Calculating sound level from air flow through a stack? possible?

[SylvestreW]

I'm faced with an interesting problem. I frequently need to determine the sound power levels coming from industrial exhaust stacks. Problem is, a lot are inaccessible (we're talking >30m above grade).

In most cases, I know the flow rate (cfm), the diameter, if the flow is laminar or cyclonic etc, the stack material, the gas temperature, humidity, composition etc, as well as the ambient conditions etc.

Is there a formula that would allow me to plug variables in to calculate (within a few dB) the power levels?

Thanks.

 

[khan101]

Noise tests can be performed to ISA S75.07 or the essentially equivalent international standard, IEC-534-8-1. Hydrodynamic noise can be measured using IEC-534-8-2. It is often impractical to test at actual service condition. Methods for predicting the noise at actual service condition must be used in those cases. I hope this helps.