Piezometric ring sensor for air flow measurement at fan outlet


Thread Starter


I am looking for information regarding the operating principle, method for selection, calibration procedure and source for piezometric ring sensor for measurement of air flow at the outlet of a fd fan. Could anyone help please?

I'm not sure I understand your case.
There are 4 very common configurations of measuring flow, using orifice plate:
0_ vena contracta
1_ pipe taps
2_ flange taps
3_ corner taps

The last one is slightly different than the "flange tap". It uses a "piezometric ring"
or annular averaging ring (so to speak).
Stated accuracy is the same. It was very commom in Europe.
In other words, the pressure is taken within the circular ring adjacent to the face of the plate, instead of at a point at some distance from the plate like in the orifice flange.

What else can you tell us ?
I am also searching for the design specifications of the Piezometric Ring (also called a Piezometer Ring). I found application information in the ARI Standard 880-1998 and the ASHRAE Standard 130, but neither provides the design specifications of this air pressure measurement device. My application is automotive, but this device can be utilized in any air duct application. I cannot utilize a Pitot Tube because of large airflow eddies in the desired duct cross-section that I wish to measure. A Pitot Tube cannot provide repeatable air pressure measurements when the airflow is non-laminar in a selected duct cross-section. Also, a multiple Pitot Tube measurement grid is too costly and time consuming. I am looking for design information of the Piezometric Ring so that I can fabricate this device for my many specialized applications. I have used Piezometric Rings in previous positions and I am familiar with it's advantages over Pitot Tubes in non-laminar duct applications. I belive the Piezometric Ring can be easily fabricated. I need inside tube diameter, pressure tap hole sizes, ect. Can anyone help me with this?
I am sorry for mine English.
I live in Russia and I work in laboratory developing portative instruments for air flow measurement. These devices represent tubes stocked with piezometric rings.
If you interested in this, please e-mail me [email protected]

Alberto Glez

I also am looking for this information, see that you asked for it some months ago, wanted to know if you found something and if you could give some reference or information on the matter to me.

Thank you.