Learning Forum

[pgalves]

I have a simple 2D model of flow in a pipe (50mm length) where a spherical particle (0.5mm diameter) is placed near the inlet (2mm height), as shown in the figure below. I want the particle to move due to the flow. The flow velocity is imposed at the inlet. I'm using a transient, pressure-based solver. I want the movement of the particle to affect the flow, so I'm using dynamic mesh to simulate the particle motion.

[Rob]

How does the mesh look in the first few time steps. That looks like it's smoothing but not remeshing the tri region. n

[pgalves]

How does the mesh look in the first few time steps. That looks like it's smoothing but not remeshing the tri region./forum/discussion/comment/99568#Comment_99568

Looks like it's pulling the mesh, just like the picture I attached. Yes, it is surely not remeshing, but why? I have the remeshing option enabled. I have started over with a simpler geometry and mesh and I get the same problem...n

[Rob]

If you turn off smoothing what happens? Look at what triggers remeshing, if smoothing masks an issue until it's too late that could be a factor. n

[pgalves]

Thanks Rob,nWhen I turn off Smoothing the mesh looks like this (figure). This is a new model, with just a rectangle and a circle.nIt seems like the Particle boundary is 'glued' to the mesh elements of the fluid. nCould it be a problem with the model's geometry? Is it not enough to define a circle inside the rectangle (pipe) ?n

[Rob]

The circle is fine, it looks like the trigger for remeshing isn't working. Check the cell min/max size and compare against the cell size in your model. As you've used the 6DOF remeshing set up from the tutorials don't see what else it can be. n

[disha]

@pgalves, did you able to solve that stretching issue instead of remeshing itself .please tell me as i am trying to do the same and i am stuck at this .i cant go for MACROs or UDF as i dont know C. thank you in advance!n

[YasserSelima]

nThe UDF manual has appendix that would help you write your first UDF. Also you can look at the examples provided and do it step by step. Good Luck!n