Cone-jet Characteristics of Ethanol by Electrospraying Using Double Electrodes

doi:10.3901/JME.2016.12.158

Abstract

Abstract: In order to design a micro-scale electrospraying combustor reasonably, some experiments of electrospraying are carried out using liquid ethanol as fuel. A stable cone-jet mode is obtained based on the new combustor mainly consisting of a capillary, a ring electrode and a stainless steel grid. The electrospraying mode is visualized, cone angle and voltage are measured. The comparison is performed between with those of single capillary electrode combustor. The effect of ring electrode on cone-jet mode is discussed. The stress distribution on the cone surface is analyzed in the electrospraying cone-jet mode. Based on the force equilibrium on the vertical surface of cone, the mechanical model is established. According to hyperboloidal model, the semi-cone angle is calculated theoretically. The results show that the fluid acquires a stable shape when the voltage reached a certain value, the critical semi-cone angle is far less than the Taylor angle of 49.3^o, closer to the theoretically calculated value of 34.72^o. Under the same spraying mode, the cone formed using double electrodes combustor is less than that formed using single electrode combustor. The capillary electrode voltage can be significantly reduced when adopting the double electrodes combustor and choosing an appropriate ring electrode voltage, which can enhance the formation of stable cone-jet.

Key words: cone-jet mode, double electrodes, electrospraying, hyperboloidal model, mechanical model

CLC Number:

TK16

GAN Yunhua, ZHANG Xia, TONG Yang, CHEN Xiaowen, YANG Zeliang. Cone-jet Characteristics of Ethanol by Electrospraying Using Double Electrodes[J]. Journal of Mechanical Engineering, 2016, 52(12): 158-164.

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