Subsonic and Transonic Jet Control with Cross-Wire

Abstract

Cross-wire eectiv eness for subsonic and sonic jet control is reported in this paper. Mach 0.4, 0.6, 0.8 and 1.0 axisymmetric jets from a convergent nozzle with cross-wire along a diameter at the exit were studied. The cross-wire was found to be eectiv e in promoting jet mixing right from the nozzle exit, at all Mach numbers. For the underexpanded sonic jet at NPR 3, 5 and 7, the cross-wire inuenced the core and the shock cells, causing signican t reduction of core length and weakening of the shocks at all levels of underexpansion. The jets from the nozzle with cross-wire spread faster in the direction normal to the cross-wire.