On the equivalence of primal and dual substructuring preconditioners.
Some practical aspects of parallel adaptive BDDC method
We describe a parallel implementation of the Balancing Domain Decomposition by Constraints (BDDC) method enhanced by an adaptive construction of coarse problem. The method is designed for numerically difficult problems, where standard choice of continuity of arithmetic averages across faces and edges of subdomains fails to maintain the low condition number of the preconditioned system. Problems of elasticity analysis of bodies consisting of different materials with rapidly changing stiffness may...
On adaptive BDDC for the flow in heterogeneous porous media
We study a method based on Balancing Domain Decomposition by Constraints (BDDC) for numerical solution of a single-phase flow in heterogeneous porous media. The method solves for both flux and pressure variables. The fluxes are resolved in three steps: the coarse solve is followed by subdomain solves and last we look for a divergence-free flux correction and pressures using conjugate gradients with the BDDC preconditioner. Our main contribution is an application of the adaptive algorithm for selection...
A priori and a posteriori error estimates for Navier-Stokes equations applied to incompressible flows
We consider the Navier-Stokes equations for the incompressible flow in channels with forward and backward steps. The paper consists of two main parts. In the first part we investigate a posteriori error estimates for the Stokes and Navier-Stokes equations on two-dimensional polygonal domains. We apply the a posteriori estimates to solve an incompressible flow problem in a domain with corners that cause singularities in the solution. Second part of the paper stands on the result on the asymptotics of...
On surrogate learning for linear stability assessment of Navier-Stokes equations with stochastic viscosity
We study linear stability of solutions to the Navier-Stokes equations with stochastic viscosity. Specifically, we assume that the viscosity is given in the form of a stochastic expansion. Stability analysis requires a solution of the steady-state Navier-Stokes equation and then leads to a generalized eigenvalue problem, from which we wish to characterize the real part of the rightmost eigenvalue. While this can be achieved by Monte Carlo simulation, due to its computational cost we study three surrogates...
Page 1