Hello Akshay Maniyar,

thank you for your reply.

The loadsteps are similar to the Ansys How To Video you have send me.

The first loadstep is just the interference fit without any external load. I have applied a frictional contact where the interference of shaft and hub lays. On the second load step a displacement of 5 mm is applied so that the hub is pulled away from the shaft (external displacement "A"). The shaft is fixed on one side (External displacement "B") on both steps. 

External displacement B:

External Displacement A: 

The force reaction graph in the post is from the displacement "A"