NACA4412翼型低速绕流的定常／非定常计算对比研究

摘要

Numerical simulation of NACA4412 airfoil around flow is implemented based on steady and unsteady computational methods .Convection terms and diffusion terms are calculated using Roe scheme and center difference scheme respectively .The dual-time stepping method with implicit approximate-factorization employed in time marc-hing.Two equation SST k-ωturbulence model is forfeited for steady/unsteady computations .Computational results of steady/unsteady numerical simulations are compared with experimental data .Periodic vortex shedding behind airfoil tail is obtained using unsteady numerical simulation .Time-averaged computational results obtained by un-steady method are batter then steady computational results .%对NACA4412翼型低速绕流进行了定常／非定常数值计算。对流项及扩散项的空间离散分别采用Roe格式和二阶中心格式，时间方向采用了二阶精度的双时间步隐式方法求解，湍流模式采用了两方程SST k-ω模式。将定常／非定常数值计算结果与实验数据进行了对比，非定常计算显示出了翼型尾缘附近周期性脱落涡现象，尾迹流动区里非定常流动现象明显，时间平均的非定常计算结果与实验数据符合的更好。