Why does U_{LB} depend physical dimensionality of problemy at LBM??

Palabos General
#1

Hi community,

I have a question about of U_ {LB} at palabos. I simulated a channel 2D (D2Q9) and 3D (D3Q27), where the initial velocity initial is zero, and I used a model with external force term. At the case 2D, my simulation woked with U_ {LB} 0.02, but at the case 3D this value does not work. I changed this value for 0.3.

The choice of these values ​​was to see the examples of the website of Palabos.

But at this moment I still can not explain why it is necessary to make that change.

Can someone tell me the reason, or where can I find literature about this topic?

Thanks for your help

#2

Hello,

Which examples are you talking about? Usually u_lb=0.3 is too large…

Best regards,
Orestis

#3

Thanks for your time Orestis.

I am doing rectangular channel with external force.

Thanks for your help

#4

I understand that but it is difficult to give an answer without knowing which code you are working on. SInce there is no External force driven rectangular channel in the palabos examples.

Best regards,
Orestis