Analysis and modelling of unsteady shock train motions. (4th May 2018)

• Record Type: Journal Article
• Authors: Xiong, Bing; Fan, Xiao-qiang; Wang, Zhen-guo; Tao, Yuan
• Is Part Of: Journal of fluid mechanics. Volume 846(2018)
• Page Start: 240
• Page End: 262
• Publication Date: 2018-05-04
• Subjects: gas dynamics, -- high-speed flow, -- shock waves; Fluid mechanics -- Periodicals; 532.005
• DOI: 10.1017/jfm.2018.209
• Languages: English
• ISSNs: 0022-1120

Abstract

Abstract : The characteristics and mechanism for unsteady shock train motions were experimentally studied in a constant-area rectangular duct. High-speed Schlieren techniques and high-frequency pressure measurements were utilized in this research. The results show that the shock train undergoes periodical motions in response to downstream periodical excitations. The mechanism for unsteady shock train motions is that the shock train keeps changing its moving speed to change the relative Mach number ahead of shock train to match the varying back-pressure condition. It can be found that the unsteady shock train motion can be predicted well with a theoretical model, which is based on this mechanism. A correlation between the amplitude of shock train motions and some flow parameters was illustrated using an analytical equation, which was confirmed by the experimental results.