Simulating Inlet Distortion Effects In A Direct-Connect Scramjet Combustor (Postprint)

摘要

Direct-connect simulations of scram jet combustors typically use facility nozzles designed to produce uniform flow entering the test article. Conversely, in free-jet and flight experiments, where air is ducted to the supersonic combustor through an inlet, flow entering the test article will be inherently distorted. These distortion effects can include non-uniform boundary layer thicknesses on the walls and relatively strong oblique shock waves. In this work, a special piece of hardware (called a distortion generator) was designed to mimic the effects of inlet distortion in a direct-connect test environment. The design methodology for this distortion generator will be described along with details of its fabrication and installation into the experimental research facility. Finally, the results of computational and experimental calibrations will be presented. These results confirm that distortion characteristics anticipated in freejet and flight experiments can be effectively simulated in the direct-connect test environment. This new hardware will enable future experimental investigations aimed at understanding the effects of inlet-induced distortion on combustor operability and performance.