SMALL DISTURBANCE NAVIER-STOKES COMPUTATIONS EMPLOYING THE WILCOX K-OMEGA TURBULENCE MODEL

摘要

Developed at Technische Universit?t München,rnthe small disturbance Navier-Stokes methodrnFLM-SD.NS has been substantiated as both anrnefu0002cient and accurate means for providing unsteadyrnair loads to the transonic aeroelastic analysisrnprocess. In an effort to extend its rangernof applicability, a dynamically linear instancernof the Willcox k-w eddy-viscosity closure is incorporated,rncomplementing the original Spalart-rnAllmaras option. Harmonic pitching oscillationsrnof a generic high-aspect-ratio wing are investigated.rnFor the attached-u0003ow cases, the k-w incarnationrnof FLM-SD.NS delivers equally accuraternpredictions as the Spalart-Allmaras original.rnReductions in computation time, up to halfrnan order of magnitude, in relation to the comparativerntime-domain Reynolds-averaged Navier-rnStokes method FLM-NS are again observed. Forrnthe detached-u0003ow case, the primary beneu0002t ofrnthe Wilcox k-w eddy-viscosity closure is witnessedrnin the FLM-NS-supplied time-invariantrnmean solution about which FLM-SD.NS computesrnthe dynamically linear perturbation: At localitiesrnof u0003ow detachment, the supersonic-u0003owterminatingrnshock is rendered distinctly closerrnto the measured physical position than for thernSpalart-Allmaras instance. Limitations of thernsmall disturbance approach, however, becomernapparent for both incarnations, as a substantialrndegree of nonlinear interaction physically exists.