In deep drawing simulation with shell model, is clearance between die and punch required?

Tsega

I am performing a deep drawing simulation on Hyperform Radioss Incremental with shell (surface) models of the components. I have assigned a blank thickness of 2.5 mm.

What I need to know is that whether or not Die-Punch Clearance is required in the shell model as if it is like solid model.

Thanks in advance!

Tsega

In addition, I don't want all the blank to be drawn into the die cavity (I need some flange). I tried to apply a fixed free edge constraint but it doesn't seem working.

Any kind of assistance would be appreciated.