Reducing acoustic energy loss from bellmouth open pipe

[edjza80]

Heya folks, i have done a chunk of research (not my field!), and am having trouble relating the infomation im reading back to my specific query... which is:

regarding... the delicate balance between reducing the pumping losses by applying a bellmouth to a duct termination, and at the same time, suffering the increased loss of radiated acoustic energy from within the pipe at this same bellmouth interface.

obviously the acoustic boundary for a standing wave is not as strong in a pipe with a bellmouth. How can i make this acoustic boundary better, without totally screwing up the flow character of the bellmouth?

ideas, or reading specifically focused at this problem would be appreciated.

cheers
ed

 

[BigInch]

Restricting the flow unfortunately goes hand in hand with restricting the accoustics. Each is the cause and the direct result of the other, much as is the chicken and the egg.

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO, BP

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