International Journal for Numerical Methods in Fluids

Cover image for Vol. 79 Issue 12

Early View (Online Version of Record published before inclusion in an issue)

Edited By: Charbel Farhat, Wolfgang A. Wall

Impact Factor: 1.244

ISI Journal Citation Reports © Ranking: 2014: 18/31 (Physics Fluids & Plasmas); 40/99 (Mathematics Interdisciplinary Applications); 63/102 (Computer Science Interdisciplinary Applications); 73/137 (Mechanics)

Online ISSN: 1097-0363

Associated Title(s): International Journal for Numerical Methods in Biomedical Engineering, International Journal for Numerical Methods in Engineering, International Journal of Numerical Modelling: Electronic Networks, Devices and Fields, Numerical Linear Algebra with Applications


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  1. Research Articles

    1. A mass-conserving level-set method for simulation of multiphase flow in geometrically complicated domains

      F. Raees, D. R. van der Heul and C. Vuik

      Article first published online: 8 NOV 2015 | DOI: 10.1002/fld.4188

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      We present the extension of the MCLS method toward unstructured triangular grids for two phase flow. The VoF function and the inverse function derived for a triangular mesh are very simple, robust and efficient to evaluate. Our approach is significantly more efficient and robust than the original MCLS formulation. Numerical experiments indicate the LS field converges with second order accuracy in space and mass is conserved up to machine precision.

    2. Developing a hybrid flux function suitable for hypersonic flow simulation with high-order methods

      Dongfang Wang, Xiaogang Deng, Guangxue Wang and Yidao Dong

      Article first published online: 8 NOV 2015 | DOI: 10.1002/fld.4186

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      In this paper, we develop a very robust hybrid flux function to overcome the shock instability in hypersonic flow simulation with high-order methods. Multidimensional dissipation and entropy correction based on local flow field are introduced to enhance the robustness and resolution of the hybrid flux function. A series of tests shows that this new hybrid flux function with a fifth-order weighted compact nonlinear scheme (WCNS) is not only robust for shock-capturing but also accurate for hypersonic heat transfer prediction.

    3. The intersection marker method for 3D interface tracking of deformable surfaces in finite volumes

      Mark Ho, Guan Yeoh, John Reizes and Victoria Timchenko

      Article first published online: 25 OCT 2015 | DOI: 10.1002/fld.4182

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      The intersection marker method is a novel approach for modelling an arbitrary 3D surface within an array of cubic control volumes. Intersection marker's novelty lies in its ability to remesh the interface on a cell-by-cell basis whilst maintaining surface continuity and local volume conservation without the use of permanent surface markers.

    4. Optimization of the ADER-DG method in GPU applied to linear hyperbolic PDEs

      Cristóbal E. Castro, Jörn Behrens and Christian Pelties

      Article first published online: 25 OCT 2015 | DOI: 10.1002/fld.4179

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      In the figure, we show a convergence test considering the 2D linear elastic wave equation. We compare double precision and single precision of the graphics processor unit implementation against the CPU code SeisSol for different orders from second (P1) to sixth (P5). In the vertical axis, the error level is obtained using the L_2 norm. The figure on the left depicts the error against mesh size, while on the right, the horizontal axis represents computational time.

    5. Unsteady shock-fitting for unstructured grids

      A. Bonfiglioli, R. Paciorri and L. Campoli

      Article first published online: 23 OCT 2015 | DOI: 10.1002/fld.4183

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      An unstructured, shock-fitting algorithm, originally developed to simulate steady flows, has been further developed to make it capable of dealing with unsteady flows. The present paper discusses and analyses the additional features required to extend to unsteady flows the steady algorithm.

