ANALYSIS OF PARTIALLY MIXED SUPERSONIC EJECTOR

This article presents an analytical model of a supersonic/subsonic, co nstant-area ejector whose exit how is not uniformly mixed, The primary and secondary streams, separated by the dividing streamline, are trea ted as quasi-one dimensional. The shear stress on the dividing streaml ine, the resulting heat transfer, and the wall stresses are applied ar tificially on the streams, Axisymmetric and two-dimensional configurat ions are considered. The model predicts that the axisymmetric ejector provides better thrust augmentation than the two-dimensional one, the latter suffering from higher skin-friction losses. Thrust increases wi th ejector length, but at a diminishing rate. For all configurations, thrust augmentation decreases with flight Mach number and becomes zero at a flight Mach number of about 0.7. Increasing the primary-to-secon dary area ratio has a minimal effect on thrust, The results compare fa vorably with available experimental data on pressure distributions and mass-flew ratios.