[ivan-s]

In flow modelling on COMSOL, there is a boundary condition "internal wall."

When looking at the model through the inlet or outlet at the internal wall with the plot "wall resolution", it is possible to see that the internal wall is transparent. This suggests to me that the wall resolution is not important at this boundary condition.

Is this true or false?

Furthermore, if it is true, is it necessary to add mesh boundary layers there?

Thank you.

Insights into other software would be helpful as well, because these softs probably use the same mathematics.