Hypersonic jet control effectiveness

Abstract.

The present study aims to identify some of the parameters which determine the upstream extent and the lateral spreading of the separation front around an under-expanded transverse jet on a slender blunted cone. The tests were conducted in the Cranfield hypersonic facility at $M_\infty = 8.2$, $Re_\infty /{\rm cm} = 4.5$ to $9.0 \times 10^4$ and at $M_\infty = 12.3$, $Re_\infty /{\rm cm} = 3.3 \times 10^4$. Air was used as the working gas for both the freestream and the jet. Schlieren pictures were used for the visualisation of the three-dimensional structures around the jet. Pressure, normal force and pitching moment measurements were conducted to quantitatively study the interaction region and its effects on the vehicle. An analytical algorithm has been developed to predict the shape of the separation front around the body.