IMPACT ANALYSIS OF VARYING STRENGTH COUNTER-FLOW JET EJECTION ON A BLUNT SHAPED BODY IN A SUPERSONIC FLOW
Formation of a strong bow shock wave ahead of the blunt shaped body in a supersonic flow gives rise to rapid increase in temperature and pressure and reduction in velocity that causes substantial heat stress built up and may lead to structural damage of the body with disastrous consequences.At the University of New South Wales, the Aerodynamics Research Group has been exploring various methods of active flow control technologies for application to subsonic and supersonic flows. In this paper, the effects of deployment of counter- flow jet ejection as an active flow control method on the various flow field up stream of a blunt shaped body placed in a supersonic flow is examined. The concept of the counter-flow jet ejection relies on imparting sufficient momentum through its stagnation point to the flow field upstream of the body to cool the flow field around the body. An impact analysis of the effect of varying strength counter-flow jet ejection in terms of heat reduction and modification in terms of the temperature field is conducted. The blunt shaped body is represented by the configuration of the Apollo command module which is subjected to a free stream Mach number of 3 and the impact analysis is conducted using a transient two-dimensional numerical flow simulation of computational fluid dynamics. Results obtained are highly promising. It appears that substantial heat reduction on the body is possible using appropriate strength counter-flow jet. This finding may be of high practical significance and open up the possibility of developing a new thermal protective system using active flow control in reducing heat on a body in a supersonic flow and hence on a supersonic vehicle in flight.
heat dissipation, counter-flow jet ejection, minimum energy.