Noise Generation in Piping

[df72]

I'm trying to find information on calculating the possible dB of a 10in-6in reducer in a piping system. So far I have not been able to find any data on this type of calculation. I was thinking it would be part specific, so does the manufacturer have that data? Any help is appreciated.

 

[pipingdesigner]

I'm not trying to be funny here, but wouldn't that have more to do with the velocity, viscosity and state of whatever the pipe is carrying?

Not really something that I've ever had cause to consider!

pipingdesigner

http://www.pipingdesigners.com

 

[JLSeagull]

Checkout ISA 75.17 regarding control valve aerodynamic noise prediction calculations. I would not worry much about a reducer.

The following is lifted from section 2 Limitations:
"In the typical control valve, little noise travels through the wall of the control valve. The noise of
interest is that which travels downstream of the valve inside the pipe and then escapes through
the wall of the pipe to be measured typically at 1 meter (3 feet) downstream of the valve body and
1 meter (3 feet) away from the outside surface of the pipe.
The majority of the test data available to validate the method is from air at moderate downstream
pressures and temperatures; however, it is believed that the method is generally applicable for
other gases and vapors and at higher pressures. The equations include terms that account for
fluid density and ratios of specific heat."

 

[df72]

First of all thank you for the responce's. I understand that it is fluid property related. I was trying to find any equation's or data for determining db. I will try and find a copy of the ISA code, it looks like it could help. Thank you.