Acceleration of unsteady vortex lattice method via dipole panel fast multipole method

作     者：Shuai DENG Chen JIANG Yunjie WANG Haowen WANG Shuai DENG;Chen JIANG;Yunjie WANG;Haowen WANG

作者机构：School of Aerospace EngineeringTsirtgliua UniversityBeijing 100084China 

出 版 物：《Chinese Journal of Aeronautics》 (中国航空学报（英文版）)

年 卷 期：2021年第34卷第2期

页      面：265-278页

核心收录：

学科分类：080103[工学-流体力学] 08[工学] 080104[工学-工程力学] 0802[工学-机械工程] 0825[工学-航空宇航科学与技术] 0801[工学-力学（可授工学、理学学位）] 

主　　题：Boundary element method Dipole potentials Fast multipole method Potential flow Unsteady vortex lattice method 

摘      要：The Unsteady Vortex Lattice Method(UVLM) is a medium-fidelity aerodynamic tool that has been widely used in aeroelasticity and flight dynamics simulations. The most timeconsuming step is the evaluation of the induced velocity. Supposing that the number of bound and wake lattices is N and the computational cost is O (N2), we present an OeNT Dipole Panel Fast Multipole Method(DPFMM) for the rapid evaluation of the induced velocity in UVLM. The multipole expansion coefficients of a quadrilateral dipole panel have been derived in spherical coordinates, whose accuracy is the same as that of the Biot-Savart kernel at the same truncation degree *** methods(the loosening method and the shrinking method) are proposed and tested for space partitioning volumetric panels. Compared with FMM for vortex filaments(with three harmonics),DPFMM is approximately two times faster for N2 [103,106]. The simulation time of a multirotor(N~104) is reduced from 100 min(with unaccelerated direct solver) to 2 min(with DPFMM).