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Applications of Turbulence Models in Simulation of Complex Flows
XIAO Zhi-xiang, LI Feng-wei, E Qin
2003, 20(4):
335-340.
Four turbulence models:algebraic Baldwin-Lomax model with Degani-Schiff modification, two versions of Johnson-King model (J-K90A and J-K92) and two-equation k-g model, are described and evaluated for missile supersonic flow, NASA TN D-712 standard model and the civil airplane wing-body configuration (two-block C-O mesh) transonic flows. The 3-D compressible Reynolds averaged Navier-Stokes (RANS) equations are integrated numerically by central-difference with artificial viscosity scheme, finite volume formulation and explicit multi-step Runge-Kutta algorithm. The turbulence equations of k-g model are explicitly solved in the same way as the RANS. Results show that all models can perform well for attached and mildly separated flows. For large angle-of-attack separated flow over the missile, k-g and J-K92 models match the experimental results much better than those with B-L and J-K90A models. According to the B-L model with some modification, the shock location logs behind those with the other three models for the civil airplane geometry. Model k-g, because of its advantages such as without using normal-to-wall distance, simple source terms and straightforward boundary conditions, performs best in the four models for complex configuration with multi-block mesh system or multi-wall interference. B-L and J-K models, despite of cheapness and robustness, both base on empirical Prandtl mixing-length hypothesis and need to calculate the distance normal to the wall, undoubtedly limiting the application scope of these models for multi-block mesh system and complex geometry.
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