Simulation of impacts of fluid free surfaces with solid boundaries

Abstract

SUMMARYDeficiencies associated with the simulation of impacts of fluid free surfaces with solid boundaries by use of marker-and-cell methods are identified and addressed. New procedures are introduced that affect the movement of markers in cells adjacent to a solid boundary, the flags of the cells that comprise a solid boundary and the pressure boundary condition for a cell in which impact occurs. Combined with fundamental changes in the sequence of steps in the computational cycle, these new procedures allow the intentional treatment of impact. As a result, improved estimates are obtained of the pressure associated with the cells adjacent to a boundary along which impact occurs. Consequently, more appropriate adjustments are made of the tentative internal velocities associated with such cells. In addition, a special procedure is presented for the adjustment of the tentative internal velocity between two surface cells. Finally, a new cell type termed a comer cell is defined and a procedure for its treatment is presented. Numerical examples are included to illustrate the previous deficiencies associated with the simulation o l impact as well as the effectiveness of the new methods presented in this paper. Validation of the new methods is achieved by comparison with experimental results for spillage over a containment dike.

Large Eddy Simulation of Turbulent Channel Flow Using Algebraic Wall Model

“…The coupling between continuity equation and pressure fields is performed by the simplified markerand-cell (SMAC) method [23]. Poisson equation is solved iteratively by Incomplete Cholesky Decomposition Conjugated Gradient method.…”

Large Eddy Simulation of Turbulent Channel Flow at Reτ = 590

“…The coupling between continuity equation and pressure fields is performed by the simplified marker-and-cell (SMAC) method [15]. Poisson equation is solved iteratively by a Preconditioned Incomplete Cholesky Decomposition Conjugated Gradient method.…”

The three-dimensional Eulerian–Lagrangian marker and micro cell method for the simulation of free surface flows

“…(20) into Eq. (21) is presented in detail in Johnson et al [18]. In the ELMMC method, two types of pressure boundary conditions can be imposed by the use of initial settings for an outlet region, namely, open and continuing domain.…”

“…The new Eulerian-Lagrangian marker and micro cell (ELMMC) method [5] is based on the work of Raad et al [31], Chen et al [8,9], Johnson et al [18], and Fadda et al [12]. In the ELMMC method, the free surface is tracked by the use of unconnected massless, ''floating'', Lagrangian markers, named surface markers, while the flow field is calculated in a fixed, Eulerian system discretized with rectangular computational cells.…”