Niladri Bose 473 days ago

Investigation of BRAHMOS-II missile with Forward-Facing Cavity at Mach 8 :

The blunt-nosed BRAHMOS-II hypersonic missile mounted with a forward-facing cavity is a good alternative to reduce the stagnation heating rates. The effects of a forward-facing cavity on heat transfer and aerodynamic coefficients have been investigated. Tests were carried out in hypersonic shock tunnel HST2, at a hypersonic Mach number of 8 using a 41 deg apex-angle blunt cone. The aerodynamic forces on the test model with and without a forward-facing cavity at various AoA (Angles of Attack) are measured by using an internally mountable accelerometer force balance system. Heat flux measurements have been carried out on the test model with and without a forward-facing cavity of the entire surface at zero degree angle of attack with platinum sensors. A numerical simulation was also carried out using the computational fluid dynamics code (CFX-Ansys 5.7). An important result of this study is that the smaller cavity diameter has the highest lift-to-drag ratio, whereas the medium cavity has the highest heat flux reduction. The shock structure around the test model has also been visualized using the SCHLIEREN flow visualization technique. The visualized shock structure and the measured aerodynamic forces on the missile-shaped body with cavity configurations agree well with the axisymmetric numerical simulations.

The structure of the hypersonic flow over a cavity has been studied experimentally & numerically