[boffin5]

Since I have been working with OpenFOAM for a while, I should understand this question. But it seems I don't.

Regarding the motorbike tutorial, when I run it and then view the results in paraView, in the Mesh Regions, I only visualize the motorbike and the ground. In other words, I un-check the internal mesh.

In the boundary conditions for U, the motorBikeGroup is set to noSlip, and the lowerWall is set to fixedValue, internalField.

My understanding of boundary layer flow is that adjacent to the surface, the velocity is zero for a noSlip condition. So in paraView, when viewing the results for U, I expect to see the motorBike colored blue, indicating zero flow velocity, and the ground colored according to the flow velocity.

But, as can be seen in the attached image, there is color variation on the motorBike as if the flow was moving along the surface; for example, the flow speeds up over curved areas. But with noSlip, shouldn't it be zero all along the motorBike surfaces?

I'm sure there is a simple answer that I am missing, but I would love to see see it.

[matejfor]

Do not worry, it is a ParaView thing. The way how the values are represented. At the top, second Toolbar - you may select a variable to plot. Typically there are two velocities. One with an orange cube. Those are raw data - cell centered. The other ones with an orange dot are interpolated values. Raw data will show velocity calculated by wall function thus it is not zero. Hope it helps.

[boffin5]

Thanks for your reply! I looked at both of your suggested approaches, but still don't see a graphical depiction of zero U at the wall in paraView. This bothers me, as I thought I saw an Air Shaper video that showed what I am looking for.