Rotor Wake Capture Improvement Based on High Order Spatially Accurate Schemes and Chimera Grids
-
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.
-
关键词:
- 悬停旋翼 /
- 涡尾迹 /
- Navier-Stokes方程 /
- WENO格式 /
- 嵌套网格
Abstract: 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.-
Key words:
- hovering rotor /
- vortex wake /
- Navier-Stokes equations /
- WENO scheme /
- chimera grids
-
[1] Egolf T. Recent rotor wake simulation and modeling studies at United Technologies Corporation[R]. AIAA paper 2000-115, 2000. [2] He C, Zhao J. Modeling rotor wake dynamics with viscous vortex particle method[J]. AIAA Journal, 2009, 47(4): 902-915. doi: 10.2514/1.36466 [3] Harris R E, Sheta E F, Habchi S D. An efficient adaptive Cartesian vorticity transport solver for rotorcraft flowfield analysis[R]. AIAA paper 2010-1072, 2010. [4] Wagner S. On the numerical prediction of rotor wakes using linear and non-linear methods[R]. AIAA paper 2000-0111, 2000. [5] Dietz M, Keler M, Kramer E, Wagner S. Tip vortex conservation on a helicopter main rotor using vortex-adapted chimera grids[J]. AIAA Journal, 2007, 45(8): 2062-2074. doi: 10.2514/1.28643 [6] Caradonna F X, Directorate A, Aviation U S, Command M. Developments and challenges in rotorcraft aerodynamics[R]. AIAA paper 2000-0109, 2000. [7] Hariharan N, Sankar L N. High-order essentially nonoscillatory schemes for rotary-wing wake computations[J]. Journal of Aircraft, 2004, 41(2): 258-267. doi: 10.2514/1.9320 [8] Hariharan N. High order accurate numerical convection of vortices across overset interfaces[R]. AIAA paper 2005-1263, 2005. [9] Usta E, Wake B E, Egolf T A, Sankar L N. Application of a symmetric total variation diminishing scheme to aerodynamics and aeroacoustics of rotors[C]Presented at the American Helicopter Society 57th Annual Forum. Washington D C, May 9-11, 2001. [10] Kim H, Williams M, Lyrintzis A. Improved method for rotor wake capturing[J]. Journal of Aircraft, 2002, 39(5): 794-803. doi: 10.2514/2.3025 [11] Borges R, Carmona M, Costa B, Don W S. An improved weighted essentially non-oscillatory scheme for hyperbolic conservation laws[J]. Journal of Computational Physics, 2008, 227(6): 3191-3211. doi: 10.1016/j.jcp.2007.11.038 [12] Liu X D, Osher S, Chan T. Weighted essentially non-oscillatory schemes[J]. Journal of Computational Physics, 1994, 115(1): 200-212. doi: 10.1006/jcph.1994.1187 [13] Jiang G S, Shu C W. Efficient implementation of weighted ENO schemes[J]. Journal of Computational Physics, 1996, 126(1): 202-228. doi: 10.1006/jcph.1996.0130 [14] Yoon S, Jameson A. Lower-upper symmetric Gauss-Seidel method for the Euler and Navier-Stokes equations[J]. AIAA Journal, 1998, 26(9): 1025-1026. [15] Chen R, Wang Z. Fast, block lower-upper symmetric Gauss-Seidel scheme for arbitrary grids[J]. AIAA Journal, 2000, 38(12): 2238-2245. doi: 10.2514/2.914 [16] Baldwin B S, Lomax H. Thin layer approximation and algebraic model for separated turbulent flow[R]. AIAA paper 78-0257, 1978. [17] Roe P L. Approximate Riemann solvers, parameter vectors, and difference schemes[J]. Journal of Computational Physics, 1981, 43(2): 357-372. doi: 10.1016/0021-9991(81)90128-5 [18] Chen X, Zha G C, Yang M T. Numerical simulation of 3-D wing flutter with fully coupled fluidstructural interaction[J]. Computers and Fluids, 2007, 36(5): 856-867. doi: 10.1016/j.compfluid.2006.08.005 [19] Harten A. High resolution schemes for hyperbolic conservation laws[J]. Journal of Computational Physics, 1983, 49(3): 357-393. doi: 10.1016/0021-9991(83)90136-5 [20] Xu L, Yang A M, Guang P, Weng P F. Numerical experiments using one high-resolution scheme for unsteady inviscid compressible flows[J]. Acta Aerodynamica Sinica, 2009, 27(5): 602-607. [21] Titarev V A, Toro E F. WENO schemes based on upwind and centred TVD fluxes[J]. Computers and Fluids, 2005, 34(6): 705-720. doi: 10.1016/j.compfluid.2004.05.009 [22] Caradonna F X, Tung C. Experimental and analytical studies of a model helicopter rotor in hover[R]. NASA TM 81232, 1981. [23] Strawn R C, Barth T J. A finite-volume Euler solver for computing rotary-wing aerodynamics on unstructured meshes[J]. Journal of the American Helicopter Society, 1993, 38: 61-67. doi: 10.4050/JAHS.38.61
点击查看大图
计量
- 文章访问数: 1312
- HTML全文浏览量: 85
- PDF下载量: 728
- 被引次数: 0