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Diaz Cortes, G.B. (author), Vuik, C. (author), Jansen, J.D. (author)

report 2016
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de Jong, M.A. (author), Vuik, C. (author)

report 2016
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Qiu, Y. (author), van Gijzen, M.B. (author), van Wingerden, J.W. (author), Verhaegen, M. (author), Vuik, C. (author)
Multilevel sequentially semiseparable (MSSS) matrices form a class of structured matrices that have low-rank off-diagonal structure, which allows the matrix-matrix operations to be performed in linear computational complexity. MSSS preconditioners are computed by replacing the Schur complements in the block LU factorization of the global linear...
report 2015
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Qiu, Y. (author), Van Gijzen, M.B. (author), Van Wingerden, J.W. (author), Verhaegen, M.H.G. (author), Vuik, C. (author)
In this manuscript, we study preconditioning techniques for optimal in-domain control of the Navier-Stokes equation, where the control only acts on a few parts of the domain. Optimization and linearization of the optimal in-domain control problem results in a generalized linear saddle-point system. The Schur complement for the generalized saddle...
report 2015
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Van Zwieten, J.S.B. (author), Sanderse, B. (author), Hendrix, M.H.V. (author), Vuik, C. (author), Henkes, R.A.W.M. (author)
One-dimensional models for multiphase flow in pipelines are commonly discretised using first-order Finite Volume (FV) schemes, often combined with implicit time-integration methods. While robust, these methods introduce much numerical diffusion depending on the number of grid points. In this paper we propose a high-order, space-time...
report 2015
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Qiu, Y. (author), Van Gijzen, M.B. (author), Van Wingerden, J.W. (author), Verhaegen, M. (author), Vuik, C. (author)
In this manuscript, we study preconditioning techniques for optimal in-domain control of the Navier-Stokes equation, where the control only acts on a few parts of the domain. Optimization and linearization of the optimal in-domain control problem results in a generalized linear saddle-point system. The Schur complement for the generalized saddle...
report 2015
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Tang, J.M. (author), Vuik, C. (author), Witteveen, C. (author)
In this report, the recent and future contributions of experts and groups of Delft University of Technology (DUT) on the topic of smart grids (SG) are presented. This may provide guidelines on how DUT can contribute in current and future SG projects, such as the current TKI project on “Smart Grid Evolution (SGE): Developing a service platform...
report 2014
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Qiu, Y. (author), Van Gijzen, M.B. (author), Van Wingerden, J.W. (author), Verhaegen, M. (author), Vuik, C. (author)
In this paper, we consider preconditioning for PDE-constrained optimization problems. The underlying problems yield a linear saddle-point system. We study a class of preconditioners based on multilevel sequentially semiseparable (MSSS) matrix computations. The novel global preconditioner is to make use of the global structure of the saddle-point...
report 2014
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De Ronde, J.G. (author), Baart, F. (author), Katsman, C.A. (author), Vuik, V. (author)
Voor het Nederlandse beleid van kustveiligheid en kustlijnhandhaving is een betrouwbare en robuuste schatting van de zeespiegelstijging belangrijk. Het voorliggende rapport beschrijft verschillende exercities die zijn gedaan om de zeespiegelstijging langs de Nederlandse kust met een hogere betrouwbaarheid vast te stellen ten opzichte van eerdere...
report 2014
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Qiu, Y. (author), Van Gijzen, M.B. (author), Van Wingerden, J. (author), Verhaegen, M. (author), Vuik, C. (author)
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...
report 2013
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He, X. (author), Vuik, C. (author)
In this report we explore the performance of the SIMPLER , augmented Lagrangian, ’grad-div’ preconditioners and their variants for the two-by-two block systems arising in the incompressible Navier-Stokes equations. The lid-driven cavity and flow over a finite flat plate are chosen as the benchmark problems. For each problem Reynolds number...
report 2013
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Vuik, K. (author), Daalderop, F. (author), Wilders, P. (author), Daudt, J. (author), Van Kints, R. (author), Koolstra, K. (author), Van den Oever, J. (author), Lobbezoo, B. (author)
This report gives an overview of the work done on MUMIE [2] at TU Delft for the academic year 2012 - 2013. Reports from previous years can be found on our relevant support website [3]. In October 2012 there was a kick-off meeting at TU Berlin regarding the S3M2 project [1]. During this meeting, every participant was assigned to develop material...
report 2013
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Thomas, R. (author), Lahaye, D.J.P. (author), Vuik, C. (author), Van der Sluis, L. (author)
report 2013
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He, X. (author), Neytcheva, M. (author), Vuik, C. (author)
This paper deals with fast and reliable numerical solution methods for the incompressible non-Newtonian Navier-Stokes equations. To handle the nonlinearity of the governing equations, the Picard and Newton methods are used to linearize these coupled partial differential equations. For space discretization we use the finite element method and...
report 2013
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Vuik, V. (author), Van Balen, W. (author)
In opdracht van het Deltaprogramma Kust is in kaart gebracht hoe het gesteld is met de huidige veiligheid van de Nederlandse kust. Als maat voor de veiligheid is de overstromingskans van de kustverdediging genomen. Deze overstromingskans kan opgevat worden als de kans op falen van een willekeurige locatie langs de kering, zodanig dat een...
report 2012
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Lingen, F.J. (author), Bonnier, P.G. (author), Brinkgreve, R.B.J. (author), Van Gijzen, M.B. (author), Vuik, C. (author)
report 2012
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Van Slingerland, P. (author), Vuik, C. (author)
report 2012
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Van Slingerland, P. (author), Vuik, C. (author)
report 2012
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Idema, R. (author), Papaefthymiou, G. (author), Lahaye, D.J.P. (author), Vuik, C. (author), Van der Sluis, L. (author)
Current and future developments in the power system industry demand fast power flow solvers for larger power flow problems. The established methods are no longer viable for such problems, as they are not scalable in the problem size. In this paper, the use of Newton-Krylov power flow methods is proposed, and a multitude of preconditioning...
report 2012
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Jönsthövel, T.B. (author), Van Gijzen, M.B. (author), Vuik, C. (author), Scarpas, A. (author)
Large discontinuities in material properties, such as encountered in composite materials, lead to ill-conditioned systems of linear equations. These discontinuities give rise to small eigenvalues that may negatively affect the convergence of iterative solution methods such as the Preconditioned Conjugate Gradient (PCG) method. This paper...
report 2011
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