Numerical Identification of Flow-Induced Oscillation Modes in Rectangular Cavities using URANS

Abstract

The present research focuses on flow oscillations in a planar rectangular cavity. The compressible URANS equations in combination with transition SST k−ω model are utilized to include the turbulence effects. The simulations are carried out for low Reynolds flow with Mach number ranging from 0.2 to 0.7. Flow features are investigated and the frequency analysis is discussed. Two flow oscillation modes, namely shear-layer mode and wake mode are thoroughly identified. The flow structure and oscillation frequencies compare well with LES and DNS results presented in the literature. Furthermore, the shear mode frequency is well aligned with that predicted by Rossiter. This research is aimed to evaluate the performance of URANS as an industrially attractive tool to capture flow phenomena, previously visualized by the aforementioned sophisticated methods.

Keywords

• urans; cavity flow; self induced oscillation; shear-layer mode; wake mode; mode detection.