Abstract

Two dimensional numerical simulations were conducted to investigate the supersonic flow around tandem cavities with front wall inclinations in both cavities and alternately inclining the front wall of each cavity at 90° and 120°. The unsteady simulations of the four models were conducted in ANSYS WORKBENCH using Reynolds Averaged Navier Stokes (RANS) equation with the k-ω turbulence model. Open cavities were considered with aspect ratio of the first cavity 3 and the second cavity 1. The Mach number was taken as 2 and Reynolds number as 4.5 x 105 . The cavities are characterised by unsteady flow due to the formation of vortices caused by shear layer interaction with cavity internal flow and formation of oblique shocks and expansion shocks. From the study it is observed that aft cavity flow behaviour is dependent on the fore cavity’s geometry. It is also observed that slightly different flow behaviour is also observed at the rear wall of fore cavity based on the aft cavity’s geometry. Introducing inclination in the wall of the cavities, reduces the peak pressure value at rear wall of the fore cavity but increases unsteadiness. A comparison of pressure oscillations and dominant frequencies has been studied for the models considered.

Keywords

References

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