A two-step radial basis function-based CFD mesh displacement tool

Abstract Mesh displacement based on Radial Basis Functions (RBF) interpolation is known for its ability to preserve the validity and quality of the mesh, even for large displacements, without being affected by mesh connectivity. However, in the case of large meshes, such as those used in real-world Computational Fluid Dynamics (CFD) applications, RBF interpolation, in its standard formulation, becomes excessively expensive. This paper proposes a cost reduction technique for mesh displacement based on RBF, by splitting the process into two steps. In the first step, named predictor, a data reduction algorithm that adaptively agglomerates mesh boundary nodes by reducing the RBF interpolation problem size is used. Upon completion of the first step, due to the agglomeration and the fact that the RBF interpolation is applied to the boundary nodes too, the so-displaced boundaries do not match the given displacements; thus, the position of the boundary nodes must be corrected during the second step, named corrector. The latter performs a local deformation based on RBF kernels with local support, to make the boundary conform to the known displacements of its nodes. The proposed method is accelerated by employing the Sparse Approximate Inverse preconditioner based on geometrical considerations and the Fast Multipole Method. The method and the programmed software are validated on three test cases related to the deformation of CFD meshes inside a duct and a turbine stator row as well as around a car model.

[1]  Marco Evangelos Biancolini,et al.  Sails trim optimisation using CFD and RBF mesh morphing , 2014 .

[2]  M. Floater,et al.  Multistep scattered data interpolation using compactly supported radial basis functions , 1996 .

[3]  Gregory E. Fasshauer,et al.  Meshfree Approximation Methods with Matlab , 2007, Interdisciplinary Mathematical Sciences.

[4]  M. Benzi Preconditioning techniques for large linear systems: a survey , 2002 .

[5]  Eric Darve,et al.  The black-box fast multipole method , 2009, J. Comput. Phys..

[6]  Christian B. Allen,et al.  Efficient and exact mesh deformation using multiscale RBF interpolation , 2017, J. Comput. Phys..

[7]  Gene H. Golub,et al.  Matrix computations , 1983 .

[8]  F. J. Narcowich,et al.  Multilevel Interpolation and Approximation , 1999 .

[9]  Holger Wendland,et al.  Piecewise polynomial, positive definite and compactly supported radial functions of minimal degree , 1995, Adv. Comput. Math..

[10]  S. Porziani,et al.  Aerodynamic Optimization of Car Shapes Using the Continuous Adjoint Method and an RBF Morpher , 2018, Computational Methods in Applied Sciences.

[11]  Stefan Menzel,et al.  RBF morphing techniques for simulation-based design optimization , 2014, Engineering with Computers.

[12]  Tayfun E. Tezduyar,et al.  Automatic mesh update with the solid-extension mesh moving technique , 2004 .

[13]  L. Montefusco,et al.  Radial basis functions for the multivariate interpolation of large scattered data sets , 2002 .

[14]  Giorgos A. Strofylas,et al.  An agglomeration strategy for accelerating RBF-based mesh deformation , 2017, Adv. Eng. Softw..

[15]  Kyriakos C. Giannakoglou,et al.  Unsteady CFD computations using vertex‐centered finite volumes for unstructured grids on Graphics Processing Units , 2011 .

[16]  Zhufeng Yue,et al.  Review: Layered elastic solid method for the generation of unstructured dynamic mesh , 2010 .

[17]  William F. Moss,et al.  Decay rates for inverses of band matrices , 1984 .

[18]  Charbel Farhat,et al.  A three-dimensional torsional spring analogy method for unstructured dynamic meshes , 2002 .

[19]  Bruno Carpentieri,et al.  Sparse pattern selection strategies for robust Frobenius-norm minimization preconditioners in electromagnetism , 2000, Numer. Linear Algebra Appl..

[20]  Eusebio Valero Sánchez,et al.  An interpolation tool for aerodynamic mesh deformation problems based on octree decomposition , 2012 .

[21]  H. Bijl,et al.  Mesh deformation based on radial basis function interpolation , 2007 .

[22]  Martin D. Buhmann,et al.  Radial Basis Functions: Theory and Implementations: Preface , 2003 .

[23]  Matthew L. Staten,et al.  A Comparison of Mesh Morphing Methods for 3D Shape Optimization , 2011, IMR.

