Category:CDm 1.Introduction

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The numerical solution of convection-diffusion transport problems arises in many important applications in science and engineering. These problems occur in many applications such as in the transport of air and ground water pollutants, oil reservoir flow, in the modeling of semiconductors, and so forth. This paper describes the Convection Diffusion Applications for solving this equation.

In the context of mass difussion within a fluid, (1) is is the mass conservation equation and (2) is a contitutive law proposed by Fourier. The notation is standard: $ρ$ is the density, $C$ the heat capacity, $κ$ the thermal conductivity, $T$ is the temperature, $v$ is the velocity field and $q$ is the diffusive flux per unit fluid density.

Remark: systen can be decoupled since we can plug (2) into (1) and solve the scalar equation

$\rho C \frac{\partial T}{\partial t} + \rho Cv \cdot \nabla T - \nabla \cdot (\kappa \nabla \cdot T) = 0$ (3)

Problem statement

Let us consider the transport by convection and diffusion in an open set $Ω$ $\subset \Re^d$ (d=2 or 3) \ with piecewise smooth boundary $Γ$ , such that $\Gamma = \Gamma_d \cup \Gamma_N$ . The unit outward normal vector to $Γ$ is denoted $n$ . The convection-diffusion initial-boundary value problem can be stated as follows: given a divergence-free velocity field a, the diffusion tensor $κ$ and adequate initial and boundary conditions, find $T$ : $\bar{\Omega} \times \left[ 0, T \left] \rightarrow \Re \right. \right.$ such that