Hi guys,

I have to analyse two different little silencers for water pipelines.

The aim of the analysis is to evaluate acoustic performance in noise reduction of the two silencers.

According to you is it possible and sufficient to use Star-CD Lilley's acoustic analogy?

Is there another simple method (without specific acoustic code)?

Thank you Gianni

No it's absolute not sufficient. For a silencer design knowledge about the sound spectrum is necessary. The Star approach only calulates a intensity from the turbulence for a steady state simulation. But acoustic is actually never steady state.

An easy and simple calculation method is not available due to the complexity of acoustic phenomena.

Thank you,

so the analysis with Star in not sufficient neither for a simple comparison between the two silencers.

The solution is DES analysis with Star and then Sysnoice analysis, is'nt it? But it is too expencive for this tipe of object!

Gianni

1. Yes 2. Actually sysnoise with Star is also sometimes not adequate. If you are interested in frequencies higher than 200 or maybe 250 Hz you will be also in trouble, because these frequencies can't be extracted presicely enough.

F.K.

Ok,

have you some papers or link about this type of problems?

Thank you Giovanni