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Date: Sun, 15 Nov 2009 14:12:52 -0500
From: Ernest Christley <echristley@nc.rr.com>
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To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: Phononic bandgap muffler
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Al Gietzen wrote:
> Ernest;
>
> Interesting stuff.  Just a guess; but it seems to me that, while 15 db is an
> appreciable reduction, having that reduction only over the 8K to 12K maybe
> isn't all that productive.  It would reduce the 'harshness', but isn't the
> greatest amplitude at lower frequency?  Also, do you envision that this can
> be made into a compact, workable package for aircraft application?
>
>   
Don't know, Al.  That's why I've started my experiments with a wood box 
and pieces of PVC tube.  I don't want to send much money down a rabbit 
hole if I can help it.

That said, my experiment box is 3" high, 7" wide and 6" long.  I'm going 
to see what I can do about getting some stainless sheet cut up, and then 
some tube welded in.  Then I'll have to find a rotary that I can test it 
on.  Shouldn't be difficult with Bruce Turrentine being 15min down the road.

-- 
Ernest Christley, President
Ernest@TechnicalTakedown.com

TechnicalTakedown, LLC
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