Shock wave configurations and flow structures in non-axisymmetric underexpanded sonic jets

摘要: An experimental and numerical study of underexpanded free sonic jet flows issuing from rectangular, elliptical slot nozzles has been undertaken. Aspect ratios (AR) 1, 2, 4 are described at pressure (exit plane to ambient pressure), 2 3. There is good qualitative agreement between the observations predictions. In case rectangular jets, a complex system shock waves forming incident identified. This wave originates corners nozzle exits, proceeds downstream. Mach reflections found occur on surface as well presence disk terminating first cell. shape square, hexagon, or an octagon depending shape. For formation was not observed along minor axis for AR > 2. The originate downstream exit in major plane. undergoes transition reflection it propagates exit. all cases tested, boundary significantly distorted. narrowing diagonal observed, jets switching noted.