    6. Modal decomposition-based global stability analysis for reduced order modeling of 2D and 3D wake flows

      Witold Stankiewicz, Marek Morzyński, Krzysztof Kotecki, Robert Roszak and Michał Nowak

      Article first published online: 23 OCT 2015 | DOI: 10.1002/fld.4181

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      The method for computation of stability modes for two- and three-dimensional flows is presented. The method bases on the Dynamic Mode Decomposition of the data resulting from Direct Numerical Simulation of the flow in the regime close to steady flow. The resulting modes resemble the eigenmodes of global stability analysis and are used to design low dimensional Galerkin models of theflow.

    7. A mass-conservative staggered immersed boundary model for solving the shallow water equations on complex geometries

      Alberto Canestrelli, Aukje Spruyt, Bert Jagers, Rudy Slingerland and Mart Borsboom

      Article first published online: 23 OCT 2015 | DOI: 10.1002/fld.4180

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      An immersed boundary model for shallow water equations based on a staggered alternating direction implicit solver is proposed. The scheme is implicit, and therefore, the time step is not constrained by the Courant–Friedrichs–Lewy condition. The model accurately describes 2D and 3D flow in both straight and curved channels.

    8. A vertex-centered linearity-preserving discretization of diffusion problems on polygonal meshes

      Jiming Wu, Zhiming Gao and Zihuan Dai

      Article first published online: 13 OCT 2015 | DOI: 10.1002/fld.4178

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      The new vertex-centered scheme possesses the three properties: the local conservation, the symmetry and positive definiteness, and the linearity preserving (preserve the linear solution exactly), which is rarely seen in the existing cell-centered or vertex-centered scheme. The coercivity of the scheme is rigorously analyzed on arbitrary mesh size under some weak geometry assumptions. Several numerical tests show that the new scheme has approximately second-order accuracy on general polygonal meshes.

    9. A well-balanced scheme to capture non-explicit steady states in the Euler equations with gravity

      Vivien Desveaux, Markus Zenk, Christophe Berthon and Christian Klingenberg

      Article first published online: 6 OCT 2015 | DOI: 10.1002/fld.4177

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      We present a finite volume scheme to approximate the Euler equations with a gravitational source term based on a relaxation method. A particular attention is paid on the preservation of the hydrostatic steady-state solutions of the system. Moreover, the scheme is also proven to be robust and entropy preserving.

    10. Development of new finite volume schemes on unstructured triangular grid for simulating the gas–liquid two-phase flow

      Wen Zhou, Jie Ouyang, Lin Zhang, Jin Su, Xiaodong Wang and Binxin Yang

      Article first published online: 5 OCT 2015 | DOI: 10.1002/fld.4174

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      This paper develops a new finite volume scheme for solving the level set equation. The new scheme can preserve the mass conservation accurately in level set method.

    11. The non-reflective interface: an innovative forcing technique for computational acoustic hybrid methods

      Stephane Redonnet, David P. Lockard, Mehdi R. Khorrami and Meelan. M. Choudhari

      Article first published online: 5 OCT 2015 | DOI: 10.1002/fld.4173

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      Regarding those hybrid methods in acoustics for which the propagation stage is based on advanced Computational AeroAcoustics (CAA) techniques, the present article introduces an original forcing technique, namely, the Non-Reflective Interface (NRI), to enable the transfer of an acoustic signal from an a priori noise generation stage into a CAA-based acoustic propagation phase. Unlike most existing forcing techniques, the NRI makes the associated CAA-based hybrid approach compatible with a large variety of realistic noise problems.

    12. A new numerical model for simulations of wave transformation, breaking and long-shore currents in complex coastal regions

      F. Gallerano, G. Cannata and F. Lasaponara

      Article first published online: 2 OCT 2015 | DOI: 10.1002/fld.4164

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      In this paper, we propose a model based on a new contravariant integral form of fully nonlinear Boussinesq equations in order to simulate wave transformation phenomena, wave breaking, and near shore currents in computational domains representing the complex morphology of real coastal regions. The aforementioned contravariant integral form, in which Christoffel symbols are absent, is characterized by the fact that the continuity equation does not include any dispersive term. We propose an original shock-capturing scheme, for the numerical integration of the fully nonlinear Boussinesq equation, which is based on a genuinely two-dimensional weighted essentially non-oscillatory reconstruction procedure. It has been demonstrated that the presented Boussinesq model can be used for the simulation of wave fields and nearshore currents in the coastal region characterized by morphologically complex coastal lines and irregular seabeds and by the presence of maritime infrastructures.

