TY - CONF
T1 - Numerical investigation of the flow past a cavity
AU - Colonius, Tim
AU - Basu, Amit J.
AU - Rowley, Clarence W.
N1 - Funding Information:
This paper is partly based on two research projects funded by the Federal Ministry of Economics and Energy (BMWi), the Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB) and the Federal Agency for Energy Efficiency (BfEE), in Germany. We would like to thank the representatives from these federal institutions for the fruitful discussions during the work on these projects. We are also grateful to the editors of the special issue and three anonymous reviewers of this paper for their constructive and helpful comments and suggestions.
Publisher Copyright:
© 1999 by the authors. Published by the American Institute of Aeronautics and Astronautics, Inc.
PY - 1999
Y1 - 1999
N2 - Numerical simulations are used to investigate the resonant instabilities in the flow past an open cavity. The compressible Navier-Stokes equations are solved directly (no turbulence model) for two-dimensional cavities with laminar boundary layers upstream. The computational domain is large enough to directly resolve a portion of the radiated acoustic field. The results show a transition from a shear layer mode, for shorter cavities and lower Mach numbers, to a wake mode for longer cavities and higher Mach numbers. The shear layer mode is well characterized by Rossiter modes. The wake mode is characterized instead by a large-scale vortex shedding with Strouhal number independent of the Mach number. The vortex shedding causes the boundary layer to periodically separate upstream of the cavity. The wake mode oscillation is similar to that reported by Gharib and Roshko (J. Fluid Mech., 177, 1987) for incompressible flow with a laminar upstream boundary layer. The results suggest that laminar separation upstream of the cavity edge is the cause of the transition to wake mode.
AB - Numerical simulations are used to investigate the resonant instabilities in the flow past an open cavity. The compressible Navier-Stokes equations are solved directly (no turbulence model) for two-dimensional cavities with laminar boundary layers upstream. The computational domain is large enough to directly resolve a portion of the radiated acoustic field. The results show a transition from a shear layer mode, for shorter cavities and lower Mach numbers, to a wake mode for longer cavities and higher Mach numbers. The shear layer mode is well characterized by Rossiter modes. The wake mode is characterized instead by a large-scale vortex shedding with Strouhal number independent of the Mach number. The vortex shedding causes the boundary layer to periodically separate upstream of the cavity. The wake mode oscillation is similar to that reported by Gharib and Roshko (J. Fluid Mech., 177, 1987) for incompressible flow with a laminar upstream boundary layer. The results suggest that laminar separation upstream of the cavity edge is the cause of the transition to wake mode.
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M3 - Paper
AN - SCOPUS:84982318235
T2 - Aeroacoustics Conference and Exhibit, AIAA/CEAS 1999
Y2 - 10 May 1999 through 12 May 1999
ER -