Al; when you reply to Georgie, send plain text to remove rich text/html effect. jofarr

----- Original Message ----- From: Al Gietzen
To: Rotary motors in aircraft
Sent: Monday, June 27, 2005 4:14 PM
Subject: [FlyRotary] Re: NPG + use in aircraft??



George B.;

Nucleate boiling (small steam bubbles forming and dissipating) provides the highest heat transfer coefficient from the surface to the coolant; better than no boiling.  Film boiling, on the other hand, is when there is a layer of steam between surface and coolant, and the heat transfer coefficient drops precipitously.  The occurrence of film boiling is a very bad thing, causes serious hot spots in the walls, and can damage the engine.

Al G.

P.S.  Can we dis the background on these messages?

-----Original Message-----
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]
On Behalf Of Echo Lake Fishing Resort (Georges Boucher)
Sent: Monday, June 27, 2005 11:51 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: NPG + use in aircraft??

Rusty
"boiling removes heat" I have a hard time understanding that quote. When racers started using PG they were able to run 15:1 compression on "pump" fuel
due to the fact that boiling coolant created hot spots in the combustion chambers & in turn causes pre-ignition (they also reversed the coolant flow direction to bring the cooled coolant to the hottest part of the system, & all this with no pressure cap. The one disadvantage I see in the 13b is that it can't handle the potential higher boiling point of PG. I have a 3.0 L V6 that I reversed the cooling system on to use in the Christavia (that was before I got hooked on the 13B)
Georges B.