Eur. Phys. J. D (2016) 70: 71
https://doi.org/10.1140/epjd/e2016-60696-5

Regular Article

Role of water and discharge mode on modulating properties in an atmospheric air MHCD jet^*

¹ The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing University, No. 174 Shazheng Street, Shapingba, Chongqing 400044, P.R. China
² School of Photoelectric Engineering, Chongqing University of Posts and Telecommunications, Nan’an District, Chongqing 400065, P.R. China

^a e-mail: Liukun@cqu.edu.cn

Received: 8 December 2015
Received in final form: 30 January 2016
Published online: 5 April 2016

Abstract

A portable micro hollow cathode discharge (MHCD) device was designed in this paper to generate water-air plasma jet. The results showed that MHCD jet pattern was changed from self-pulsing discharge mode to DC mode with the increasing of voltage, and the critical voltage value of discharge mode increased with the rise of gas flow. In order to study the influences of discharge mode and water content on MHCD jet, the electrical characteristics and radicals were all measured in different conditions. We found that the length of jet decreased and temperature increased with raising water-air ratio, and during self-pulsing discharge mode, •OH content was extremely low because of the low energy of electron, but level of NO was raised with gradually increasing applied voltage. In DC mode, the results showed there was least NO content, on the other hand •OH content increased with rise of voltage and water-air ratio. O existed in both discharge modes and the effect of water content on the O production was complex.