Supersonic flow from an aspect ratio 7.65 rectangular nozzle is simulated at ideally expanded operating condition. The aim of the current work is to understand the effect of the high aspect ratio on the farfield acoustics and the features of the jet plume that might create directional dependence for the noise. Validation of the acoustic data for the rectangular nozzle is performed against experimentally recorded sound pressure level (SPL) spectra for a host of observer locations around the asymmetric nozzle. Results of the integrated overall sound levels show deviation from the experimental data in the peak noise direction as well as at upstream angles. The simulated results show a higher average core flow streamwise velocity than expected at ideally expanded conditions and that increases the power level of the noise sources. However comparison of time averaged nearfield data agrees well with experiments in location of shock cells and expansion of the shear layers. Other flow field features are examined and they offer an acoustic baseline for future noise reduction efforts for high aspect ratio rectangular nozzle geotnetries that are informed from the insights developed through the current work.
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