ACCELERATION HEAD IN CENTRIFUGAL PUMPS A042
Start a centrifugal pump with the discharge valve open and the fluid can accelerate fast enough in the suction line to drop the pressure and cause the fluid to vaporize.
- Pumps equipped with quick opening discharge regulating valves have this problem.
- You might also trip a circuit breaker if the amps. come up too quick
To calculate the head loss due to uniform acceleration use this equation:
ha = Head required to accelerate the fluid in the suction piping (feet or meters.)
L = Length of the suction line (feet or meters).
V2 = The final velocity of pumpage, feet/sec. or meters/sec.
V1 = The initial velocity of pumpage, feet/sec. or meters/ sec.
g = Acceleration of gravity (32.2 feet/sec2 0r 9,8 meters/sec2
t = time increments that pumpage accelerates from V1 to V2, seconds.