    13. Wall-based reduced-order modelling

      Davide Lasagna and Owen R. Tutty

      Article first published online: 1 OCT 2015 | DOI: 10.1002/fld.4163

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      A novel approach for model order reduction for incompressible fluid flows is discussed. A compact set of elementary ‘wall basis functions’ is first derived via POD to provide a low-order representation of the spatial distribution of the surface stresses. A dynamical model, providing the temporal dynamics of the amplitudes of the wall structures, is then identified from data. The method is applied to the paradigmatic example of modelling the flow past a circular cylinder at Re = 200.

    14. A simple finite element method for Stokes flows with surface tension using unfitted meshes

      H. Ji and Q. Zhang

      Article first published online: 30 SEP 2015 | DOI: 10.1002/fld.4176

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      For the static three-dimensional bubble, the proposed method reduces the oscillations near the interface substantially. Note that coefficient matrix of the resulting system of the proposed method is the same as that of the traditional FEM.

    15. L2Roe: a low dissipation version of Roe's approximate Riemann solver for low Mach numbers

      K. Oßwald, A. Siegmund, P. Birken, V. Hannemann and A. Meister

      Article first published online: 24 SEP 2015 | DOI: 10.1002/fld.4175

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      A modification of the Roe scheme is discussed that improves the dissipation of kinetic energy at the highest resolved wave numbers in a low Mach number test case of decaying isotropic turbulence. This is performed by scaling the jumps in all discrete velocity components within the numerical flux function. An asymptotic analysis is used to show the correct pressure scaling at low Mach numbers and to identify the reduced numerical dissipation in that regime, both of the new method L2Roe and the two other methods previously suggested by other authors.

    16. Evaluation of the deflated preconditioned CG method to solve bubbly and porous media flow problems on GPU and CPU

      R. Gupta, D. Lukarski, M. B. van Gijzen and C. Vuik

      Article first published online: 24 SEP 2015 | DOI: 10.1002/fld.4170

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      In this work, we present the implementation of the deflated preconditioned conjugate gradient method on the GPU using PARALUTION. Through our experiments with two different problems, we prove that it is advantageous to use this method in comparison with optimized CPU implementations of preconditioned CG methods.

    17. An efficient WENO limiter for discontinuous Galerkin transport scheme on the cubed sphere

      Wei Guo, Ramachandran D. Nair and Xinghui Zhong

      Article first published online: 23 SEP 2015 | DOI: 10.1002/fld.4171

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      A simple and efficient limiter based on the weighted essentially non-oscillatory methodology is incorporated in the discontinuous Galerkin transport framework on the cubed sphere, with the following distinctive features: high-order accurate, good non-oscillatory properties, easy to implement, and can avoid ghost cells when applied to a corner cell of the cubed sphere.

    18. A parallel monolithic algorithm for the numerical simulation of large-scale fluid structure interaction problems

      Ali Eken and Mehmet Sahin

      Article first published online: 23 SEP 2015 | DOI: 10.1002/fld.4169

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      A novel FSI algorithm is proposed for the large-scale simulation of fluid-structure interaction problems in a fully coupled form. A special attention is given to satisfy both the local and global discrete geometric conservation law (DGCL) in order to conserve the total fluid volume/mass in machine precision. Large-scale numerical results are presented for several classical FSI benchmark problems.

