REFLECTOR: Molding a P-51 Scoop

[Al Gietzen]

The intercooler face is 6x22, I thought I read some formula that a 

1-to-2 expansion area in front of the intercooler was a good thing.

 

I will reread my turbo book and verify what I need.  I agree, it seems 

like a whole lot of area. I would think 1/4 of that would do.

 

Scott

 

The flow rate depends on the amount of heat to reject and the temperatures
involved - of which I have no knowledge -; but For the speeds our planes go
a diffuser area ratio of about 4:1 (or higher) gives good pressure recovery
for a 'typical' heat exchange.  So you might want to be thinking along the
lines of about 4" x 8" entrance, expanding in a sort of bell shape to the
face of the H.E..

 

It is a common misconception that a ram scoop necessarily causes more drag
than a submerged inlet (NACA), but that is not necessarily the case.  It's a
matter of the energy of the air going in, and the air going out.  With
somewhat optimal ducting (which usually is difficult to achieve), the better
efficiency of a ram scoop gives you more energy to work with in accelerating
the air again before release, and the potential for low drag.  The P-51
scoop and exit ducting is an excellent example of a very low cooling drag.

 

I'm not an aeronautical engineer, but I did stay at a Holiday Inn Express
:-)

 

Al

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.tvbf.org/mailman/private/reflector/attachments/20050905/6038a1a7/attachment.htm