Study of Total Pressure Losses at the Engine Face of a Submerged Inlet with an Ingested Vortex

Abstract

An experimental study of the effect of an ingested vortex into an S-duct diffuser on flow conditions at the engine face is presented. In order to form a boundary layer of well-defined thickness ahead of the intake which is also in-gested at the same time, the diffuser is arranged on a flat plate. The dependence of the vortex circulation on the flow in the diffuser has been examined in a paramet-ric study in a blow-down wind tunnel. The free-stream Mach number was varied between M = 0.30 and M = 0.65 at a fixed mass flow at the engine face. In the in-troduction the importance of boundary layer ingesting highly integrated intakes is briefly discussed. This is followed by a description of the analytical design of the generic intake model, the cryogenic blowdown tunnel DNW-KRG in which the experimental tests have been performed, and the measurement techniques. There-after, experimental findings are discussed in detail and conclusions are drawn.