| タイトル | Computation of Separated and Unsteady Flows with One- and Two-Equation Turbulence Models |
| 本文（外部サイト） | http://hdl.handle.net/2060/19970001720 |
| 著者（英） | Menter, Florian R.; Ekaterinaris, John A. |
| 著者所属（英） | NASA Ames Research Center |
| 発行日 | 1994-01-01
1994 |
| 言語 | eng |
| 内容記述 | The ability of one- and two-equation turbulence models to predict unsteady separated flows over airfoils is evaluated. An implicit, factorized, upwind-biased numerical scheme is used for the integration of the compressible, Reynolds averaged Navier-Stokes equations. The turbulent eddy viscosity is obtained from the computed mean flowfield by integration of the turbulent field equations. The two-equation turbulence models are discretized in space with an upwind-biased, second order accurate total variation diminishing scheme. One and two-equation turbulence models are first tested for a separated airfoil flow at fixed angle of incidence. The same models are then applied to compute the unsteady flowfields about airfoils undergoing oscillatory motion at low subsonic Mach numbers. Experimental cases where the flow has been tripped at the leading edge and where natural transition was allowed to occur naturally are considered. The more recently developed field-equation turbulence models capture the physics of unsteady separated flow significantly better than the standard kappa-epsilon and kappa-omega models. However, certain differences in the hysteresis effects are obtained. For an untripped high-Reynolds-number flow, it was found necessary to take into account the leading edge transitional flow region in order to capture the correct physical mechanism that leads to dynamic stall. |
| NASA分類 | Fluid Mechanics and Heat Transfer |
| レポートNO | 97N11494
NASA-TM-111799
NAS 1.15:111799
AIAA Paper 94-0190 |
| 権利 | Copyright, Distribution as joint owner in the copyright |
