Drag of a moving body
 

Hello member,

I would like to ask you one advice. Consider a moving body at velocity V that experiences a drag force. This body (called now BODY) is modeled as an empty space inside a portion of domain (called now DOMAIN). In order to determine the drag:

1) The first way is to impose an inlet velocity V upstream of the body. This way is ok.

But, if I want to use different ways, for example the followings, what you would suggest? Are they good and right?

2) The body is fixed, the inlet velocity is zero, and at the BODY's walls I impose both a no-slip condition and also a velocity V, that can be done in the wall boundary condition panel.
3) Using a sliding mesh approach, where I impose at the mesh of the DOMAIN the translational velocity V (the body is practically an empty space inside this moving sliding mesh).
4) Imposing a translational velocity at the DOMAIN using a moving reference frame (translational velocity V).

What do you suggest? Are they equivalent methods to obtain the Drag?

Thank you very much