Unified semi-analytical wall boundary conditions applied to 2-D incompressible SPH

JOURNAL OF COMPUTATIONAL PHYSICS

卷:261

Article

Leroy, A.¹  Violeau, D.¹  Ferrand, M.²  Kassiotis, C.¹ 

[1] Univ Paris Est, St Venant Lab Hydraul, F-78400 Chatou, France

[2] EDF R&D, MFEE, F-78400 Chatou, France

关键词: SPH;    Projection method;    Incompressible;    Boundary conditions;   

DOI  :  10.1016/j.jcp.2013.12.035

来源: Elsevier

【 摘 要 】

This work aims at improving the 2-D incompressible SPH model (ISPH) by adapting it to the unified semi-analytical wall boundary conditions proposed by Ferrand et al. [10]. The ISPH algorithm considered is as proposed by Lind et al. [25], based on the projection method with a divergence-free velocity field and using a stabilising procedure based on particle shifting. However, we consider an extension of this model to Reynolds-Averaged Navier-Stokes equations based on the k-epsilon turbulent closure model, as done in [10]. The discrete SPH operators are modified by the new description of the wall boundary conditions. In particular, a boundary term appears in the Laplacian operator, which makes it possible to accurately impose a von Neumann pressure wall boundary condition that corresponds to impermeability. The shifting and free-surface detection algorithms have also been adapted to the new boundary conditions. Moreover, a new way to compute the wall renormalisation factor in the frame of the unified semi-analytical boundary conditions is proposed in order to decrease the computational time. We present several verifications to the present approach, including a lid-driven cavity, a water column collapsing on a wedge and a periodic schematic fish-pass. Our results are compared to Finite Volumes methods, using Volume of Fluids in the case of free-surface flows. We briefly investigate the convergence of the method and prove its ability to model complex free-surface and turbulent flows. The results are generally improved when compared to a weakly compressible SPH model with the same boundary conditions, especially in terms of pressure prediction. (C) 2014 Elsevier Inc. All rights reserved.

【 授权许可】

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