    19. Accurate and consistent particle tracking on unstructured grids

      G. S. Ketefian, E. S. Gross and G. S. Stelling

      Article first published online: 23 SEP 2015 | DOI: 10.1002/fld.4168

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      We present a new 2-D Lagrangian particle-tracking method on triangular unstructured grids that is more accurate than previously published methods and does not suffer from unphysical particle clustering. We also present the complete analytic solution to the 2-D system of ordinary differential equations (ODEs) governing particle tracks, the analytic solution to the linear system of locally mass-conserving constraints used to obtain the coefficients in the ODEs, and numerical tests demonstrating the accuracy and mass-conserving property of the method.

    20. An efficient semi-implicit subgrid method for free-surface flows on hierarchical grids

      F. W. Platzek, G. S. Stelling, J. A. Jankowski, R. Patzwahl and J. D. Pietrzak

      Article first published online: 22 SEP 2015 | DOI: 10.1002/fld.4172

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      We present a semi-implicit method for free surface flows that incorporates high-resolution geometric data on subgrid level and applies a hierarchical grid solution strategy. The subgrid method makes sure that coarse-grid solutions within the hierarchical grid approach resemble the fine-grid solution, thereby considerably improving the efficiency and accuracy of the hydrodynamic model and providing automatic insight in grid convergence. A novel interpolation method that avoids the introduction of disturbances was applied to transfer data from coarse to fine grids.

    21. Roe-type Riemann solver for gas–liquid flows using drift-flux model with an approximate form of the Jacobian matrix

      Christiano Garcia da Silva Santim and Eugênio Spanó Rosa

      Article first published online: 22 SEP 2015 | DOI: 10.1002/fld.4165

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    22. A study of reduced-order 4DVAR with a finite element shallow water model

      M. U. Altaf, M. Ambrozic, M. F. McCabe and I. Hoteit

      Article first published online: 16 SEP 2015 | DOI: 10.1002/fld.4167

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      Four-dimensional variational data assimilation is frequently used to improve model forecasting skills. The method although requires computation of the gradient of the cost function, which requires huge programming burden to build the adjoint model. Here, comparative performance analysis on a nonlinear finite element shallow water model is performed using alternate four-dimensional variational data assimilation methodologies based on proper orthogonal decomposition. These approaches are nonintrusive in nature and do not require any modifications to system code; thus, they are very easy to implement.

    23. An efficient and accurate fully discrete finite element method for unsteady incompressible Oldroyd fluids with large time step

      Yingwen Guo and Yinnian He

      Article first published online: 14 SEP 2015 | DOI: 10.1002/fld.4084

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      We introduce a second order in time fully discrete finite element method for unsteady incompressible Oldroyd fluids. This new approach reduces the nonlinear equations to an almost unconditionally stable and convergent system of linear equations that can be solved efficiently and accurately with a large time step. Extensive numerical tests and two benchmark problems of the Oldroyd fluids are simulated for investigating temporal and spatial accuracy in different situations.

    24. Assessment of global linear stability analysis using a time-stepping approach for compressible flows

      Y. Ohmichi and K. Suzuki

      Article first published online: 10 SEP 2015 | DOI: 10.1002/fld.4166

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      A set of numerical techniques for global linear stability analysis of compressible flows is developed and assessed. We demonstrated that the proposed method can accurately analyze the global stability of low and high subsonic Mach number flows and be performed with low memory consumption. Numerical experiments show that the outflow boundary causes spurious unstable modes and the radiation and outflow boundary condition and the extension of the computational domain with grid stretching keep the spurious unstable modes to a minimum.

    25. Two-level consistent splitting methods based on three corrections for the time-dependent Navier–Stokes equations

      Qingfang Liu, Yanren Hou, Zhiheng Wang and Jiakun Zhao

      Article first published online: 8 SEP 2015 | DOI: 10.1002/fld.4087

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      For large viscosity case, Stokes correction method is a good choice. For moderate viscosity case, Newton correction method can obtain the best accuracy. For small viscosity case, Oseen correction method is preferable for the long-time simulations.

