Dave Garber was about 35 years ahead of his time.
     This rad had oblique tubes. Dave told me it cost about $1000
each. They were intended to cool 350 HP each.

     I think it would be easier to make if the fins were in there 45
degrees instead of the tubes. That possibly would reduces our
drag in our flat installations. We need to get a quote from some
of the rad makers.

     BTW Dave said it did not cool. He was using NACA scoops.

NACA scoops or not, if his installation did not cool, why risk $1k per
radiator on something that has proven it did not work? Are there any
working examples where oblique cores were proven to work where
straight cores were shown in the same installation to not work?
...Chrissi

www.CozyGirrrl.com
Cozy Mk-IV RG 13B-turbo
Plans #957 Chapter? big pieces done, details, details

It is just common sense that they should work better and created less
drag. The air must make only a 45 degree turn rather than a 90 degree
turn to go through the core. I think it is worth a try after we get the
more wide spread serious problems solved.

Paul Lamar

Matt Prather wrote:

Isn't the idea to slow the air so that changing it's direction is
no-biggie?  Also, doesn't
making the fins angled just make the core look thicker?

Matt-

Yes but actual measurements on a 90 degree system show that the air velocity
through a rad can be up to 50 percent of the forward velocity. This is why
it is important to keep the back side of the rad unobstructed. This is particularly
important with modern high efficiency thin heat exchangers.
The ideal heat exchanger is of infinite frontal area with infinitesimal thickness.
The Dodge PU Truck rad is almost good example :)
First half of the rad does 3/4 of the heat transfer. Rule of thumb.

Having said that the strange thing about cooling systems are the number
of interdependent  factors that tend to off set each other making the design
a very complicated process. Improve one factor and some other factor gets worse.
In other words it is very very difficult to sort out real improvements. 
Kays & London published a 20 year multi million study on heat exchanger 
simply called Compact heat Exchangers. I highly recommend it.
 
Paul Lamar
 
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