Available online at www.sciencedirect.com
Mathematics and Computers in Simulation 79 (2009) 3415–3423
Application of mesh-adaptation for pollutant transport by water flow
Fayssal Benkhaldoun
a,∗
, Imad Elmahi
b
, Mohammed Seaïd
c
a
LAGA, Université Paris 13, 99 Av J.B. Clement, 93430 Villetaneuse, France
b
ENSAO, EMCS Complex Universitaire, B.P. 669, 60000 Oujda, Morocco
c
School of Engineering, University of Durham, South Road, DH1 3LE, UK
Received 1 February 2008; received in revised form 10 December 2008; accepted 9 April 2009
Available online 22 April 2009
Abstract
An adaptive finite volume method is proposed for the numerical solution of pollutant transport by water flows. The shallow
water equations with eddy viscosity, bottom friction forces and wind shear stresses are used for modelling the water flow whereas,
a transport-diffusion equation is used for modelling the advection and dispersion of pollutant concentration. The adaptive finite
volume method uses simple centred-type discretization for the source terms, can handle complex topography using unstructured
grids and satisfies the conservation property. The adaptation criteria are based on monitoring the pollutant concentration in the
computational domain during its dispersion process. The emphasis in this paper is on the application of the proposed method for
numerical simulation of pollution dispersion in the Strait of Gibraltar. Results are presented using different tidal conditions and
wind-induced flow fields in the Strait.
© 2009 IMACS. Published by Elsevier B.V. All rights reserved.
Keywords: Water flow; Pollutant transport; Adaptive method; Finite volume method; Unstructured grids
1. Introduction
During the last decades partial differential equations have been used as practical tools to model many environmental
problems from real life. Their have also been used to approximate and predict the dynamics of such problems. The
goal of the present work is to provide a simple and practical numerical model able to resolve and correctly capture
the transport and dispersion of a pollutant by water flows. The underlying equations describe the free-surface flow and
species equations. Here, only water flow and pollutant concentration are coupled and neither chemical reactions nor
heat transfer are considered. The flow is governed by the depth-averaged Navier–Stokes equations involving several
assumptions including (i) the domain is shallow enough to ignore the vertical effects, (ii) the pressure is hydrostatic,
and (iii) viscous dissipation of energy is ignored. A convection–diffusion equation is used to model the distribution of
pollutant concentration on the water free-surface.
The emphasis of the present work is on the application of the developed methods to a pollution dispersion in the
Strait of Gibraltar. The Strait of Gibraltar has been subject of several scientific investigations ranging from meteological
studies to geological researches. Its strategical location makes these investigations indispensable for understanding the
global oceanography and the climate prediction. The Strait is heavily used by shipping and oil transport, being one
∗
Corresponding author. Tel.: +33 1 49 40 36 15; fax: +33 1 49 40 35 68.
E-mail address: fayssal@math.univ-paris13.fr (F. Benkhaldoun).
0378-4754/$36.00 © 2009 IMACS. Published by Elsevier B.V. All rights reserved.
doi:10.1016/j.matcom.2009.04.007