REFLECTOR: Intercooler pictures

[Joe Ewen]

FYI
If anyone is looking for information on inlet / diffuser design.there is a 
book "The Aerodynamics of Propulsion" by Kuchemann and Weber, (the 
publication is often referred to as "K&W") that is a very good source.  On 
the FlyRotary list (Rotary Motors in Aircraft) this seems almost to be the 
bible of cooling diffusers.  They endorse a streamline diffuser, which is 
best described as trumpet shaped, with the coordinates of the trumpet well 
defined by formula.  The advantages of this diffuser style is a shorter 
length, better pressure recovery and more even pressure distribution.  I am 
using the K&W streamline diffuser design for both water and oil cooling, but 
am not flying yet so my installation is yet to be proven.  Al Gietzen does 
have a SE / Rotary that is flying, which I believe is based on the K&W 
information.

For What Its Worth,
Joe




----- Original Message ----- 
From: "Brian Michalk" <michalk at awpi.com>
To: "Velocity Aircraft Owners and Builders list" <reflector at tvbf.org>
Sent: Thursday, August 30, 2007 9:13 PM
Subject: Re: REFLECTOR: Intercooler pictures


> The fairing is not installed on the pics I sent.
> From the side view, go to a position about six inches fore of the
> firewall, and about 1.5 inches below the fuselage.  Now, from that
> point, make a straight line to the edge of the intercooler, and continue
> it to the IC exhaust.  That's about where the fairing will be.  Of
> course any hard angles will be smoothed out.
>
> The intakes and exhaust caps on the intercooler need to be tapered.  If
> they are not tapered, then the IC has most of the air going through one
> end.  The fairing I described provides that taper.  I am also relying on
> a good deal of vacuum at the exhaust end.
>
> After saying all that, I'm going to fly with and without the "scoop" to
> the intercooler.  I have a hunch that I'll be just fine without the scoop.
>
> gpoole wrote:
>> Thanks for sharing the pix of your cooling arrangement Brian... if you'll
>> pardon me for  posing some dumb observer questions....cause I just don't 
>> get
>> it!
>>
>> For a moment I thought you had scoops pointing forward...but now I 
>> realise
>> they are more likely outlets facing aft (as outlets obviously should!) - 
>> but
>> if that is the case just how does air go thru your radiator?  I thought
>> smooth transitions in change of direction were the order of the day and 
>> that
>> from a small scoop opening, one made a large area to slow the air down 
>> and
>> build pressure, so for your design how does relative airflow do a 900 to 
>> go
>> up and then 900 again to exit? I have always considered the  P51 
>> arrangement
>> as a proven design and it canted that aircrafts' radiator to align it 
>> with
>> the flow of air down its' duct.
>>
>> Your cooling radiator looks way bigger than any I've examined and I would
>> have thought it's positioning would necessitate a much larger and
>> subsequently a much draggier scoop to accommodate it and the space air 
>> will
>> need to flow?
>>
>> Best as always...
>>
>> Greg
>>
>>
>>
>>
>> -----Original Message-----
>> From: reflector-bounces at tvbf.org [mailto:reflector-bounces at tvbf.org] On
>> Behalf Of Brian Michalk
>> Sent: Friday, 31 August 2007 7:07 AM
>> To: Velocity Aircraft Owners and Builders list
>> Subject: Re: REFLECTOR: Intercooler pictures
>>
>> Yes, they are too big for the horsepower.  Also referencing Corky Bell.
>> However, if I recall correctly, these were the smallest I could find for
>> motorcycle ... I seem to recall RGM racing, or RJM racing.  I would have
>> done better to go with a single intercooler, but it was a much simpler
>> install to go with the split IC.
>>
>> Scott Derrick wrote:
>>> Brain,
>>>
>>> Interesting design.  So the cooling air makes an "S" turn as it goes
>>> through the intercooler?
>>>
>>> How did you calculate the intercooler size?  My intercooler doesn't look
>>> anywhere
>>> near that big, I used Bell's formula from his book "Maximmum Boost".
>>> His company made my intercooler and I had one of their engineers verify
>>> my size requirements for 325 HP.   The intercooler that came with my
>>> engine was about %15  larger than the new I had built but the cooling
>>> air through that one also had to make an "S" turn like yours to get
>>> through.  Both were made by Bell.
>>>
>>> Hopefully I haven't undersized it.  I have a temp probe right after the
>>> intercooler to monitor the boosted air temperature.
>>>
>>> Scott
>>>
>>>
>>>
>>>
>>>
>>> ------------------------------------------------------------------------
>>>
>>> _______________________________________________
>>> To change your email address, visit 
>>> http://www.tvbf.org/mailman/listinfo/reflector
>>>
>>> Visit the gallery!  www.tvbf.org/gallery
>>> user:pw = tvbf:jamaicangoose
>>> Check new archives: www.tvbf.org/pipermail
>>> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html
>


--------------------------------------------------------------------------------


> _______________________________________________
> To change your email address, visit 
> http://www.tvbf.org/mailman/listinfo/reflector
>
> Visit the gallery!  www.tvbf.org/gallery
> user:pw = tvbf:jamaicangoose
> Check new archives: www.tvbf.org/pipermail
> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html