Flow and aeroacoustic attributes of highly-heated transitional rectangular supersonic jets
نویسندگان
چکیده
Heated transitional supersonic jets exhausting from a rectangular nozzle at over-expanded conditions are investigated by Large Eddy Simulations and Ffowcs-Williams Hawkings acoustic analogy. Four cases with fixed pressure ratio but different temperature ratios (TR) of 1.0, 2.0, 4.0, 7.0 analyzed. Numerical results show that the increasing jet velocity significantly increases, whereas its Reynolds number decreases about one order magnitude, which leads to 30% decrease in potential core length reduction shock cells. The temperatures also result shear layer convection Mach numbers consequently wave radiations fields. Pressure skewness kurtosis factors indicate crackle noise non-linear propagation effects high temperatures. For most heated TR 7.0, radiation is identified radiating 120 degrees, while large turbulence structure 150 degrees. Furthermore, vortex sheet model analysis LES data detect existence upstream-propagating neutral waves inside 7.0. observed screech frequency falls within range antisymmetric mode indicating highly-heated characterized an oscillation frequency.
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ژورنال
عنوان ژورنال: Aerospace Science and Technology
سال: 2021
ISSN: ['1626-3219', '1270-9638']
DOI: https://doi.org/10.1016/j.ast.2021.106747