Mailing List lml@lancaironline.net Message #3208
From: John Spry <spry@pop.ihug.co.nz>
Subject: Ram Air intake
Date: Sun, 22 Aug 1999 16:46:35 +1200
To: <lancair.list@olsusa.com>
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Has anybody any experience in modifying the air intake and cowling to
increase the manifold pressure ?

In particular would it be worthwhile to enlarge and extend forward the air
intake in the cowling to take advantage of the airflow created by the prop ?

I look forward to comments

John Spry

 
[I think all the thrashing of the air nearer the prop is actually counter
to what you're trying to accomplish... P1*V1=P2*V2... or low pressure times
high velocity equals high pressure times low velocity.  So the trick here
is to get the ambient pressure air coming into the duct's entrance as
fast as possible so you can slow it down inside the duct to jack up the
internal pressure.  Then you have all the losses through the induction system,
so you're lucky to have the intake air pres even back up to ambient.  I
think if you want to boost (hint, hint) the MAP, the only way you can
do it is with a pump, like a turbo or supercharger.  There is no free
lunch and all laws of physics will be strictly adhered to.

My $0.02 only, and I freely admit that I might be all wet here by thinking
out loud, so all you engine optimization types please jump in and
straighten us both out with the straight poop.

   <Marv>     ]



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