[24]  Bruno Carpentieri,et al.  Sparse symmetric preconditioners for dense linear systems in electromagnetism , 2004, Numer. Linear Algebra Appl..

[25]  Yong Zhao,et al.  A general method for simulation of fluid flows with moving and compliant boundaries on unstructured grids , 2003 .

[26]  Bruno Carpentieri,et al.  Combining Fast Multipole Techniques and an Approximate Inverse Preconditioner for Large Electromagnetism Calculations , 2005, SIAM J. Sci. Comput..

[27]  Leif Kobbelt,et al.  Real‐Time Shape Editing using Radial Basis Functions , 2005, Comput. Graph. Forum.

[28]  Christian B Allen,et al.  Parallel efficient mesh motion using radial basis functions with application to multi-bladed rotors , 2008 .

[29]  Guillaume Alléon,et al.  Sparse approximate inverse preconditioning for dense linear systems arising in computational electromagnetics , 1997, Numerical Algorithms.

[30]  Roy Koomullil,et al.  Mesh Deformation Approaches A Survey , 2016 .

[31]  L. Greengard,et al.  Regular Article: A Fast Adaptive Multipole Algorithm in Three Dimensions , 1999 .

[32]  H. Tsai,et al.  Unsteady Flow Calculations with a Parallel Multiblock Moving Mesh Algorithm , 2001 .

[33]  Christian B Allen,et al.  Parallel universal approach to mesh motion and application to rotors in forward flight , 2007 .

[34]  Kyriakos C. Giannakoglou,et al.  SHAPE OPTIMIZATION OF TURBOMACHINERY ROWS USING A PARAMETRIC BLADE MODELLER AND THE CONTINUOUS ADJOINT METHOD RUNNING ON GPUS , 2016 .

[35]  M. Benzi,et al.  A comparative study of sparse approximate inverse preconditioners , 1999 .

[36]  Hester Bijl,et al.  Adaptive radial basis function mesh deformation using data reduction , 2016, J. Comput. Phys..

[37]  Leslie Greengard,et al.  A fast algorithm for particle simulations , 1987 .

[38]  Emmanuel Agullo,et al.  Task-Based FMM for Multicore Architectures , 2014, SIAM J. Sci. Comput..

[39]  A. Kallischko Modified Sparse Approximate Inverses (MSPAI) for Parallel Preconditioning , 2008 .

[40]  Brian T. Helenbrook,et al.  Mesh deformation using the biharmonic operator , 2003 .

[41]  Juanmian Lei,et al.  Radial basis function mesh deformation based on dynamic control points , 2017 .

[42]  Chau-Lyan Chang,et al.  Mesh deformation based on fully stressed design: the method and 2‐D examples , 2007 .

[43]  Ning Qin,et al.  Fast dynamic grid deformation based on Delaunay graph mapping , 2006 .

[44]  Clarence O. E. Burg,et al.  Analytic study of 2D and 3D grid motion using modified Laplacian , 2006 .

[45]  Christian B. Allen,et al.  Reduced surface point selection options for efficient mesh deformation using radial basis functions , 2010, J. Comput. Phys..

[46]  J. Batina Unsteady Euler airfoil solutions using unstructured dynamic meshes , 1989 .

[47]  Bruno Carpentieri,et al.  Algebraic preconditioners for the Fast Multipole Method in electromagnetic scattering analysis from large structures: trends and problems , 2009 .

[48]  Joe F. Thompson,et al.  Numerical grid generation: Foundations and applications , 1985 .

[49]  Jussi Rahola,et al.  Experiments On Iterative Methods And The Fast Multipole Method In Electromagnetic Scattering Calcula , 1998 .

[50]  C. R. Ethier,et al.  A semi-torsional spring analogy model for updating unstructured meshes in 3D moving domains , 2005 .

[51]  Carlo L. Bottasso,et al.  The ball-vertex method: a new simple spring analogy method for unstructured dynamic meshes , 2005 .

[52]  Jeroen A. S. Witteveen,et al.  Explicit and Robust Inverse Distance Weighting Mesh Deformation for CFD , 2010 .

[53]  Nikolaus A. Adams,et al.  Introduction of a New Realistic Generic Car Model for Aerodynamic Investigations , 2012 .

[54]  Ramani Duraiswami,et al.  Fast Radial Basis Function Interpolation via Preconditioned Krylov Iteration , 2007, SIAM J. Sci. Comput..