Experimental study on a sinusoidal air/SF$_{6}$ interface accelerated by a cylindrically converging shock. (14th August 2017)

• Record Type: Journal Article
• Authors: Lei, Fan; Ding, Juchun; Si, Ting; Zhai, Zhigang; Luo, Xisheng
• Is Part Of: Journal of fluid mechanics. Volume 826(2017)
• Page Start: 819
• Page End: 829
• Publication Date: 2017-08-14
• Subjects: compressible flows, -- instability, -- mixing; Fluid mechanics -- Periodicals; 532.005
• DOI: 10.1017/jfm.2017.506
• Languages: English
• ISSNs: 0022-1120

Abstract

Abstract : Ritchmyer–Meshkov instability on an air/SF $_{6}$ interface is experimentally studied in a coaxial converging shock tube by a high-speed laser sheet imaging technique. An unperturbed case is first examined to obtain the characteristics of the converging shock and the shocked interface. For sinusoidal interfaces, the wave pattern and the interface morphology of the whole process are clearly observed. It is quantitatively found that the perturbation amplitude first decreases due to the shock compression, then experiences a rapid growth to a maximum value and finally drops quickly before the reshock. The reduction of growth rate is ascribed to the Rayleigh–Taylor stabilization caused by the interface deceleration motion that is present in the converging circumstance. It is noted that the influence of the wavenumber on the amplitude growth is very little before the reshock, but becomes significant after the reshock.