Hi Stressers
If I add constant force F1 in -Y at free end of discharge pipe. does first +y restrain before free end sense of this force?
In other word, I question about constant force if it react only on the node I put it or it transfer to other related nodes ?

This can be easily understood by the example of a cantilever (fixed at one end and free at other).

What happens with forces & moments at the fixed end of cantilever when a vertical force is applied at the free end?

in my case they are in the same vertical axe so I think the force should transfer to first +y restrain with out any moment but when I run the system in Caesar the force on restrain in Y direction is about -1650 N while the reaction force from PSV is -8000 N . I tried to put it once in free end node and once in Restrain node and I get the same result in two cases. I think the restrain force in Y direction should at least equal -8000 N . is that right??

The system as a whole must be in equilibrium. 100% of the applied load does not necessarily transfer to the nearest support. The applied loads are numerically distributed to the supports based on the relative stiffness of the pipe and the supports.