[joaquindelpino]

Hello everyone.

I'm simulating a bio-filter inside of a room.
To generate mesh I used snappyHexMesh. Then I runed the simulation using simpleFoam and I got the velocity and pressure in each cell, but now I need to compute the volume of each cell to calculate the % of volume in that velocity is different from zero.

I read a lot of topics in CFD but i don't understand where I must be create codes or use mesh.V().

I would appreciate a detailed explanation

Regards.

Joaquin Del Pino

[Flowkersma]

Hi Joaquin,

Can you use ParaView (paraFoam)?

Following filters in ParaView should do what you want:
1. Use Calculator filter to calculate the scalar of interest (mag(U)).
2. Use Clip filter to extract the volume of interest. Choose ClipType=Scalar, Scalars=magU and choose a delimit value for the velocity.
3. Use IntegrateVariables filter to calculate the volume. Choose attribute=Cell Data and then you should see a column with volume.

Best,
Mikko

[joaquindelpino]

Originally Posted by Flowkersma

Hi Joaquin,

Can you use ParaView (paraFoam)?

Following filters in ParaView should do what you want:
1. Use Calculator filter to calculate the scalar of interest (mag(U)).
2. Use Clip filter to extract the volume of interest. Choose ClipType=Scalar, Scalars=magU and choose a delimit value for the velocity.
3. Use IntegrateVariables filter to calculate the volume. Choose attribute=Cell Data and then you should see a column with volume.

Best,
Mikko

Thx Mikko, I really appreciate your answer. But I have some questions,

1. In calculator filter, I have 2 options, scalar and volume. In scalar appears: p, U_x, U_y, U_z. In vectors appears: U. Wich one I need? ((U_X)^2)+((U_Y)^2)+((U_Z)^2)^(1/2) ? That's correct?

2. In calculator filter mag(U) is the result array name?

3. In the delimit value for the velocity, I need the volume of cells in wich velocity is greater than 0.0001, this is my delimit value?

4. In integrateVariables filter show only one cell data, that's right?
Regards.

[Flowkersma]

Hi Joaquin,

1. and 2. In Calculator you can specify the result array name. By default it is "Result". In the next field you define your function which is for velocity magnitude either "mag(U)" or "((U_X)^2)+((U_Y)^2)+((U_Z)^2)^(1/2)". Change the "Attribute Mode" to "Cell Data" if you want to extract only the cells. If you want a "smooth" surface at the interface then use "Point Data". ParaView will then automatically create a smooth interface with refined mesh and interpolated data.

3. and 4. that is right.

[joaquindelpino]

Ok, thank you for all your replies, there are very helpful.

Regards