REFLECTOR: The use of VG to aid cooling

[Darrell & Nora Kufalk via Reflector]

Ron,

A few years back, I tested the 1/4" tall VGs in front of my NACAs.  I was very careful to position them just as described in the old Velocity Views newsletter.  I used RTV to install them the day before the test.  I flew 25 miles, got some gas, removed them and flew 25 miles home.  Same OAT.  Same power settings.  Same climb rate.  Same altitude.  Same cruse speed.  I downloaded my engine data and carefully studied it.
I got exactly ZERO degrees lower CHTs between the 2 flights.

Darrell
XL-RG IO-540


-----Original Message-----
From: Reflector [mailto:reflector-bounces at tvbf.org] On Behalf Of Ron N VelocityXLFG via Reflector
Sent: Tuesday, September 30, 2014 11:56 AM
To: Velocity Aircraft Owners and Builders list
Subject: Re: REFLECTOR: The use of VG to aid cooling

Great Job ! . But now I ask the question how is it so many builders claim the small vg's help when your info so clearly says it does not. I have small vg's  in front of my nacas
and was sure they helped till now. :(   I have now put testing my naca 
intake back on the testing list. Oh well more fun things to experiment with :-) .

Great article so loaded with great info.


Ron



On 9/30/2014 8:48 AM, Matt Bucko via Reflector wrote:
> Well done David.
> Matt
>
>
> On 9/29/2014 5:09 PM, David Ullman via Reflector wrote:
>> My Velocity has always run hot.  I have fixed this with the use of 
>> Vortex Generators aiding the flow of air into the NACA ducts on top 
>> of the fuselage.  For a full report go to:
>>
>> https://davidullman.com/uploads/THE_USE_OF_VORTEX_GENERATORS_TO_ENHAN
>> CE_PUSHER_AIRCRAFT_COOLING.pdf
>>
>>
>> Comments appreciated.
>>
>> To see recent photos of N444DX hangared in Independence Oregon, go to:
>>
>> https://davidullman.com/VelocityPhotos.php
>>
>> David Ullman
>> David at davidullman.com
>>
>>
>>
>> _______________________________________________
>> 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

_______________________________________________
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