    26. Immersed boundary method for unsteady kinetic model equations

      Cem Pekardan, Sruti Chigullapalli, Lin Sun and Alina Alexeenko

      Article first published online: 7 SEP 2015 | DOI: 10.1002/fld.4085

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      We present immersed boundary method formulations for the Boltzmann model kinetic equation for solution of unsteady rarefied flows. The first formulation is based on the interpolation often applied for continuum flows, whereas the relaxation method exploits locally an analytical solution of the collisionless Boltzmann equation. The third approach combines relaxation of the velocity distribution function with interpolation of macroparameters and shows the fastest convergence.

    27. An adaptive finite element method for the modeling of the equilibrium of red blood cells

      Aymen Laadhari, Pierre Saramito and Chaouqi Misbah

      Article first published online: 3 SEP 2015 | DOI: 10.1002/fld.4086

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      This contribution is concerned with the numerical modeling of the equilibrium shapes of RBCs. We propose a mixed finite element approximation based on the level set method. An anisotropic mesh adaptation technique allows more computational accuracy in the vicinity of the cell. We present numerical experiments that illustrate the main features of the proposed method. The accuracy of the finite element computations is demonstrated through numerical comparisons with the solutions of a reduced order problem.

    28. Solution of the incompressible Navier–Stokes equations by the method of lines

      Matteo Strumendo

      Article first published online: 3 SEP 2015 | DOI: 10.1002/fld.4083

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      The numerical method of lines is applied to the solution of the two-dimensional unsteady Navier–Stokes equations for incompressible laminar flows. The Navier–Stokes equations are first discretized (in space) on a staggered grid. The discretized Navier–Stokes equations form an index 2 system of differential algebraic equations, which are reduced to a system of ordinary differential equations using the discretized form of the continuity equation. The resulting ordinary differential equations are solved using the backward differentiation formulas.

    29. High-accuracy upwind method using improved characteristics speeds for incompressible flows

      Iman Abdollahi, Kamiar Zamzamian and Reza Fathollahi

      Article first published online: 27 AUG 2015 | DOI: 10.1002/fld.4088

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      In this study, the Nervier–Stokes equations for incompressible flows, modified by the artificial compressibility method, are investigated numerically. To calculate convective fluxes a new high-accuracy characteristics-based scheme (HACB) based on improved characteristics speeds is presented in this paper. Comparing the HACB scheme with the original characteristic-based method, it is found that the new proposed scheme is more accurate and has faster convergence rate than the older one.

    30. Compressive advection and multi-component methods for interface-capturing

      Dimitrios Pavlidis, Jefferson L. M. A. Gomes, Zhihua Xie, James R. Percival, Christopher C. Pain and Omar K. Matar

      Article first published online: 27 AUG 2015 | DOI: 10.1002/fld.4078

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      We present theory and apply an interface-capturing method for multiphase flow problems in 2D and 3D with emphasis on the use of adaptive unstructured finite element meshes. The method is mass-conserving and able to ensure that key forces such as buoyancy and hydrostatic pressure are exactly balanced. In addition, arbitrary numbers of phases with arbitrary equations of state can be modelled as demonstrated here.

    31. Lattice Boltzmann method for the fractional sub-diffusion equation

      Jianying Zhang and Guangwu Yan

      Article first published online: 25 AUG 2015 | DOI: 10.1002/fld.4089

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      Lattice Boltzmann method can be used to implement the numerical simulation of the fractional sub-diffusion equation. The results by the lattice Boltzmann model are compared with the results of classical method. This figure is a snapshot of the three-dimensional example by Lattice Boltzmann method.

    32. Dispersion error reduction for acoustic problems using the smoothed finite element method (SFEM)

      Lingyun Yao, Yunwu Li and Li Li

      Article first published online: 25 AUG 2015 | DOI: 10.1002/fld.4081

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      The smoothed finite element method model behaves much softer than the standard finite element method model and hence can significantly reduce the dispersion error in the numerical solution. Results of both theoretical and numerical experiments will support these important findings.

