Flow Rate vs Rev/Gal: Understanding Relationship & Calculation

[rentralgo]

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...

 

[Valerie Park]

The relationship between flow rate, rev/gal, differential pressure, and rotational speed is complex, and depends on a number of factors such as the size and type of drill string, motor, and downhole environment. Generally speaking, the rotational speed will increase with increasing flow rate and differential pressure, though the exact rate of increase can vary significantly.The flow rate is generally proportional to the differential pressure, but it can also depend on other factors such as the size and type of drill string and motor. Additionally, the flow rate can drop off at higher pressures due to increased friction and turbulence in the drill string.Unfortunately, there is no single formula that can calculate each item in this situation, as the relationship between these variables will depend on the downhole environment and equipment used. However, there are many resources available online that provide more detailed information on how these variables interact. For example, you can find a comprehensive guide to drilling hydraulics here: https://www.americanpetroleuminstit...ardsChapter13DrillingFluidsSystems_02.pdfHope this helps!