Flame characteristics of alcohol electro-spraying in counter-flow combustor

YE Hongcheng1,2 GAN Yunhua1,2 JIANG Zhengwei1,2 LUO Yanlai1,2

(1.School of Electric Power, South China University of Technology, Guangzhou, Guangdong, China 510640)
(2.Key Laboratory of Efficient and Clean Energy Utilization of Guangdong Province, Guangzhou, Guangdong, China 510640)
【Knowledge Link】air–fuel ratio

【Abstract】Studying the flame characteristics of atomized liquid fuel combustion helps to understand the entire combustion process. A new counter-flow combustor based on the technology of electro-spraying was designed. Experiment studies on electro-spraying shape and flame characteristics were carried out using alcohol as fuel. The primary focus is paid on the effects of strain rate and equivalent ratio on flame characteristics at different fuel flow rate, including flame temperature and dimensionless diameter of the flame. The results show that the boundary between atomized core regions and satellite regions of the spray gradually disappears when the alcohol flow rate is increased. The liquid column of spray appears when fuel flow rate reaches 13 mL/h. The flame remains stable when the equivalent ratio is less than 1 but oscillates when the equivalent ratio is more than 1. The dimensionless diameter of the flame decreases with increasing equivalent ratio. As the strain rate increases, the dimensionless diameter of the flame and the temperature decrease.

【Keywords】 gas-liquid flow; fuel; alcohol; electro-spraying; counter-flow flame; spray shape; flame characteristics;

【DOI】

【Funds】 National Science Foundation of China (51776077) China Postdoctoral Science Foundation (2019M652890) Fundamental Research Funds for the Central Universities of Ministry of Education of China (2018ZD05)

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(Translated by SUN Z)

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This Article

ISSN:0438-1157

CN: 11-1946/TQ

Vol 70, No. 12, Pages 4787-4794+4514

December 2019

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Article Outline

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Abstract

  • Introduction
  • 1 Experimental system
  • 2 Experimental procedure and data processing
  • 3 Results and analysis
  • 4 Conclusions
  • Symbols
  • References