    33. Improved MPS method with variable-size particles

      Xiao Chen, Zhong-Guo Sun, Ling Liu and Guang Xi

      Article first published online: 14 AUG 2015 | DOI: 10.1002/fld.4082

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      Proposed VSP-MPS method with variable resolution minimizes the particle clustering to improve the computational stability and efficiency with high accuracy. Particles with different sizes have identical effect radii to meet Newton's third law, and new gradient model and additional weight function based on a cubic spline function are proposed to balance the overstated gradient between large and small particles. A five-step article splitting and coalescing algorithm is proposed with random distribution scheme to reduce the particle clustering, and multiple particle sizes could be found in each single resolution area which is new from similar schemes.

    34. New hybrid Cartesian cut cell/enriched multipoint flux approximation approach for modelling and quantification of structural uncertainties in petroleum reservoirs

      Mohammad Ahmadi, Mike Christie, Margot Gerritsen and Hamid Bazargan

      Article first published online: 13 AUG 2015 | DOI: 10.1002/fld.4075

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      To quantify the structural uncertainty, an efficient methodology based on Cartesian cut cell method is developed that decouples the model from its representation onto the grid. Reduced numerical accuracy due to cell degeneracies is adequately compensated with extended enriched multipoint flux approximation method. Method robustness and consistency are verified with correct impression of flow behaviour from variations in geological structures. Significant improvements in the quality of reservoir recovery forecasts and reservoir volume estimation are presented for uncertain structures.

    35. Development of optimized interpolation schemes with spurious modes minimization

      G. Cunha and S. Redonnet

      Article first published online: 12 AUG 2015 | DOI: 10.1002/fld.4079

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      In the present work, a novel optimization technique for interpolation processes is proposed. Such a technique, which is hereafter designed as the interpolation by parts, allows interpolating accurately a given signal, while minimizing its possible degradation in terms of spurious modes generation. As a result, compared with its standard counterpart, any interpolation by parts-optimized interpolation scheme exhibits improved characteristics, such as a generation of spurious modes that is greatly reduced (up to a 99% factor).

    36. From level set to volume of fluid and back again at second-order accuracy

      Miles Detrixhe and Tariq D. Aslam

      Article first published online: 10 AUG 2015 | DOI: 10.1002/fld.4076

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      We present methods for computing either the level set function or volume fraction field from the other at second order accuracy. This work includes a novel interface reconstruction algorithm in three dimensions that requires a smaller local block of volume fractions than existing algorithms. All of the numerical examples confirm second order accuracy on both uniform and tree-based adaptive grids.

    37. Preventing numerical oscillations in the flux-split based finite difference method for compressible flows with discontinuities, II

      Zhiwei He, Yousheng Zhang, Xinliang Li and Baolin Tian

      Article first published online: 7 AUG 2015 | DOI: 10.1002/fld.4080

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      It can be theoretically proven that if the isobars of a material are vertical lines, the combination of using the local characteristic decomposition and the global Lax-Friedrichs flux vector splitting (FVS) can avoid velocity and pressure oscillations of contact discontinuities in this material for finite difference weighted essentially non-oscillatory schemes. However, even with the local characteristic decomposition technique, numerical errors could be caused by point-wise FVS methods or the highly nonlinear equation of state of the material.

    38. An innovative open boundary treatment for incompressible SPH

      Sh. Khorasanizade and J. M. M. Sousa

      Article first published online: 3 AUG 2015 | DOI: 10.1002/fld.4074

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      Together with a modified particle shifting algorithm, an innovative inflow/outflow boundary treatment has been tested in truly incompressible smoothed particle hydrodynamics simulations of the flow around a square obstacle in plane channel with open outflow. A detailed study of the selected benchmark problem has been conducted up to a Reynolds number of 625, and extensive comparisons with reference data were carried out. The results have demonstrated that the proposed improvements lead to increased robustness and accuracy of the SPH method.

