Learning Forum

[Laurens]

Hi ansys community,

I'm doing a simulation incorporating the prescribed motion of the wall and boundary conditions. The prescribed motion shows the filling of a heart chamber, meaning that there are no stationary points in the wall, inlet or outlet. Both the boundary conditions and the wall is discribed by an UDF file, which seems to be working fine.

The problem I have is that there are always 2 points lingering during the movement of the wall and its always at the same location, even if I import a new geometry with a new prescribed motion. Good to know

My procedure: 

1. Compile and load udf
2. Activate dynamic mesh
3. Select smoothing (spring) and remeshing (unified remeshing)
4. Select user defined for inlet, outlet and wall (all the same functions describing the complete wall movement but seperated by name)

For the rest I do not set anything. I tried changing the wall to moving wall in zone definition + testing out different time steps and mesh sizes. 

Is there something specific I have to set when I want all the boundary nodes to move without any stationary points?

Kind regards

[Essence]

Hello,

While creating named selections, you might have missed those two points to be included in the geometry creation. It can happen when the part is small. Please try checking that.