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Date: Wed, 14 Nov 2007 10:33:28 -0500
From: Ernest Christley <echristley@nc.rr.com>
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To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: Rebutal to the rebutal {:>) Thick vs Thin was
 : Diffuser Configuration Comparison
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Ed Anderson wrote:
>  Q = m cp DeltaT.  Clearly shows that heat removal is proportional to BOTH mass flow AND deltaT (as well as the specific heat but that is fixed by nature).   Yet, for some reason that I still don't understand, you skeptics seem to fixate on the mass flow factor {:>) and ignore DeltaT as if it were a factor you can do nothing about.  
>   
I think that is because you're reducing mass flow for the thick rad.  
You could do the same for the thin rad, and end with the same deltaT.  
To fairly compare the radiators, you have to fix the airflow at the 
inlet and decide which option you can get to dump the most heat into the 
air while offering the least drag.

Of course, out here in the real world it doesn't work that way.  
Everything affects everything else, and we have to design the whole 
system.  We rely on generalities and ROTs, and hope that we wind up with 
something that has a passing aquaintence with "optimized".  Most of us 
will settle for a not to distant relative of "it works".