Vortex Ring Interaction Studies with a Cylinder and a Sphere

Abstract

*† ‡ § ** An experimental study has been conducted to examine the interaction of a shock wave and a vortex ring with a cylinder and a sphere. The experiments were carried out using a 30mm internal diameter shock-tube. The driver and driven gas was air. High-speed Schlieren photography was employed to study the development of the flow-field and the resulting interactions with the body configurations. Wall pressure measurements were also carried out to study the flow quantitatively at the apex of the cylindrical surface. Three different driver pressures of 4, 8, and 12 bar were examined under maximum driver length (1477mm); the shock wave Mach number at the exit of the tube was 1.33, 1.52 and 1.67 respectively. Nomenclature a1 = speed of sound (m/s) in region one a2 = speed of sound (m/s) in region two a3 = speed of sound (m/s) in region there a4 = speed of sound (m/s) in region four M1 = incident Mach number M3 = Mach number in region three P1 = static pressure (bar) in region one P2 = static pressure (bar) in region two P3 = static pressure (bar) in region three P4 = static pressure (bar) in region four R = universal gas constant (J/kgK) t = time (ms) count from the rupture of the diaphragm t3 = time (ms) of the reflected rarefaction head meets the rarefaction tail tc = time (ms) when rarefaction head overtakes the contact surface