|
Ok, Jim
Got your point. I agree,
my experience indicates that attention to details in and around the inlet/plenum
pays high benefits. I suspect that if I reduced the second inlet by the
same amount that cooling might be compromised - but, don't know as haven't tried
it. I believe that my second unmodified duct is picking up some of the
load. However, its clear that regardless of what area I end up with when
all is said and done, it will be smaller with less cooling drag than if I had
not smoothed the ramp.
I also agree that 7 Deg has
aways struck me as pretty low. Actually when I plotted the curves to help
me contour the shape of the foam, there was no way 7 deg would work with the
length of my duct. So I decided that I would plot a curve that diverged no
more than 7 deg/inch - which would give me a approx 21 Deg divergence over the 3
or so inches from inlet to radiator. I must be getting some flow
separation, however, it appears that (as you would imagine) that it is not as
bad with my previous (sharply divergent) inlet.
So, nice to realize we are in "violent agreement"
{:>)
----- Original Message -----
Sent: Monday, October 06, 2003 12:12
AM
Subject: [FlyRotary] Re: Thick Vs Thin
Radiators - NASCAR
Ed,
<... Did this help or did I just make it more
confusing ...>
Once again we find ourselves in "violent agreement" ...
:o)
In your crude "box" plenum, (or any design with too sharp corners)
when the air couldn't negotiate the turn, it separated, became a turbulent
eddy and stopped going anywhere or doing anything useful. Smoothing out
your ramps reduced inlet from 24 square inches
to 8-9. That's 2/3!! A HUGE savings in cooling
drag. That is what I was trying to get across. Merely delivering
air to the radiator face is not enough. We have to deliver it in a
sufficiently organized manner to enable it to work as efficiently as it
can. I know 7 deg is hard to achieve in our limited space, but my
objective is to have everyone giving it their very best shot at 7 deg, and
accepting what they end up with as the best package they can make, rather than
just hanging radiators out in the sky.
I was surprised that it was only 7 deg. I expected more like 20 ....
Jim S.
|