Print Email Facebook Twitter Evaluation of Multilevel Sequentially Semiseparable Preconditioners on CFD Benchmark Problems Using IFISS Title Evaluation of Multilevel Sequentially Semiseparable Preconditioners on CFD Benchmark Problems Using IFISS Author Qiu, Y. Van Gijzen, M.B. Van Wingerden, J. Verhaegen, M. Vuik, C. Faculty Electrical Engineering, Mathematics and Computer Science Department Delft Institute of Applied Mathematics Date 2013-12-31 Abstract This paper studies a new preconditioning technique for sparse systems arising from discretized partial differential equations (PDEs) in computational fluid dynamics (CFD), which exploit the multilevel sequentially semiseparable (MSSS) structure of the system matrix. MSSS matrix computations give a data-sparse way to approximate the LU factorization of a sparse matrix from discretized PDEs in linear computational complexity with respect to the problem size. In contrast to the standard block preconditioners, we exploit the global MSSS structure of the 2 by 2 block system from the discretized Stokes equation and linearized Navier-Stokes equation. This avoids the approximation of the Schur complement, which is a big advantage over standard block preconditioners. Numerical experiments on standard CFD benchmark problems in IFISS were carried out to evaluate the performance of the MSSS preconditioners. It was illustrated that the MSSS preconditioner yields mesh size independence convergence. Moreover, the convergence is almost insensitive to the viscosity parameter. Comparison with the algebraic multigrid (AMG) method and the geometric multigrid (GMG) method, the MSSS preconditioning technique is more robust than both the AMG method and the GMG method, and considerably faster than the AMG method. Subject partial differential equationsmultilevel sequentially semiseparable matricespreconditionerscomputational fluid dynamicsmultigrid method To reference this document use: http://resolver.tudelft.nl/uuid:f107d33a-426d-4dfd-ba66-1bcaaee71274 Publisher Delft University of Technology, Faculty of Electrical Engineering, Mathematics and Computer Science, Delft Institute of Applied Mathematics ISSN 1389-6520 Source Reports of the Delft Institute of Applied Mathematics, 13-11 Part of collection Institutional Repository Document type report Rights (c)2013 The Authors Files PDF 13-11_MSSS_CFD_BENCHMARKT ... U_2013.pdf 4.7 MB Close viewer /islandora/object/uuid:f107d33a-426d-4dfd-ba66-1bcaaee71274/datastream/OBJ/view