Three-dimensional shock wave distortion in shock-square vortex loop interaction

Abstract

Abstract:Understanding of the three-dimensional shock wave-vortex loop interaction phenomena plays a key role in noise reduction. This study focuses on the three-dimensional shock wave distortion and propagation phenomena in a near-field supersonic jet. Shock-square vortex loop interaction was experimentally investigated in a square cross-sectional open-end shock wave generating tube at an incident shock Mach number of 1.39 ± 0.05. A square vortex loop impinged on a reflected shock wave from a wall located in front of the nozzle end. The planar reflected shock wave transforms into either a concave or convex distorted shape due to the opposing high-speed flow emitted from the nozzle corner. The convex shaped shock wave scatters towards the outside of the vortex loop, whereas the concave one converges towards the centre of the vortex loop. The concave shaped shock wave results in shock wave focusing. In shock-square vortex loop interaction, the shock wave is locally focused along the axis of the nozzle corner. Keywords:Shock wave interaction; square vortex loop; shock wave focusing 2

On the propagation and multiple reflections of a blast wave travelling through a dusty gas in a closed box

“…9 Because of the hazardous nature of such events, an accurate assessment of the areas invaded by the flows and a quantitative estimate of their destructive actions (in terms of such measures as temperature and dynamic pressure) is of great importance for civil protection purposes. 10 Most previous studies have focused essentially on the "shock-tube" problem, given the undeniable advantages offered by this specific configuration, which can be regarded as very versatile shortduration facilities [11][12][13][14][15][16][17][18][19] Sommerfeld 6 was the first to attack the problem experimentally by studying directly the attenuation of a shock as it propagates into a gas-particle mixture. A number of tests were conducted at different initial shock speeds M s and particle loadings.…”

Characterization of a novel open-ended shock tube facility based on detonation transmission tubing

“…The shock wave produces a high pressure and a high temperature as well as induced high speed flow. Since the magnitude of these flow features depends on the initial pressure ratio between the driver and driven sections as well as the specific heat ratio of gas medium, shock tubes can be used to study aerodynamic flows in a wide range of temperatures and pressures, which are difficult to obtain in other types of testing facilities [4][5][6][7][8][9][10][11][12][13][14][15][16]. Additionally, shock tubes are applicable to fundamental research in medicine, biology, and industries [17][18][19][20][21][22][23].…”

“…The present study proposes and demonstrates a novel concept to design the shock tube using a commercially available and cost-effective detonation transmission tubing. The detonation transmission tubing had been applied to generate micro-blast waves or small-scale explosion in previous studies [12,28,29]. Additionally, Ukai et al [12] used the shock tube driven by a high pressure explosion gas produced from the detonation transmission tubing for the first time to investigate shock wave distortion in shock-square vortex loop interaction.…”

“…The detonation transmission tubing had been applied to generate micro-blast waves or small-scale explosion in previous studies [12,28,29]. Additionally, Ukai et al [12] used the shock tube driven by a high pressure explosion gas produced from the detonation transmission tubing for the first time to investigate shock wave distortion in shock-square vortex loop interaction. However, the working principle of the detonation transmission tubing driven shock tube and capabilities of this type of the shock tube have not been investigated yet.…”