Frictional pressure loss of a pipeline pig
Frictional pressure loss of a pipeline pig
(OP)
I need to calculate the time taken for a pig to accelerate from an initial to a final velocity in a pipeline. (The reason this value is of importance is because it determines the level trip settings of an upstream vessel.) I know how to calculate this value using the mass and size of the pig and the pressure driving force available, but how do I include the frictioal loss component?





RE: Frictional pressure loss of a pipeline pig
Frictional loss equals a scalar coefficient times normal load, a negative vector relative to flow. This scalar coefficient is initally static friction factor until just after initiation of motion, then the kinetic friction factor can be used.
I would treat it no different than a block sliding down an incline plane under the influence of friction. This would give you a beginning point to model your equations for a mathematically equivalent pipeline system. After that, you can tinker with the differential equation(s) to your hearts content in order to gain accuracy.
Sounds like a nice problem, enjoy the moment!
Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada