Time- and Space-Dependence of Particulate Effluent in the Exhaust Plume of a Pulsed Liquid Bipropellant Engine

Abstract : The temporal and radial profiles of particulate mean sizes and densities in the exhaust plume of a pulsed 5-lbf thrust liquid bipropellant rocket engine have been determined. The primary goal of this analysis has been to establish the capability of simulating the characteristics of multi-second firings at high altitude. The results demonstrate that steady-state particle formulation kinetics are achieved in times on the order of 10 milliseconds. Further, combustion instability was shown to be unimportant for combustion chamber length-to-diameter ratios less than 30. The particle size and flux measurements reported here additionally demonstrate the utility of Mie scattering techniques for pulsed engine testing and contamination tests.