Stop time for a pump after an electrical shut down 1

[Xalii]

I have read a few treads about this but I am not yet clear on the following subject:
For a simple water system (1 pump with an electrical motor, 1 check valve, 1 pipe delivering in 1 tank) is there a formula to calculate the time needed by the pump to stop assuming that we have :
RPM: initial rotation
I: inertia of the pump+motor
L: length of the pipe
Q: flow
and what is the curve looking like ? rather linear?

According to my understanding this information is very important to know if the surge might create cavitation/collapse in a high oint in the pipeline.
I have asked my pump seller to give me this information but he was very evasive...

 

[Xalii]

Dear Lyle,

I guess with a short steel pipe, your assumption is valid, which is not my case however, the equations are quite close as you are calculating losses in the system and I should calculate the one of the pump. Cam you share the "standard solution" so see if they could be applicable in my case ?

Best regards

 

[PersonalProfile]

I had a look through my records and although I can find my enquiry I sent the mathematicians, I cannot find their response - apologies.

If it is really important, I could try to find their contact details and you could contact them for yourself [though if they are willing to assist, they may not do it pro bono].

Regards,
Lyle

 

[Xalii]

Thanks for this Lyle, but I will try to check (when I am back home, in a month time) with the university were I have studied as they are specialized in hydraulic machines.
Best regards