导航

ACTA AERONAUTICAET ASTRONAUTICA SINICA ›› 2019, Vol. 40 ›› Issue (12): 123224-123224.doi: 10.7527/S1000-6893.2019.23224

• Fluid Mechanics and Flight Mechanics • Previous Articles     Next Articles

Influence of microwave on structure of supersonic combustion flame

MENG Yu1,2, GU Hongbin2, ZHANG Xinyu1,2   

  1. 1. School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China;
    2. The State Key Laboratory of High Temperature Gas Dynamics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
  • Received:2019-06-18 Revised:2019-06-27 Online:2019-12-15 Published:2019-07-15
  • Supported by:
    National Natural Science Foundation of China (11772342)

Abstract: Plasma assisted combustion in supersonic flow is a promising method. The effect of microwave on the flame structure is studied by feeding low-power microwave into the combustor of the scramjet. The combustor inlet flow Mach number is 2.5. Room temperature ethylene is injected perpendicular to the combustor wall. Single stage cavity is used as flame stabilizer, and 500 W and 700 W continuous 2.45 GHz microwave are added into the combustor. A high-speed camera is used to capture flame CH* illuminating images. After the addition of microwave, the stable position of the flame changes from cavity shear layer flame to jet flame, which indicates that the microwave has an effect on the flame propagation speed or the combustion reaction rate. Using the method of flame boundary extraction and fractal geometry, this paper finds that microwave can increase the fractal dimension of flame boundary, indicating that the propagation rate of flame increases due to the addition of microwave. The paper concludes that a low power of microwave can assist supersonic combustion.

Key words: scramjet, supersonic combustion, flame structure, microwave, flame boundary, fractal geometry

CLC Number: