I want to pump fluids (flow rate) through a drill string to a downhole motor some distance beneath the surface building up some differential pressure (psi). depending on the amount of differential pressure and the flow rate (gpm) the motor rotates at some rotational speed (rpm). what is the relationship between flow rate (gpm), rev/gal, differentail pressure (psi) and rotational speed (rpm)? Is the speed constant or rev/gal constant or linear? Is the flow rate linear as the differentail pressure increases or a drop curve? If a drop curve, what might be the variables that cause this drop? Is there a good sight that explains this in a simplistic manner? Is there a formula to calculate each item? any help is appreciated....(adsbygoogle = window.adsbygoogle || []).push({});

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# Flow rate vs rev/gal

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