    39. A meshless method for numerical simulation of depth-averaged turbulence flows using a k-ϵ model

      Yasser Alhuri, Fayssal Benkhaldoun, Driss Ouazar, Mohammed Seaid and Ahmed Taik

      Article first published online: 3 AUG 2015 | DOI: 10.1002/fld.4067

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      These are velocity fields at different times for tidal waves in the Strait of Gibraltar using the turbulent shallow water flow conditions. The results are displayed for the semidiurnal M2, S2, and N2 tidal waves as well as the diurnal K1 tidal wave. Using the tidal conditions, the flow exhibits a recirculating zone with different orders of magnitudes near the Caraminal Sill (interface separating the Atlantic Ocean and Mediterranean Sea). These results demonstrate the capabilities of the proposed meshless method to solve turbulent shallow water flows in irregular domains with complex topography.

    40. Backward uncertainty propagation in shape optimization

      Bijan Mohammadi

      Article first published online: 31 JUL 2015 | DOI: 10.1002/fld.4077

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      We investigate the impact of state uncertainties in shape optimization to provide the covariance matrix of the optimal shape. The approach is enough efficient to be applied directly during adjoint-based designs of full aircrafts.

    41. Efficient multigrid preconditioners for atmospheric flow simulations at high aspect ratio

      Andreas Dedner, Eike Müller and Robert Scheichl

      Article first published online: 28 JUL 2015 | DOI: 10.1002/fld.4072

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      Many problems in fluid modelling require the efficient solution of highly anisotropic elliptic partial differential equations (PDEs) in "flat" domains. We describe an algorithmically optimal tensor-product geometric multigrid preconditioner for the pressure correction equation in global atmospheric flow models and proof the convergence of the algorithm analytically. We discuss an efficient and massively parallel implementation on a tensor product grid representing a thin spherical shell and demonstrate the performance and scalability of the solver for different atmospheric model problems.

    42. A refined r-factor algorithm for TVD schemes on arbitrary unstructured meshes

      Di Zhang, Chunbo Jiang, Liang Cheng and Dongfang Liang

      Article first published online: 27 JUL 2015 | DOI: 10.1002/fld.4073

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      The key findings:

      1. Several existing r-factor algorithms available in the literature are reviewed in detail for extending TVD schemes to arbitrary unstructured grids, and the respective advantages and disadvantages of these algorithms are also revealed and analyzed.
      2. A refined r-factor algorithm (FFISAM) is proposed based on the review. The FFISAM is designed to overcome several inherent drawbacks of the existing algorithms while preserve their attractive attributes. Numerical results show that the FFISAM leads to a better performance in terms of accuracy and convergence.
    43. Numerical simulations of bouncing jets

      Andrea Bonito, Jean-Luc Guermond and Sanghyun Lee

      Article first published online: 24 JUL 2015 | DOI: 10.1002/fld.4071

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      We investigate numerically fascinating bouncing jet phenomenon. Left: Laboratory Experiment of the Kaye effect taken at the High Speed Fluid Imaging Laboratory of S. Thoroddsen at King Abdullah University of Science and Technology. Right: Numerical simulation of the Kaye effect using our adaptive finite element method.

    44. Front-tracking by the level-set and the volume penalization methods in a two-phase microfluidic network

      Johana Pinilla, Charles-Henri Bruneau and Sandra Tancogne

      Article first published online: 21 JUL 2015 | DOI: 10.1002/fld.4069

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      A technique for simulating a two-phase Newtonian/viscoelastic flow in a micro-channels network is proposed. This technique involves a level-set approach for tracking the interface between the two fluids, a penalization method for dealing with the geometry, a numerical contact angle model based on the Cox relation and the Oldroyd-B model for modeling the viscoelastic fluid.


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