How to calculate power using water jet (40 bar)?

[yie]

I have some problem about how to calculate power for my system. i use water jet as prime mover to move the turbine. Here i give the spec of my system :-

Water Jet spec
1. Operation pressure = 40 bar
2. Suction Volume = 17litre/minutes

We know that to calculate power is equal H(head) x flow rate x g x Efficiency...But for my system i don,t know the best way to calculate power. If i used this spec to calculate power, the result that i get is to small. So hope you can help me to simplify this problem. Thank you.

 

[motoplex]

If efficiency = 100 % the theoretical outcome is :

Power = Volume flow x Pressure difference

Note units :

Power in Watt or Joule/s
Volume flow in m^3/s
Pressure difference in Pa or N/m^2

Gr.
Sander