Anderson Ed wrote:

Paul, I tried working through the example on radiator sizing and unless
I am mistaken there appears to be several error.

For example  in the second part of the equation solving for G*d/u*gsubo
they get 4.58(10)^3 or 4580.  Yet in the next equation solving for h
they insert (458000) or 4.58(10)^5 (don't understand where they get the
increase) and get an h of 19*(10)^-4 (at least it looks like a 4 hard to
read). But, I get 4.77 (10)^-3 using the 4.58*(10)^3 figure.  Even using
their numbers I get 19*(10)^-1 vice their 19*(10)^-4 (if that is a 4
guess it could be a 1).  19*(10)^-1 is the value for h they use in the
next equation solving for Delta T so looks like even they did not use
the value they calculated previously or I simply am not reading the
exponent value correctly.

In their calculation for 1 Ft2 of flow area they use 4(12)/(0.25)(units
in inches) and get 192 ft^2 and I get 192in^2.  They do throw in a
number of conversion factors converting minutes - seconds and
inches-feet so perhaps the answer is correct, but I can't get there even
using their numbers.

Perhaps someone who understands this much better than I do can tell
whether I am screwing up or there are errors. Looks like it would be a
useful set of equations.

Ed Anderson

I think you are going to need to get the book Ed and 
start at the beginning of chapter eight. There is so much leading up
to that example. After I uploaded it I had second thoughts about
doing so. Taylor is so intenses you can spend a week on one paragraph.

The Internal Combustion Engine in Theory and Practice. 

Volume 1: Thermodynamics, Fluid Flow, Performance. Second Edition 
Revised. 

Volume 2: Combustion, Fuels, Materials, Design. Revised. Charles 
Fayette Taylor. The MIT Press Cambridge Massachusetts, and London 
England.  

You are real lucky to have the Library of Congress at your
disposal. I did a lot of vehicle dynamics studies there when I was
attending GW as a physics major. They may also have the NACA papers
mentioned in the Taylor references on radiators that you can photo copy.
 
PL

 
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