Author

# Arthur Veldman

Other affiliations: National Aerospace Laboratory, University of Twente, Delft University of Technology

Bio: Arthur Veldman is an academic researcher from University of Groningen. The author has contributed to research in topics: Discretization & Volume of fluid method. The author has an hindex of 28, co-authored 188 publications receiving 4289 citations. Previous affiliations of Arthur Veldman include National Aerospace Laboratory & University of Twente.

##### Papers published on a yearly basis

##### Papers

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TL;DR: In this paper, the authors considered some aspects of water impact and green water loading by numerically investigating a dambreak problem and water entry problems, based on the Navier-Stokes equations that describe the flow of a viscous fluid.

618 citations

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TL;DR: In this article, a symmetry-preserving discretization of the Navier-Stokes equations is shown to be stable on any grid, and conserves the total mass, momentum and kinetic energy.

582 citations

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TL;DR: In this paper, a proper orthogonal decomposition of the flow in a square lid-driven cavity at Re=22,000 is computed to educe the coherent structures in this flow and to construct a low-dimensional model for driven cavity flows.

Abstract: A proper orthogonal decomposition (POD) of the flow in a square lid-driven cavity at Re=22,000 is computed to educe the coherent structures in this flow and to construct a low-dimensional model for driven cavity flows. Among all linear decompositions, the POD is the most efficient in the sense that it captures the largest possible amount of kinetic energy (for any given number of modes). The first 80 POD modes of the driven cavity flow are computed from 700 snapshots that are taken from a direct numerical simulation (DNS). The first 80 spatial POD modes capture (on average) 95% of the fluctuating kinetic energy. From the snapshots a motion picture of the coherent structures is made by projecting the Navier–Stokes equation on a space spanned by the first 80 spatial POD modes. We have evaluated how well the dynamics of this 80-dimensional model mimics the dynamics given by the Navier–Stokes equations. The results can be summarized as follows. A closure model is needed to integrate the 80-dimensional system ...

367 citations

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TL;DR: In this article, a quasi-simultan eous method is described to calculate laminar, incompressible boundary layers interacting with an inviscid outer flow, which is consistent with the asymptotic triple-deck theory.

Abstract: A quasi-simultan eous method is described to calculate laminar, incompressible boundary layers interacting with an inviscid outer flow. The essential feature of this method is an interactive boundary condition prescribing a linear combination of pressure and displacement thickness which models the behavior of the outer flow. This way the quasi-simultaneous method avoids difficulties incurred when either direct or inverse methods are used, resulting in fast convergence of the iterative procedure involved. The method is consistent with the asymptotic triple-deck theory. Results will be presented for two problems which exhibit strong interaction between the viscous and inviscid regions: a boundary layer with a separation bubble, and the flow near the trailing edge of a flat plate. fj Nomenclature cf = skin friction coefficient, cf-Re h = mesh size in x direction H = thickness of computational boundary-layer domain L = characteristic length M,N = number of grid points in y and x direction, respectively p = pressure RJ = remainder term in discrete interaction law Re = Reynolds number , Re = U0L I v u = component of flow velocity parallel to surface Ue>ue0 = value of u at edge of boundary layer with and

196 citations

01 Jan 1981

TL;DR: In this paper, a quasi-simultan eous method is described to calculate laminar, incompressible boundary layers interacting with an inviscid outer flow, which is consistent with the asymptotic triple-deck theory.

Abstract: A quasi-simultan eous method is described to calculate laminar, incompressible boundary layers interacting with an inviscid outer flow. The essential feature of this method is an interactive boundary condition prescribing a linear combination of pressure and displacement thickness which models the behavior of the outer flow. This way the quasi-simultaneous method avoids difficulties incurred when either direct or inverse methods are used, resulting in fast convergence of the iterative procedure involved. The method is consistent with the asymptotic triple-deck theory. Results will be presented for two problems which exhibit strong interaction between the viscous and inviscid regions: a boundary layer with a separation bubble, and the flow near the trailing edge of a flat plate. fj Nomenclature cf = skin friction coefficient, cf-Re h = mesh size in x direction H = thickness of computational boundary-layer domain L = characteristic length M,N = number of grid points in y and x direction, respectively p = pressure RJ = remainder term in discrete interaction law Re = Reynolds number , Re = U0L I v u = component of flow velocity parallel to surface Ue>ue0 = value of u at edge of boundary layer with and

188 citations

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TL;DR: The Bayesian approach to regularization is reviewed, developing a function space viewpoint on the subject, which allows for a full characterization of all possible solutions, and their relative probabilities, whilst simultaneously forcing significant modelling issues to be addressed in a clear and precise fashion.

