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-   -   Staggered Vs Collocated grid (http://www.cfd-online.com/Forums/main/13656-staggered-vs-collocated-grid.html)

 Sas June 15, 2007 11:23

Staggered Vs Collocated grid

Dear all, Is it possible to use QUICKEST schemme for advection on collocated grid ? Have you ever been used that on any non-staggered grid? I am having problems of mass conservation if I use this scheme on collocated grid. Any help will be highly appreciated. Thank you !! Sas

 jinwon June 15, 2007 11:38

Re: Staggered Vs Collocated grid

Based on my experiences, I can remind that the collocated grids is primarily used in the compressible flow. On the other hand, most incompressible flow is discretized by a staggered grid.

 Sas June 15, 2007 12:20

Re: Staggered Vs Collocated grid

Thank you for the response. But I asked about the scheme. I am taking about Advection terms, which I plan to solve using QUICKEST method. So I wanted to know if someone has ever used QUICKEST scheme on collocated grid? I try to use that on collocated, but there was a problem of mass conservation.

 otd June 15, 2007 12:25

Re: Staggered Vs Collocated grid

Rhie and Chow (1983, AIAA J. 21, 1525)

They use both staggered and colocated, interpolating as needed. Used widely since its publication.

 ds June 17, 2007 12:19

Re: Staggered Vs Collocated grid

ya you can apply quick scheme on collocated grid , for mass conservation you should use Rhie and Chow realtion to find the face velocities as suggested by otd.

 skg June 21, 2007 08:04

Re: Staggered Vs Collocated grid

I have used QUICK in case of collocated grid for discretization of advection terms. I have also used QUICK in case of staggered grid in cylindrical coordinate system. Regarding this you can consult the book of "Ferziger & Peric". But, I was unable to use the QUICK scheme in unstructured i.e. triangular grid. Can any one give any idea or any paper of implementation of QUICK in case of unstructured grid? Thanks.

 Sas June 21, 2007 11:34

Re: Staggered Vs Collocated grid

Dear Skg, I wonder in collocated grid all the varibales are at ONE point/node. But in QUICK, we need to calculate flux at the sides of the element/cell. For example, we can take concentration in the centre and velocity on the sides of the cell and then we can calculate flux. But if we take concentration as well velocities in the centre of the cell, the Did you encountered mass conservation error. Please eloborate.. Thanks.. Sas

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