Interaction of a Two-Dimensional Sonic Jet With a Supersonic Stream

Abstract

Experiments were conducted in a 1-in. × 3-in. supersonic wind tunnel on two-dimensional secondary fluid injection into a uniform primary supersonic stream. Both primary and secondary fluids were air at the same stagnation temperature, but the secondary stagnation pressure was varied from about 0.2 to 2 times the primary value; injection was sonic and the jet issued into the primary stream through a slit of constant width at 0 deg, 8 deg, 23 deg, and 50 deg upstream (the angle being measured from the normal to the primary flow). Primary stream Mach number covered the range from 1.64 to 2.96 in the tests. The shape of the leading shock shows similarity in modified blast variables at all angles of injection. It is also found that the separation shock in front of the main shock corresponds to a nearly constant flow deflection of about 10 deg. Estimates of the interaction force obtained from the measured pressure field show rough agreement with the calculations of Broadwell and of Spaid and Zukoski, and while supplementing the experimental data given by the latter, they bring out the dependence of the amplification factor on injection angle.