How to calculate mass moment of inertia

[Sam23881]

I need to calculate the mass moment of inertia for the shaft +water inside an impeller pump. I'm able to gather the data for the moment of inertia of the shaft in solidworks.

How do I take into account the water in the pump? How is the volume of the water used in this calculation? It is constantly moving. Therefore, that is tripping me up a bit.

Thanks

 

[nondimensional]

If I may ask, what is the ultimate idea of calculating the moment of inertia of the water?

 

[electricpete]

Good question / clarification by nondimensional

For op, if the purpose is to simulate acceleration (determine acceleration time), the standard approach I've always seen is to consider only the inertia of the rotating element (not the fluid). The interaction between the rotating element and the fluid is typically captured in a torque vs speed curve for the pump (which in turn carries some assumptions about fluid system lineup).

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(2B)+(2B)' ?

 

[PersonalProfile]

The following may be of use:

https://www.eng-tips.com/viewthread.cfm?qid=366879