TY - JOUR
T1 - High frequency acoustic simulations via FMM accelerated BEM
JF - 19th Internal congress on acoustics
Y1 - 2007
A1 - Gumerov, Nail A.
A1 - Duraiswami, Ramani
AB - High frequency simulations of acoustics are among the most expensive problems to simulate. Inpractice 6 to 10 points per wavelength are required. Since the wavenumber k is inversely proportional to wavelength, if a numerical method is a surface based method (such as the BEM), then problem size scales as O(k2D2), where D is the size of the domain. Dense matrices appear and typical iter- ative solution can be achieved for O(k4D4) memory and O(k4D4) per iteration cost. We employ an algorithm based on the fast multipole method (FMM) using coaxial and diagonal translation operators based on the frequency of simulation to reduce the memory requirements and per iteration cost to O(k2D2 log kD) for larger kD (kD ~250). The number of iterations needed depend upon the condition of the matrix, and preconditioning chosen. Preconditioned Krylov methods such as the flexible gen- eralized minimum residual method (FGMRES), with preconditioning based upon a lower accuracy FMM, usually ensure a convergent iteration. Example calculations are presented.
VL - 159
ER -