Zifei Meng¹, Pengnan Sun^1,*, Yang Xu¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.31, No.1, pp. 1-1, 2024, DOI:10.32604/icces.2024.011674

Abstract DNS simulations on incompressible flows with high Reynolds number using meshfree methods remain an enduring challenge to be addressed. In the present work, we attempt to use a high-order SPH scheme (TENO-SPH) to make DNS simulations on high Reynolds number flows. To investigate this, several spatial reconstructions are applied under the Riemann-ALE-SPH framework, and their performances are compared. Particularly, the accuracy of SPH is significantly enhanced by WENO and TENO reconstructions. For free surface flows, we implement a Lagrangian TENO-SPH to reproduce these flows at different Reynolds numbers. More importantly, to make DNS simulations, the More >

D.-A. An-Vo, N. Mai-Duy, T. Tran-Cong

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.3, pp. 87-88, 2011, DOI:10.3970/icces.2011.016.087

Abstract In this paper, we develop a control-volume technique based on 2-node integrated-radial-basis-function elements (IRBFEs) for the numerical solution of steady incompressible flows governed by the stream function-vorticity formulation. The fluid domain is discretised by a Cartesian grid from which non-overlapping rectangular control- volumes are formed. Line integrals arising from the integration of the diffusion and convection terms over control volumes are evaluated using the middle-point rule. The convection term is effectively treated by the upwind scheme with deferred correction strategy. Instead of using conventional low-order polynomials, all physical quantities at the interfaces are presently estimated More >

Alfredo Nicolás¹, Blanca Bermúdez²

CMES-Computer Modeling in Engineering & Sciences, Vol.82, No.3&4, pp. 163-178, 2011, DOI:10.32604/cmes.2011.082.163

Abstract Mixed convection viscous incompressible fluid flows, under a gravitational system, in rectangular cavities are reported using the unsteady Boussinessq approximation in velocity-vorticity variables. The results are obtained using a numerical method based on a fixed point iterative process to solve the nonlinear elliptic system that results after time discretization; the iterative process leads to the solution of uncoupled, well-conditioned, symmetric linear elliptic problems for which efficient solvers exist regardless of the space discretization. Results with different aspect ratios A up to Grashof numbers Gr = 100000 and Reynolds numbers Re = 1000 for the lid driven More >

Elsa Báez, Alfredo Nicolás¹

CMES-Computer Modeling in Engineering & Sciences, Vol.41, No.2, pp. 107-130, 2009, DOI:10.3970/cmes.2009.041.107

Abstract The unsteady Navier-Stokes equations in primitive variables that govern viscous incompressible fluid flow are numerically solved by a simple projection method which involves an operator splitting technique of three steps in the time discretization process. The numerical scheme does not involve any iteration, is independent of the spatial dimension, and its costly part relies on the solution of elliptic problems for which very efficient solvers exist regardless of the spatial discretization. The scheme is tested with the well known two-dimensional lid-driven cavity problem at moderate and high Reynolds numbers Re in the range 400 ≤ Re… More >

Alfredo Nicolás¹, Blanca Bermúdez²

CMES-Computer Modeling in Engineering & Sciences, Vol.20, No.2, pp. 73-84, 2007, DOI:10.3970/cmes.2007.020.073

Abstract 2D viscous incompressible flows are presented from the unsteady Navier-Stokes equations in its velocity-vorticity formulation. The results are obtained using a simple numerical procedure based on a fixed point iterative process to solve the nonlinear elliptic system that results once a second order time discretization is performed. Flows on the un-regularized unit driven cavity problem are reported up to Reynolds numbers Re=4000 to compare them with those reported by other authors, mainly solving the steady problem, and supposed to be correct. Moreover, results are reported for Re = 1000, 4000, 5000, and 10000 to see how More >

H.S. Wijesinghe¹, N.G. Hadjiconstantinou²

CMES-Computer Modeling in Engineering & Sciences, Vol.5, No.6, pp. 515-526, 2004, DOI:10.3970/cmes.2004.005.515

Abstract We present an implicit hybrid atomisticcontinuum formulation for unsteady, viscous, incompressible flows. The coupling procedure is derived from a domain decomposition method known as the Schwarz alternating method. A dilute gas impulsive Couette flow test problem is used to verify the hybridscheme. Finally, a method to reduce computational costs through limited ensemble averaging is presented. The implicit formulation proposed here is expected to be significantly faster than a time explicit approach based on a compressible formulation for the simulation of low speed flows such as those found in micro- and nano–scale devices. More >