Experimental investigation of the pulsing flow field around four types of spiked-blunt body at Mach 2.2

Abstract

In this paper, unsteady flow pulsation over four types of spiked-blunt body model and related pulsation suppression methods are investigated through wind tunnel experiments. Direct-connect wind tunnel is used to provide supersonic incoming flow of Ma 2.2 and a classic pointed spike and three types of aerodome spike are tested at zero/non-zero angle of attack. High-speed schlieren and dynamic pressure sensors are used to capture the dynamic evolution of unsteady flow field around the spikes. Then the measurement results with high spatial-temporal resolution are processed with three statistical methods. Results indicate that the aerodome spike can effectively suppress the flow pulsation both at zero/non-zero angle of attack. The suppression effect of standard/double aerodome and inverse aerodome can reach 60.9% and 47.3%, respectively. By using the aerodome, the pulsation mode can be transformed into a special state between oscillation mode and pulsation mode, named ‘suppressed pulsation mode’. In the suppressed pulsation mode, the original large-scale motion of shock wave system is decomposed into a stable foreshock and a slightly unsteady aftershock with small-scale periodic movement. The statistical results further reveal that the unsteady motion of afterbody shock is closely related to the stability of the recirculation zone and the key to suppress the flow pulsation is to create a stable recirculation zone ahead the blunt body.