Mowat, A.G.B.Van den Bergh, Wilhelm JohannMalan, A.G.Wilke, Daniel Nicolas2016-07-222016-07-222016-05Andrew Gavin Bradford Mowat, Wilhelm Johann van den Bergh, Arnaud George Malan, Daniel Wilke, (2016) "An AMG strategy for efficient solution of free-surface flows", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 26 Iss: 3/4, pp.1172 - 1186.0961-5539 (print)1758-6585 (online)10.1108/HFF-09-2015-0389http://hdl.handle.net/2263/56018PURPOSE : An area of great interest in current computational fluid dynamics research is that of free-surface modelling (FSM). Semi-implicit pressure-based FSM flow solvers typically involve the solution of a pressure correction equation. The latter being computationally intensive, the purpose of this paper is to involve the implementation and enhancement of an algebraic multigrid (AMG) method for its solution. DESIGN / METHODOLOGY / APPROACH : All AMG components were implemented via object-oriented C++ in a manner which ensures linear computational scalability and matrix-free storage. The developed technology was evaluated in two- and three-dimensions via application to a dam-break test case. FINDINGS : AMG performance was assessed via comparison of CPU cost to that of several other competitive sparse solvers. The standard AMG implementation proved inferior to other methods in three-dimensions, while the developed Freeze version achieved significant speed-ups and proved to be superior throughout. ORIGINALITY / VALUE : A so-called Freeze method was developed to address the computational overhead resulting from the dynamically changing coefficient matrix. The latter involves periodic AMG setup steps in a manner that results in a robust and efficient black-box solver.en© Emerald Group Publishing Limited.Matrix-freePressure-poissonFree-surface modelling (FSM)Algebraic multigrid (AMG)Engineering, built environment and information technology articles SDG-09SDG-09: Industry, innovation and infrastructurePostprint Article