<VV> Air vs Water HP

[JVHRoberts at aol.com]

Well.....
 
A Corvair fan, no doubt, uses more HP than a water pump, there can be no  
doubt. Given that electric cooling fans can cool waterpumpers just fine, with  
reasonable amounts of power, but NOT a Corvair engine, it's pretty clear that  
the Corvair has the more HP intensive cooling solution. But then again, even  
911s use more power for cooling than water pumpers. 
Water has SO much more specific heat and density than air, even modest  
amounts of pump HP can move heat away from an engine easily. 
Radiators have extended fin areas, with MANY times more square feet of  
cooling surface than ANY air cooled engine of the same power, that the air flows  
easily through it, with little pressure drop. Corvair engines need LOTS of  
pressure drop to get good heat transfer, and even then, it's not that good. 
 
That being said, Corvair cooling fans don't consume huge amounts of power  at 
cruise. But at full power, that's another story, by a BUNCH!! 
 
John
 
In a message dated 7/8/2005 4:09:42 PM Eastern Standard Time,  
minoxphotographer at yahoo.com writes:

Just a  curious question.
I have read a few articles about how the Corvair cooling  fan uses a
chunk of horsepower to do it's job.  How does it compare to  the
waterpump/fan horsepower used in a conventional engine?  Which  turns
out to be more effecient?  Just wondering.

Tim in  Bovey