Anke Kovar

Comparison of experimental and numerical investigation on a jet in a supersonic cross-flow

Flow interaction of three different jet configurations ejecting air from a flat plate into a supersonic cross flow were investigated experimentally and numerically. The test conditions encompassed a jet pressure ratio of P 0j , P ∞ = 100 at a Mach number of M ∞ = 5 and Reynolds number of about Re ∞ = 25 x 10 6 based on the length of the flat plate. The investigated test cases are: a) single jet; b) four jets positioned in-line in main flow direction; c) four jets positioned side-by-side in spanwise direction. The prediction of the overall flow phenomena as occurring within the interaction area was in fair agreement with the experiments, although quantitatively differences occur that will be discussed in the paper. The results of the comparison are presented and the experimental data are used to validate the applied code.

Study of Supersonic Flow Separation Induced by a Side Jet and its Control

In this basic study the interaction of a lateral jet with supersonic external flow was examined. The study consists of wind tunnel experiments at Mach 5 in the Ludwieg Tube Facility of the German Aerospace Center (DLR) as well as of numerical simulations with the DLR-TAU-code. The efficiency of two flow control devices (upstream mounted needle and weak jet) for stabilization and control of flow separation by means of bow shock attenuation was investigated. The results show that the investigated flow control devices are able to influence the shape and size of the main separation zone but are not capable to suppress it completely. A comparison of wall pressures and limiting streamline patterns showed reasonable agreement between numerical simulations and experimental data.