Stephen T. Rowe

2papers

2 Papers

NAFeb 16, 2015
A Novel Galerkin Method for Solving PDEs on the Sphere Using Highly Localized Kernel Bases

F. J. Narcowich, Stephen T. Rowe, Joseph D. Ward

We present a novel Galerkin method for solving partial differential equations on the sphere. The problem is discretized by a highly localized basis which is easily constructed. The stiffness matrix entries are computed by a recently developed quadrature formula unique to the localized bases we consider. We present error estimates and investigate the stability of the discrete stiffness matrix. Implementation and numerical experiments are discussed.

NAJan 12, 2016
A Meshless Galerkin Method For Non-Local Diffusion Using Localized Kernel Bases

Richard B. Lehoucq, Francis J. Narcowich, Stephen T. Rowe et al.

We introduce a meshless method for solving both continuous and discrete variational formulations of a volume constrained, nonlocal diffusion problem. We use the discrete solution to approximate the continuous solution. Our method is nonconforming and uses a localized Lagrange basis that is constructed out of radial basis functions. By verifying that certain inf-sup conditions hold, we demonstrate that both the continuous and discrete problems are well-posed, and also present numerical and theoretical results for the convergence behavior of the method. The stiffness matrix is assembled by a special quadrature routine unique to the localized basis. Combining the quadrature method with the localized basis produces a well-conditioned, symmetric matrix. This then is used to find the discretized solution.