dP Calculations trhough Valves with Multi-Phase Fluids 2

[SuperG]

Hey folks! How do I calculate the pressure drop across a valve using a multi-phase fluid?

I am calculating pressure drops through ball valves and check valves, now I need to do the same for 3-way valves. I am at a loss regarding pressure drop for the 3-way valve. Also, after some deliberation, I wonder if the pressure drop across valves using liquid or gas is drastically different than a multi-phase fluid, such as oil/water/gas? Any ideas?

 

[KernOily]

Hey folks! How do I calculate the pressure drop across a valve using a multi-phase fluid?

Use PipePhase with your favorite multiphase dP correlation, e.g. BBM. Use the built-in k-factors in the device screens for the valve in question.

I am calculating pressure drops through ball valves and check valves, now I need to do the same for 3-way valves. I am at a loss regarding pressure drop for the 3-way valve.

You should be able to get the k-factor or the Cv for that valve from the valve manufacturer. Call him up or look in the valve catalog. Stick that k-factor or Cv into PipePhase on the valve device screen, push the blue arrow, and go to town. I think there's also a Cv for a 3-way in the Cameron book. Is your 3-way valve a Kimray?

Also, after some deliberation, I wonder if the pressure drop across valves using liquid or gas is drastically different than a multi-phase fluid, such as oil/water/gas? Any ideas?

Shoot yes it's different. Don't EVEN use the single-phase dP correlations (e.g. Darcy) for a multiphase fluid. How much different is different? Order of magnitude is 50% and I can defend that from field measurements vs. calculations. Another thing - don't EVEN do two-phase dP calcs by hand. It will take you hours. Don't ask me how I know. Why fart around with it if you don't have to? You said you had PipePhase, now make that bad boy pay for itself! ;-)



Thanks!
Pete
P. J. (Pete) Chandler, PE
Principal Engineer
Mechanical, Piping, Thermal, Hydraulics
Processes Unlimited International, Inc.
Bakersfield, California USA
pjchandl@prou.com

 

[SuperG]

Thanks again Pete!

 

[KernOily]

No problem dude, just write back if you have any more questions. - Pete Thanks!
Pete
P. J. (Pete) Chandler, PE
Principal Engineer
Mechanical, Piping, Thermal, Hydraulics
Processes Unlimited International, Inc.
Bakersfield, California USA
pjchandl@prou.com

 

[unknown]

Dear all,
I am preparing a brief presentation on piping component. Any good reference/ ready made materials out there for me to grab/hold on that I can use. Kindly seek assistance.
TQ