[chenyfan]

Hi all,

I am working with Foam-extend 3.2.

Following the interIbFoam tutorial case named "cylBumpInterIbFoam", I changed the setField file to set a low water level so that the truncated cylinder (immersed boundary) is partially submerged at the beginning. I would expect that the water in the computational domain is still. However, there is always some disturbance on the immersed boundary close to the interface between the water and air (please see the attached picture). And it seems that it does not satisfy the mass conservation around the partially submerged immersed boundary (because the water level increased during the simulation). Since the original tutorial case works properly (the truncated cylinder is fully submerged in the air at the beginning), so I set a high water level to make the cylinder fully submerged in the water, and the water kept still as expected.


The link of the picture is https://www.dropbox.com/s/yd8c01hvur...bFoam.jpg?dl=0

Could everyone let me know what the problem is and how to solve it? Thanks for your time in advance.

Regards,
Fan