# Diffusion term

(Difference between revisions)
 Revision as of 22:40, 14 September 2005 (view source)Zxaar (Talk | contribs)← Older edit Revision as of 22:41, 14 September 2005 (view source)Zxaar (Talk | contribs) Newer edit → Line 1: Line 1: ==Discretisation of Diffusive Term == ==Discretisation of Diffusive Term == + === Sub-topics === + ---- # [[Approximation Schemes for diffusive term]] # [[Approximation Schemes for diffusive term]] # [[Approximation of Diffusive Fluxes]] # [[Approximation of Diffusive Fluxes]] # [[Discretisation on orthogonal grids]] # [[Discretisation on orthogonal grids]] # [[Discretisation on non-orthogonal curvilinear body-fitted grids]] # [[Discretisation on non-orthogonal curvilinear body-fitted grids]] - + ---- ===1. Description=== ===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. 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.

## Discretisation of Diffusive Term

### 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

$\vec r_{0}$ and $\vec r_{1}$ are position vector of centroids of cells cell 0 and cell 1 respectively.

${\rm{d\vec s}} = \vec r_{1} - \vec r_{0}$

### 2. Approach 1

We define vector $\vec \alpha {\rm{ = }}\frac{{{\rm{\vec A}}}}{{{\rm{\vec A}} \bullet {\rm{d\vec s}}}}$