Hello Everyone,(adsbygoogle = window.adsbygoogle || []).push({});

I'm new hear & am hoping that someone can help me out.

I have two Rotors, one on each end of a shaft with bearings in the centre, both have air cooling fins in the centre of each rotor.

I need to calculate the Inertia of these Rotors, I have looked at several formula's but there seems to be difficulty calculating the inertia due to the cooling fins etc.

I thought I may be able to drive the Rotors on the shaft to a given speed then disconnect the drive & use the time it takes for the rotors to come to a stand still to calculate this.

I will just use a very light oil on the roller bearings for the excersise & also blank off the cooling fins so they have don't have drag etc.

Neglecting Bearing friction, will this method give me fairly accurate results?

I have not been able to find the formula's for this & was hoping that someone may be able to help me out.

An example would be very helpful.

I can weigh the rotors & the shaft to get the mass if this is required.

Thank You

Henry C

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# Calculating Inertia Of Rotors

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