中国物理B ›› 2018, Vol. 27 ›› Issue (9): 94705-094705.doi: 10.1088/1674-1056/27/9/094705

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Shock oscillation in highly underexpanded jets

Xiao-Peng Li(李晓鹏), Rui Zhou(周蕊), Xiao-Ping Chen(陈小平), Xue-Jun Fan(范学军), Guo-Shan Xie(谢国山)   

  1. 1 China Special Equipment Inspection and Research Institute, Beijing 100029, China;
    2 Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100094, China;
    3 Key Laboratory of Fluid Transmission Technology of Zhejiang Province, Zhejiang Sci-Tech University, Hangzhou 310018, China;
    4 State Key Laboratory of High Temperature Gas Dynamics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
  • 收稿日期:2018-02-26 修回日期:2018-06-06 出版日期:2018-09-05 发布日期:2018-09-05
  • 通讯作者: Xiao-Peng Li E-mail:lxpyfy@163.com
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant No. 11602028) and the Science and Technology Project of General Administration of Quality Supervision Inspection and Quarantine of China (Grant Nos. 2017QK119 and 2017QK188).

Shock oscillation in highly underexpanded jets

Xiao-Peng Li(李晓鹏)1, Rui Zhou(周蕊)2, Xiao-Ping Chen(陈小平)3, Xue-Jun Fan(范学军)4, Guo-Shan Xie(谢国山)1   

  1. 1 China Special Equipment Inspection and Research Institute, Beijing 100029, China;
    2 Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100094, China;
    3 Key Laboratory of Fluid Transmission Technology of Zhejiang Province, Zhejiang Sci-Tech University, Hangzhou 310018, China;
    4 State Key Laboratory of High Temperature Gas Dynamics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
  • Received:2018-02-26 Revised:2018-06-06 Online:2018-09-05 Published:2018-09-05
  • Contact: Xiao-Peng Li E-mail:lxpyfy@163.com
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant No. 11602028) and the Science and Technology Project of General Administration of Quality Supervision Inspection and Quarantine of China (Grant Nos. 2017QK119 and 2017QK188).

摘要:

The oscillatory motions of shocks in highly underexpanded jets with nozzle pressure ratios of 5.60, 7.47, 9.34, and 11.21 are quantitatively studied by using large eddy simulation. Two types of shock oscillations are observed:one is the Mach disk oscillation in the streamwise direction and the other is the shock oscillation in the radial direction. It is found that the Mach disk moves quickly in the middle of the oscillatory region but slowly at the top or bottom boundaries. The oscillation cycles of Mach disk are the same for different cases, and are all dominated by an axisymmetric mode of 5.298 kHz. For the oscillation in the radial direction, the shocks oscillate more toward the jet centerline but less in the jet shear layer, and the oscillation magnitude is an increasing function of screech amplitude. The cycles of the radial shock oscillation switch randomly between the two screech frequencies for the first two cases. However, the oscillation periodicity is more complex for the jets with high nozzle pressure ratios of 9.34 and 11.21 than for the jets with the low nozzle pressure ratios of 5.6 and 7.47. In addition, the shock oscillation characteristics are also captured by coarse mesh and Smagorinsky model, but the coarse mesh tends to predict a slower and weaker shock oscillation.

关键词: highly underexpanded jets, shock oscillation, large eddy simulation

Abstract:

The oscillatory motions of shocks in highly underexpanded jets with nozzle pressure ratios of 5.60, 7.47, 9.34, and 11.21 are quantitatively studied by using large eddy simulation. Two types of shock oscillations are observed:one is the Mach disk oscillation in the streamwise direction and the other is the shock oscillation in the radial direction. It is found that the Mach disk moves quickly in the middle of the oscillatory region but slowly at the top or bottom boundaries. The oscillation cycles of Mach disk are the same for different cases, and are all dominated by an axisymmetric mode of 5.298 kHz. For the oscillation in the radial direction, the shocks oscillate more toward the jet centerline but less in the jet shear layer, and the oscillation magnitude is an increasing function of screech amplitude. The cycles of the radial shock oscillation switch randomly between the two screech frequencies for the first two cases. However, the oscillation periodicity is more complex for the jets with high nozzle pressure ratios of 9.34 and 11.21 than for the jets with the low nozzle pressure ratios of 5.6 and 7.47. In addition, the shock oscillation characteristics are also captured by coarse mesh and Smagorinsky model, but the coarse mesh tends to predict a slower and weaker shock oscillation.

Key words: highly underexpanded jets, shock oscillation, large eddy simulation

中图分类号:  (Turbulent jets)

  • 47.27.wg
47.60.Kz (Flows and jets through nozzles) 47.40.Nm (Shock wave interactions and shock effects) 47.27.ep (Large-eddy simulations)