Diffusion term

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Discretisation of Diffusive Term

1. Approximation Schemes for diffusive term
2. Approximation of Diffusive Fluxes
3. Discretisation on orthogonal grids
4. Discretisation on non-orthogonal curvilinear body-fitted grids

1. Description

A control volume in mesh is made up of set of faces enclosing it. The figure 1.1 shows a typical situation. Where A represent the magnitude of area of the face. And n represents the normal unit vector of the face under consideration.

Figure 1.1

and are position vector of centroids of cells cell 0 and cell 1 respectively.

2. Approach 1

We define vector