Abstract: The subject of inverse problems in differential equations is of enormous practical importance, and has also generated substantial mathematical and computational innovation. Typically some form of regularization is required to ameliorate ill-posed behaviour. In this article we review the Bayesian approach to regularization, developing a function space viewpoint on the subject. This approach allows for a full characterization of all possible solutions, and their relative probabilities, whilst simultaneously forcing significant modelling issues to be addressed in a clear and precise fashion. Although expensive to implement, this approach is starting to lie within the range of the available computational resources in many application areas. It also allows for the quantification of uncertainty and risk, something which is increasingly demanded by these applications. Furthermore, the approach is conceptually important for the understanding of simpler, computationally expedient approaches to inverse problems.

1,695 citations

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TL;DR: An introduction to the subject, emphasising the simplicity of the ideas when viewed in the context of linear algebra, and examples of the use of adjoint methods for optimising the design of business jets are presented.

Abstract: Optimal design methods involving the solution of an adjoint system of equations are an active area of research in computational fluid dynamics, particularly for aeronautical applications. This paper presents an introduction to the subject, emphasising the simplicity of the ideas when viewed in the context of linear algebra. Detailed discussions also include the extension to p.d.e.'s, the construction of the adjoint p.d.e. and its boundary conditions, and the physical significance of the adjoint solution. The paper concludes with examples of the use of adjoint methods for optimising the design of business jets.

1,004 citations

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TL;DR: An extensive review of the literature in V&V in computational fluid dynamics (CFD) is presented, methods and procedures for assessing V &V are discussed, and a relatively new procedure for estimating experimental uncertainty is given that has proven more effective at estimating random and correlated bias errors in wind-tunnel experiments than traditional methods.

948 citations

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19 May 2005TL;DR: In this article, the authors present a detailed review of liquid sloshing dynamics in rigid containers, including linear forced and non-linear interaction under external and parametric excitations.

Abstract: Preface Introduction 1. Fluid field equations and modal analysis in rigid containers 2. Linear forced sloshing 3. Viscous damping and sloshing suppression devices 4. Weakly nonlinear lateral sloshing 5. Equivalent mechanical models 6. Parametric sloshing (Faraday's waves) 7. Dynamics of liquid sloshing impact 8. Linear interaction of liquid sloshing with elastic containers 9. Nonlinear interaction under external and parametric excitations 10. Interactions with support structures and tuned sloshing absorbers 11. Dynamics of rotating fluids 12. Microgravity sloshing dynamics Bibliography Index.

920 citations

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TL;DR: In this paper, a suite of large eddy simulations (LES), in which wind turbines are modeled using the classical "drag disk" concept, is performed for various wind-turbine arrangements, turbine loading factors, and surface roughness values.

Abstract: It is well known that when wind turbines are deployed in large arrays, their efficiency decreases due to complex interactions among themselves and with the atmospheric boundary layer (ABL). For wind farms whose length exceeds the height of the ABL by over an order of magnitude, a “fully developed” flow regime can be established. In this asymptotic regime, changes in the streamwise direction can be neglected and the relevant exchanges occur in the vertical direction. Such a fully developed wind-turbine array boundary layer (WTABL) has not been studied systematically before. A suite of large eddy simulations (LES), in which wind turbines are modeled using the classical “drag disk” concept, is performed for various wind-turbine arrangements, turbine loading factors, and surface roughness values. The results are used to quantify the vertical transport of momentum and kinetic energy across the boundary layer. It is shown that the vertical fluxes of kinetic energy are of the same order of magnitude as the power...

807 citations