Calculating Compressed air leaks within a system

[rl424]

Hi all, new to the forum, but I was wondering if anyone could help me as I'm going round in circles. After completeing an air leak survey and noting the hole diameter, dB reading of the leak and knowing the pressure of the system (bar) how can I calculate the leak rate CFM and the Energy wasted (kW). Or is there some kind of standard/approximate table I can use.

Thanks in advance

 

[JaredJames]

I've done something similar in the past for testing various units.

You seal input / output of the unit and increase the internal pressure to a set value. You then take internal pressure readings over a set period (we used each minute for 15 minutes).

After which time you know the pressure drop over a set time which you can convert to leakage rate per unit time.

I'll try to dig out the equation for you (it's fairly simple), but if you could describe your setup it would help me determine if it's right for you.

 

[Charlied]

Hi all, new to the forum, but I was wondering if anyone could help me as I'm going round in circles. After completeing an air leak survey and noting the hole diameter, dB reading of the leak and knowing the pressure of the system (bar) how can I calculate the leak rate CFM and the Energy wasted (kW). Or is there some kind of standard/approximate table I can use.

Thanks in advance

I've done this for my work also. I used a chart like this one for the flow calculation for an example of a 1/8th inch hole leak at 24-7. http://www.trident.on.ca/orifice-air-flow.htm
Divide the flow into the compressors capacity and find the percent of it's capacity. Multiply the compressor loaded kw by the calculated percent of the leak. That times the utility kwh rate is part of your cost. The other cost is the maintenance of the compressor for the percent of the leaks. The cost of air leaks in a large plant is mind-blowing.

 

[GT1]

You can try using the formulas at this link:
http://www.air-dispersion.com/feature2.html