Static pressure measurement and best methodology
Static pressure measurement and best methodology
(OP)
I have few questions with regard to static pressure measurements:
I am trying to understand which is the best place to place a static pressure probe and how it is affected by eddies/turbulence , valves, pipe bends etc....links to papers / detailed explanations would be very helpful
Is it common to see static pressure bouncing around if is placed in eddies/regions of flow swirling ?
Are there good practices to measure accurate static pressure in pipe flow/ near valves ?
Looking forward to your answers....
Thanks,





RE: Static pressure measurement and best methodology
RE: Static pressure measurement and best methodology
Best place for highest accuracy is in a long pipece of pipe with no flow distrurbances (elbows, valves, tees etc) within 5D min of the pressure tapping.
There are many things and codes written about where the tapping needs to be for orifice meters to get the required accuracy.
Does the term "probe" imply something entering the fluid? like a pitot tube?
If yuo put your PI immeadiately downstream of a control valve which is throttling and creating a lot of noise, turbulence and vapour bubbles the it will bounce around a bit, ditto d/s of a PD pump which doesn't have a multiple cylinders and a damper.
Otherwise valves should be open or closed so really no different to pipe, unless they leave something in the flow like a butterfly valve or swing check valve.
A lot depends on the accuracy you're trying to obtain and the purpose behind the reading, but in general try for simple straight bits of pipe.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Static pressure measurement and best methodology
If so, then eddies or turbulence are meaningless and location would be directly related to elevation.
Or am I missing something?
RE: Static pressure measurement and best methodology
However if the fluid itself is subject to pressure changes and fluctuations then the reading on the guage is not representative of the pressure in the fluid and I think that's what the OP is actually asking.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Static pressure measurement and best methodology
Good luck,
Latexman
To a ChE, the glass is always full - 1/2 air and 1/2 water.
RE: Static pressure measurement and best methodology
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Static pressure measurement and best methodology
Regarding: I am trying to understand which is the best place to place a static pressure probe and how it is affected by eddies/turbulence , valves, pipe bends etc....links to papers / detailed explanations would be very helpful
Is it common to see static pressure bouncing around if is placed in eddies/regions of flow swirling ?
You are observing the total pressure of the combined static pressure and dynamic pressure.
If a fluid is not moving (and open to atmospere), the measured pressure is the same in all directions is the static pressure. But if the fluid is moving, the measured pressure depends both on the static pressure and on the pressure caused by the energy of its motion, in the direction of that motion. The added pressure from the fluid's motion is called dynamic pressure.
If you want to measure the static pressure accurately, the fluid will have to be at rest.