Design and analysis of breathing blunt nose (BBN) with flat-faced aero-disk for drag reduction in supersonic flows.

The design of a vehicle flying at supersonic and hypersonic velocities plays a crucial role in the performance and efficiency of the vehicle, because at these velocities there will be shock waves dominating the flow. If the vehicle is designed in such a way that its deflection angle is less than the maximum deflection angle, then the shock wave will be attached to nose of body, which increases the heat load on the vehicle. Therefore, the vehicles, which fly at these speeds, are designed in such a way that a better thermal management is achieved. To satisfy this requirement, the vehicle's body is designed as blunt body, which will have the defection angle greater than its maximum deflection angle so that the shock wave will be a detached one and it will not be in contact with the body. This reduces the heat load on the body and better thermal management is achieved. Though better thermal management is achieved with the blunt body, the drag experienced by the body will increase, as detached shock wave acts like a cushion between the body and the air stream. In order to reduce the fuel consumption and to achieve greater efficiency, the drag has to be reduced. In this work a Breathing Blunt Nose along with aflat-faced aero-disk is considered for study and investigations are done varying angles of attack and the resulting drag, lift and heat flux have been measured. Due to the relief offered because of breathing of high pressure flow and flow being ejected in the base region, the shock wave will become weaker. In the present study, a Breathing Blunt Nose with a Flat-faced Aero-Disk(BBN-AD) and a Simple Blunt Body with Flat-faced Aero-Disk(SBN-AD) are considered and a comparison has been made. Flow field around the body has been visualized by streamline contours. [ABSTRACT FROM AUTHOR]