International Journal for Numerical Methods in Fluids

Cover image for Vol. 72 Issue 1

10 May 2013

Volume 72, Issue 1

Pages 1–134

  1. Research Articles

    1. Top of page
    2. Research Articles
    1. Parallel fully implicit two-grid methods for distributed control of unsteady incompressible flows (pages 1–21)

      Haijian Yang and Xiao-Chuan Cai

      Version of Record online: 7 SEP 2012 | DOI: 10.1002/fld.3729

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      We introduce and study some fully coupled parallel two-grid Lagrange-Newton-Krylov-Schwarz algorithms for the suboptimal distributed control of unsteady incompressible flows governed by the Navier-Stokes equations.

    2. 3D staggered Lagrangian hydrodynamics scheme with cell-centered Riemann solver-based artificial viscosity (pages 22–42)

      Raphaël Loubère, Pierre-Henri Maire and Pavel Váchal

      Version of Record online: 27 SEP 2012 | DOI: 10.1002/fld.3730

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      This paper proposes the development in 3D of a staggered Lagrangian hydrodynamics simulation code by means of an artificial viscosity force using a cell-centered approximate Riemann solver coupled with a piece-wise linear velocity field reconstruction and its associated frame-invariant limiter.

    3. A high-order accurate discontinuous Galerkin finite element method for laminar low Mach number flows (pages 43–68)

      A. Nigro, S. Renda, C. De Bartolo, R. Hartmann and F. Bassi

      Version of Record online: 1 OCT 2012 | DOI: 10.1002/fld.3732

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      A DG method designed to improve the performance of steady and unsteady laminar flow simulations at low Mach numbers is proposed. The figure shows the influence on the accuracy of the following: (i) high-order discretization (top row: flat plate, u-velocity component), (ii) grid topology (middle row: NACA0012 airfoil, contours of normalized pressure), for steady-state computations, and of the (iii) flux preconditioning approach for unsteady flow simulations (bottom row: vortex shedding behind a circular cylinder, snapshots of normalized pressure).

    4. Efficiency and scalability of a two-level Schwarz algorithm for incompressible and compressible flows (pages 69–89)

      H. Alcin, B. Koobus, O. Allain and A. Dervieux

      Version of Record online: 24 OCT 2012 | DOI: 10.1002/fld.3733

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      Deflation and balancing-decomposition methods built on coarse-grid bases are studied. They are combined with an additive Schwarz domain decomposition method. Application to a compressible flow calculation shows a factor two reduction in CPU.

    5. Control of hydrothermal waves in a thermocapillary flow using a gradient-based control strategy (pages 90–118)

      Frank Muldoon

      Version of Record online: 1 OCT 2012 | DOI: 10.1002/fld.3735

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      Control of the hydrothermal waves in a thermocapillary flow is addressed using a gradient-based control strategy and a spatially and temporally varying heat flux boundary condition at the free surface. The modeled problem is the ‘open boat’ process of crystal growth, the flow which is driven by Marangoni and buoyancy effects. Almost complete suppression of the hydrothermal waves is obtained for certain choices of the control algorithm parameters.

    6. On the characterization of grid density in grid refinement studies for discretization error estimation (pages 119–134)

      L. Eça, M. Hoekstra, J. F. Beja Pedro and J. A. C. Falcão de Campos

      Version of Record online: 8 OCT 2012 | DOI: 10.1002/fld.3737

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      Numerical error estimation based on systematic grid refinement requires the characterization of the density of each grid by a single parameter (typical cell size). Nominally, this is possible only if the family of grids is geometrically similar, which would essentially rule out the application of this kind of error estimation to unstructured grids. This paper shows that meaningful error estimation is possible also when geometrical similarity is not obeyed, even though the order of grid convergence may not be reliable.