Numerical Simulation of Time-Harmonic Waves in Inhomogeneous Media using Compact High Order Schemes

In many problems, one wishes to solve the Helmholtz equation with vari- able coefficients within the Laplacian-like term and use a high order accurate method (e.g., fourth order accurate) to alleviate the points-per-wavelength constraint by re- ducing the dispersion errors. The variation of coefficients in the equation may be due to an inhomogeneous medium and/or non-Cartesian coordinates. This renders exist- ing fourth order finite difference methods inapplicable. We develop a new compact scheme that is provably fourth order accurate even for these problems. We present numerical results that corroborate the fourth order convergence rate for several model problems.

[1]  N. K. Kulman,et al.  Method of difference potentials and its applications , 2001 .

[2]  Semyon Tsynkov,et al.  High-Order Two-Way Artificial Boundary Conditions for Nonlinear Wave Propagation with Backscattering , 2000 .

[3]  Stefan A. Sauter,et al.  Is the Pollution Effect of the FEM Avoidable for the Helmholtz Equation Considering High Wave Numbers? , 1997, SIAM Rev..

[4]  Semyon Tsynkov,et al.  High-order numerical method for the nonlinear Helmholtz equation with material discontinuities in one space dimension , 2007, J. Comput. Phys..

[5]  Eli Turkel,et al.  Iterative schemes for high order compact discretizations to the exterior Helmholtz equation , 2012 .

[6]  G. Sutmann Compact finite difference schemes of sixth order for the Helmholtz equation , 2007 .

[7]  Olaf Schenk,et al.  Weighted Matchings for Preconditioning Symmetric Indefinite Linear Systems , 2006, SIAM J. Sci. Comput..

[8]  V. Smirnov,et al.  A course of higher mathematics , 1964 .

[9]  Iain S. Duff,et al.  Strategies for Scaling and Pivoting for Sparse Symmetric Indefinite Problems , 2005, SIAM J. Matrix Anal. Appl..

[10]  I. Singer,et al.  High-order finite difference methods for the Helmholtz equation , 1998 .

[11]  Heinz-Otto Kreiss,et al.  Difference Approximations for the Second Order Wave Equation , 2002, SIAM J. Numer. Anal..

[12]  HEINZ-OTTO KREISS,et al.  A Second Order Accurate Embedded Boundary Method for the Wave Equation with Dirichlet Data , 2005, SIAM J. Sci. Comput..

[13]  Semyon Tsynkov,et al.  A high-order numerical method for the nonlinear Helmholtz equation in multidimensional layered media , 2009, J. Comput. Phys..

[14]  Semyon Tsynkov,et al.  On the Definition of Surface Potentials for Finite-Difference Operators , 2003, J. Sci. Comput..

[15]  J. Dargahi,et al.  A new 9-point sixth-order accurate compact finite-difference method for the Helmholtz equation , 2007 .

[16]  Semyon Tsynkov,et al.  A Compact Fourth Order Scheme for the Helmholtz Equation in Polar Coordinates , 2010, J. Sci. Comput..

[17]  Timothy A. Davis,et al.  Direct methods for sparse linear systems , 2006, Fundamentals of algorithms.

[18]  A. Bayliss,et al.  On accuracy conditions for the numerical computation of waves , 1985 .

[19]  Semyon Tsynkov,et al.  Numerical solution of the nonlinear Helmholtz equation using nonorthogonal expansions , 2005 .

[20]  Stefan Nilsson,et al.  Stable Difference Approximations for the Elastic Wave Equation in Second Order Formulation , 2007, SIAM J. Numer. Anal..

[21]  I. Singer,et al.  SIXTH-ORDER ACCURATE FINITE DIFFERENCE SCHEMES FOR THE HELMHOLTZ EQUATION , 2006 .

[22]  Timothy A. Davis,et al.  Direct Methods for Sparse Linear Systems (Fundamentals of Algorithms 2) , 2006 .

[23]  M. Agranovich,et al.  Generalized method of eigenoscillations in diffraction theory , 1999 .

[24]  E. Turkel,et al.  Operated by Universities Space Research AssociationAccurate Finite Difference Methods for Time-harmonic Wave Propagation* , 1994 .

[25]  R. C. Engels,et al.  AN OPTIMAL FINITE DIFFERENCE REPRESENTATION FOR A CLASS OF LINEAR PDE'S WITH APPLICATION TO THE HELMHOLTZ EQUATION , 1999 .

[26]  Robert J. Lee,et al.  Reducing the phase error for finite-difference methods without increasing the order , 1998 .