how to handle a small gap between stem and valve house
 

Hi All,

Could you help with this one?

The gas flows between the stem and valve house and there is also a small gap between the stem and the valve house(.001 to .003), which allow the stem move up and down. How to handle this small gap when conduct CFD? See the attached. Thanks.

Quite curious about the significance of this small gap in terms of the flow domain..? If that is just a manufacturing limitation which is accurately modeled in 3D i.e. an accurate practical representation (since in reality there can not be an ideal fit), then the model could simply be simulated without this small gap... Also, please do elaborate 'handle' as well, do you mean the meshing? or physics? ...