T. Hiraiwa et al., PERFORMANCE VARIATION OF SCRAMJET NOZZLE AT VARIOUS NOZZLE PRESSURE RATIOS, Journal of propulsion and power, 11(3), 1995, pp. 403-408
An experimental study of scramjet nozzle was conducted to investigate
how the nozzle now is affected by ambient pressure. In order to elucid
ate the aerodynamic properties of nozzle flow, detailed measurements o
f thrust and wall pressure were carried out using cold nitrogen. Nozzl
e now was also visualized using a shear sensitive liquid crystal. Wall
pressure and shear stress distributions in an overexpanded nozzle sho
wed that nozzle flow includes a crossing shock wave made at the side-f
ences. This flowfield can be approximated as a supersonic inlet now co
mpressed by sidewalls. The high-pressure region on the nozzle ramp gen
erated by the shock waves results in a higher performance in scramjet
nozzle than that estimated for a two-dimensional separation from the r
amp.