Numerical investigations of supersonic base flows using DES

The Detached Eddy Simulation (DES) method is used to study a supersonic base flow. The flow is along a cylinder axis and separates suddenly at the blunt base corner. Cases with and without a central bleed jet at the base are considered. The Mach number is 2.46 and the (unit) Reynolds number is approximately 50 million per meter. Computed turbulence statistics in the wake region of the flow are compared with experimental results. The agreement with experiments is found to be good for the no bleed case. A time-series analysis of computed base pressure fluctuations is performed and compared with the experimental data of Janssen & Dutton (2004). The agreement with experiment for these statistics is only qualitatively acceptable. The case with a central bleed jet is also examined. It is found that the results from this case diverge from the experimental values to a large extent.