Fatma G. Eroglu

2papers

2 Papers

NAMay 15, 2017
A Modular Regularized Variational Multiscale Proper Orthogonal Decomposition for Incompressible Flows

Fatma G. Eroglu, Songul Kaya, Leo G. Rebholz

In this paper, we propose, analyze and test a post-processing implementation of a projection-based variational multiscale (VMS) method with proper orthogonal decomposition (POD) for the incompressible Navier-Stokes equations. The projection-based VMS stabilization is added as a separate post-processing step to the standard POD approximation, and since the stabilization step is completely decoupled, the method can easily be incorporated into existing codes, and stabilization parameters can be tuned independent from the time evolution step. We present a theoretical analysis of the method, and give results for several numerical tests on benchmark problems which both illustrate the theory and show the proposed method's effectiveness.

NAOct 24, 2018
Long time stability of a linearly extrapolated blended BDF scheme for multiphysics flows

Aytekin Çıbık, Fatma G. Eroglu, Songul Kaya

This paper investigates the long time stability behavior of multiphysics flow problems, namely the Navier-Stokes equations, natural convection and double-diffusive convection equations with an extrapolated blended BDF time-stepping scheme. This scheme combines the two-step BDF and three-step BDF time stepping schemes. We prove unconditional long time stability theorems for each of flow systems. Various numerical tests are given for large time step sizes in long time intervals in order to support theoretical results.