Learning Forum

[Jose Amigo]

Hi everyone,

I'm trying to model a 2D case of a moving fin, which has a prescribed motion given by a udf and the 6DOF method. This “moving fin” moves downwards as time progresses and is treated as a rigid body, as shown in the picture below.


At the left side of the fin, there is a solid region and the rest of the domain is filled with water. I had some questions in relation to the dynamic mesh setup:

- I’ve seen tutorials of falling objects but they usually exclude the interior mesh of the moving objects and instead prescibe a rigid body motion to the object’s boundary. In my case, I’m meshing the interior of the object (moving fins) and prescribing the motion to the interior cells. Does it make any difference if I prescribe a motion to the walls as well?

- Is it possible to have a moving solid object (moving fins) in contact with another stationary solid region (heating bar)? Or do I always need a fluid region in between for the dynamic mesh to work properly?

Any feedback is fully appreaciated.

José

[Federico]

Hello, 

How exactly are you prescribing the motion of the fin? If this fin is moving as a rigid body, then you really only need to set the motion to the walls of the fins, and the interior cells will follow.

For question 2, you will need to create a mesh interface between the fin and the stationary heating bar. This will allow your fin to "slide" along the heating bar.