Gerotor and gear oil pump formulea

[womble]

Hi,

I'm looking for any books or papers that have formulea to calculate flowrates for gear and gerotor oil pump designs. I have run a search on here but that only lead to dead ends. I've searched the SAE database too but the abstracts have not given me much detail and I don't wan't to waste my money on papers that turn out not to have what I want.
My request is due to a comparison that I want to do between two oil pump types on a engine. An early version of this engine had a gear type oil pump. The later version has a gerotor version, claimed to have a higher capacity, but I cannot extract flowrate numbers from the OEM so I want to work them out.
I hope someone can point me in the right direction.

Thanks!

 

[patprimmer]

Do you have samples of both pumps, or at least the gears or dimensions of the gears.

If you have pumps, an accurate speed controlled drive, a stop watch and a bucket will provide the answer, otherwise, if you can calculate the volume of the gap between the teeth and the body in the smallest and in the biggest volume area, the capacity is the difference times the number of teeth used per revolution of the pump.

I have measured volume of complex shapes by filling with plasticine, then placing the plasticine in a container filled with water and measuring the volume of the water displaced.

Regards

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[womble]

I have both pumps. I'll try and rig up a testing device with them. Thanks for the ideas.

Regards