Gerotor volume, RPM and displacement calculations

[msakaria]

Hello all,

I am working with a gerotor that I have no information about. I have the gerotor sample with me. Can someone please explain to me how I can measure the volume of the fluid the gerotor dispenses? Plus how can I measure the RPM and Torque of the gerotor?


Thanks,
Mo

 

[hydtools]

Parker Gerotor site should give you the element displacement bases on number of lines and length of the element.

Ted

 

[hydtools]

See this document.

Ted

 

[msakaria]

The gerotor that I have is a custom gerotor.

If I have the physical part (inner and outer gears. I was hoping to use the part to measure the volume.


Ted, the link you sent is not working.

 

[hydtools]

Gerotor Selection & Pump Design v1.3.pdf

Google for this document.

I'm having difficulty uploading a file.

Ted

 

[msakaria]

Ted, thank you for replying. I looked over the document and I am not sure how this can help. It seems like this document would help if i had the displacement of the gerotor which is exactly what I am trying to determine. This is for Nichols Portland gerotors and I have a custom gerotor. I have no way of knowing what the displacement for my gerotor is.

Mo

 

[MintJulep]

Positive displacement device.

https://www.youtube.com/watch?v=1J3a3b54rqE

 

[hydtools]

Do the physical characteristics match any of the Nichols elements? Tooth count of the inner rotor? The OD of the outer ring?

I have used "standard elements" in a customized design by specifying the custom length of the elements.

Ted

 

[gruntguru]

Had to think about this for a while.
If the inner and outer rotors of your gerotor fit neatly (ie minimum volume = approx zero), you can approximate the displacement by filling the pumping space with a measured volume of liquid. During operation, half of this volume is expanding and the other half is reducing. The half that is reducing will be all discharged in a half revolution of the inner rotor so the measured volume is roughly the displacement of the gerotor per rev.

If the minimum volume is greater than zero, the displacement will be reduced by this amount. You may be able to roughly measure the minimum volume by sealing the rotors with a film of grease and filling the minimum volume with a measured volume of liquid. Multiply this by the number of teeth on the inner rotor and subtract from the total volume measured previously.

je suis charlie

 

[3DDave]

hydtools - the file posting system doesn't tolerate unusual characters in the name, like ampersand. It's odd that it let's the file get posted, but the & prevents the file from being downloaded. It's also not keen on spaces in file names.

 

[hydtools]

Thank you 3DDave.

Ted

 

[hydtools]

http://www.ehow.com/how_7725066_do-calculate-displacement-gerotor.html

msakaria, try this. Archimedes to the rescue.

Ted

 

[msakaria]

Thank you all for the help!