灣科技大學 === 機械工程系 === 104 === In this study, an electrohydrodynamic (EHD) gas pump fitted within a linear nozzle with different diameter ratios (DR) has been tested for a wide range of applied voltages starting from the corona threshold voltage up to 17 kV for the further improvement in its performance. The EHD gas pump has been critically evaluated by experimental measurements to reveal the relation between pump performance and diameter ratio (DR) as well as the velocity profile at downstream of the pump exit. The result shows that three nozzle configurations have their own characteristics and performs differently under various conditions. A pump with a diameter ratio of 1/2 performs the best in maintaining a velocity profile that can extend the longest distance downstream of the pump while a pump with a diameter ratio of 1/4 can produce the highest velocity with the smallest increase in corona current. It is also worthwhile to note that the maximum velocity, volume flow rate, and performance produced by a pump with a diameter ratio of 1/3 are somewhat between the other two, but the current it required is the highest among all. For the present study, the best performance (in terms of the volume of air delivered by a unit energy input) of 3 L/min/W has been achieved by an EHD gas pump with a diameter ratio of 1/2 operated at 15 kV. Most important of all, it has been found that the flow and electric characteristic are not totally determined by the configuration of nozzle (i.e., the diameter ratio). As such, the design consideration of EHD gas pump fitted within a nozzle should include other parameters (such as the number of electrodes, electrode spacing, and nonlinear surface profile) for its best performance.