Diffusion term
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[[Image:Nm_descretisation_diffusionterms_01.jpg]] <br> | [[Image:Nm_descretisation_diffusionterms_01.jpg]] <br> | ||
'''Figure 1.1''' <br> | '''Figure 1.1''' <br> | ||
| - | <math> \vec r_{0} </math> and <math> \vec r_{1} </math> are position vector of centroids of cells cell 0 and cell 1 respectively. <br> | + | :<math> \vec r_{0} </math> and <math> \vec r_{1} </math> are position vector of centroids of cells cell 0 and cell 1 respectively. <br> |
<math> {\rm{d\vec s}} = \vec r_{1} - \vec r_{0} </math> | <math> {\rm{d\vec s}} = \vec r_{1} - \vec r_{0} </math> | ||
| + | |||
| + | <br> | ||
| + | |||
| + | ===2. Approach 1 === | ||
| + | We define vector | ||
| + | <math> | ||
| + | \vec \alpha {\rm{ = }}\frac{{{\rm{\vec A}}}}{{{\rm{\vec A}} \bullet {\rm{d\vec s}}}} | ||
| + | </math> | ||
Revision as of 22:36, 14 September 2005
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
and 
are position vector of centroids of cells cell 0 and cell 1 respectively.
2. Approach 1
We define vector
