DLR-F6/FX2B翼身组合体构型高阶精度数值模拟

High-order accuracy numerical simulation of DLR-F6/FX2B wing-body configuration

基于雷诺平均Navier-Stokes(RANS)方程和结构网格技术,采用五阶空间离散精度的加权紧致非线性格式(WCNS)和剪切应力输运(SST)两方程湍流模型,开展了DLR-F6和DLR-F6_FX2B2种翼身组合体构型的高阶精度数值模拟,计算外形来自AIAA第三届阻力预测研讨会。主要目的是确认WCNS模拟跨声速典型运输机构型和预测局部构型变化引起的气动特性变化量的能力。在固定升力系数条件下,采用粗、中、细3套网格开展了网格收敛性研究,从气动力系数、压力系数分布、表面流态等方面研究了网格规模对DLR-F6和DLR-F6_FX2B翼身组合体数值模拟结果的影响;采用中等网格开展了来流迎角对2种翼身组合体气动特性的影响研究。通过与National Transonic Facility(NTF)的试验结果和CFL3D的计算结果对比,表明采用高阶精度计算方法得到了网格收敛的数值模拟结果,较好地模拟了DLR-F6翼身组合体局部修型引起的微小气动特性变化和翼身结合部流动特性的差异。

Based on the Reynolds-averaged Navier-Stokes （RANS） equations and structured grid technology, the fifth-order weighted compact nonlinear scheme （WCNS） and shear stress transport （SST） turbulence model are adopted to simulate DLR-F6 wing-body and FX2B fairing configuration from the third AIAA CFD drag prediction workshop. The main purpose of the present work is to further validate the ability of WCNS in the simulation of transonic problems and the prediction of aero- dynamic characteristic variation due to tiny variation of the configuration. The grid convergence study is performed with coarse, medium and fine grid systems at fixed lift coefficient, and the effects of grid density on the simulation of DLR-F6 with and without FX2B fairing are studied from the aspects of aerodynamic coefficients, pressure distribution and flow pattern on the surface. The variations of aerodynamic characteristics with angles of attack are performed with the medium grid system. Compared to the experimental data from the National Transonic Facility （NTF）and CFL3D numerical results, the numerical simulation indicate that grid convergence results are obtained with the high-order numerical method; the small incremental aerodynamic characteristics and the local flow difference at the wing-body junction with and without FX2B fairing can be pre- dicted reasonably.