基于高阶空间精度格式和嵌套网格对旋翼尾迹捕捉的改进  

Rotor Wake Capture Improvement Based on High Order Spatially Accurate Schemes and Chimera Grids

作　　者：徐丽[1] 翁培奋[2] 

机构地区：[1]上海电力学院数理学院,上海200090 [2]上海大学上海市应用数学和力学研究所,上海200072

出　　处：《应用数学和力学》2011年第12期1461-1471,共11页Applied Mathematics and Mechanics

基　　金：国家自然科学基金资助项目(10802046)

摘　　要：发展了一种基于高阶迎风格式和嵌套网格捕捉直升机悬停旋翼涡尾迹的方法.无粘通量采用Roe Reimann求解器,使用改进的5阶加权基本无振荡(WENO)格式对交界面左右状态进行高阶插值,并与MUSCL插值进行比较.为便于捕捉尾迹和实施周期性边界条件,计算采用结构嵌套网格,其中高质量的旋翼网格完全嵌套于背景网格中.当解达到近似收敛后在桨尖涡分布区域对背景网格进行加密,如此经过3次得到优化的背景网格.考虑到WENO格式插值的特点,提出了搜索3层洞边界和人工外边界的方法以便插值的直接进行.用该方法对一跨音速和一亚音速悬停旋翼粘性流场进行了数值计算.数值结果表明:所发展方法对涡尾迹具有很高的捕捉能力;与MUSCL格式相比,WENO格式具有较低的数值耗散.A high-order upwind scheme was developed to capture vortex wake of a helicopter rotor in hover based on chimera grids.An improved fifth-order weighted essentially non-oscillatory（WENO） scheme was adopted to interpolate higher-order left and right states across a cell interface with the Roe Riemann solver updating inviscid flux,and was compared with the monotone upwind scheme for scalar conservation laws（MUSCL）.For profitably capturing the wake and enforcing period boundary condition,the computation regions of flows were discretized by using structured chimera grids composed of a fine rotor grid and a cylindrical background grid.In the background grid,the mesh cells located in the wake regions were refined after the solution reaches an approximate convergence.The optimized cylindrical mesh was attained by three remeshings.Considering the interpolation characteristic of WENO scheme,three layers of hole boundary and interpolation boundary were searched.The performance of the schemes was investigated in a transonic flow and a subsonic flow around hovering rotor.The results reveal that the present approach has the great capabilities to capture the vortex wake with high resolution,and WENO scheme has much lower numerical dissipation in comparison with MUSCL scheme.

关 键 词：悬停旋翼 涡尾迹 NAVIER-STOKES方程 WENO格式 嵌套网格 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]