Unsteady Pressure Measurements with PSP

Abstract

The mixing fields within a scram-jet combustion chamber are visualized using pressure sensitive paint (PSP) as an oxygen sensor. The experiments are performed in a small supersonic wind tunnel at the National Aerospace laboratory - Kakuda Research Center (NAL-KRC). The main stream mach number is 2.4, and the dynamic pressure ratio between the injected gas and the main flow are 0.3, 0.7, 1.1 and 1.5. Three fuel injection nozzles are used; air and O₂ is injected from these nozzles. The results show that the jet has its own independent flow structure, and that little mixing of gas occurs between the flow structures created by each nozzle.