Why at end of the simulation we see a pressure jump see seco

Why at end of the simulation, we see a pressure jump (see second figure)? How do you think we can fix this issue not to damage the equipment?

Solution

From the figure it is not clear what type of pump you have simulated. I persume it is a positive displacement pump since at the end of the stroke of actuator the pressure is building up.

This can be overcome by installing a variable displacement pump instead of the positive displacement pump or installing a pressure relief valve in the pipe line so that when the pressure exceeds a value ( the pressure relief can be adjusted ) it opens and allows the fluid to goback to the reservoir.