Commun. Comput. Phys., 16 (2014), pp. 1135-1180.


A Unified Fractional-Step, Artificial Compressibility and Pressure-Projection Formulation for Solving the Incompressible Navier-Stokes Equations

Laszlo Konozsy 1*, Dimitris Drikakis 1

1 Fluid Mechanics and Computational Science, Cranfield University, Cranfield, Bedfordshire, MK43 0AL, United Kingdom.

Received 24 July 2013; Accepted (in revised version) 8 May 2014
Available online 29 August 2014
doi:10.4208/cicp.240713.080514a

Abstract

This paper introduces a unified concept and algorithm for the fractional-step (FS), artificial compressibility (AC) and pressure-projection (PP) methods for solving the incompressible Navier-Stokes equations. The proposed FSAC-PP approach falls into the group of pseudo-time splitting high-resolution methods incorporating the characteristics-based (CB) Godunov-type treatment of convective terms with PP methods. Due to the fact that the CB Godunov-type methods are applicable directly to the hyperbolic AC formulation and not to the elliptical FS-PP (split) methods, thus the straightforward coupling of CB Godunov-type schemes with PP methods is not possible. Therefore, the proposed FSAC-PP approach unifies the fully-explicit AC and semi-implicit FS-PP methods of Chorin including a PP step in the dual-time stepping procedure to a) overcome the numerical stiffness of the classical AC approach at (very) low and moderate Reynolds numbers, b) incorporate the accuracy and convergence properties of CB Godunov-type schemes with PP methods, and c) further improve the stability and efficiency of the AC method for steady and unsteady flow problems. The FSAC-PP method has also been coupled with a non-linear, full-multigrid and full-approximation storage (FMG-FAS) technique to further increase the efficiency of the solution. For validating the proposed FSAC-PP method, computational examples are presented for benchmark problems. The overall results show that the unified FSAC-PP approach is an efficient algorithm for solving incompressible flow problems.

AMS subject classifications: 76D05, 65M08, 65B99, 65Y20

Notice: Undefined variable: pac in /var/www/html/readabs.php on line 165
Key words: Navier-Stokes equations, characteristics-based Godunov-type scheme, unified method.

*Corresponding author.
Email: laszlo.konozsy@cranfield.ac.uk (L. Konozsy), d.drikakis@cranfield.ac.uk (D. Drikakis)
 

The Global Science Journal