VORTEX-GENERATOR INSTALLATION STUDIES ON STEADY-STATE AND DYNAMIC DISTORTION

The theoretical and experimental work carried out under the NASA/MOD j oint aeronautical program has shown that computational fluid dynamics (CFD) vortex-generator installation designs successfully managed inlet -duct now distortion and that significant benefits in now unsteadiness at the engine face were also present. The main conclusions to date fr om the collaborative effort between the NASA Lewis Research Center and the Defence Research Agency in Bedford are as follows: 1) Vortex-gene rator installations can be designed to be effective over a wide-range of inlet operating conditions using CFD and formal optimization proced ures, 2) reductions in steady-state engine face distortion of up to 80 % have been measured in the M2129 inlet S-duct using CFD-designed vort ex-generator installations, 3) reductions in flow unsteadiness of up t o 80% have been measured in the M2129 inlet S-duct using CFD-designed vortex-generator installations, and 4) the reduced Navier-Stokes code RNS3D is a useful tool to design vortex-generator installations to man age engine-face distortions over a wide range of inlet operating condi tions.