REFLECTOR: Cowl Vortex generators

[Rene Dugas]

Vortex generation got me to thinking about keeping air flow attached  
for a longer arc near the prop between the exit holes in the cowl and  
the prop. If the airflow stayed attached longer it might supply less  
disrupted air to the prop. This may be too close to the prop root to  
make difference. It might increase the drag by forming more vacuum but  
that might improve cowl evacuation.  VG's leading the NACAs helps. Two  
pairs on each top and two on the lower cowl 6 or 8 inches forward of  
the groove-might have a benefit. I've thought whether our exits should  
be rectangular to decrease air flow disruption.  Food for rumination.  
Also would VG's 6" forward of the ailerons make them more effective at  
slow speeds similar but for different reasons to fences.

Rene' Dugas
Sent from my iPhone 3G

On Mar 28, 2009, at 8:37 AM, Scott Derrick <scott at tnstaafl.net> wrote:

> As ken says, the factory has a template set for placing the VG's.  I
> believe you normally get a set of  factory  VG's with the  
> templates.  5
> years ago I convinced them to sell me the templates, sans VG's for a
> reduced price.  Maybe you can do the same..   Most of their cost was  
> in
> the placement engineering and testing so the reduction in price wasn't
> enormous, which was fine by me.
>
> Personally, I wouldn't  install them without the factory templates.
> They ran the numbers and tested that placement.  Maintaining the lift
> ratio between the canard and main wing is paramount and must be
> maintained to prevent a main wing stall.
>
> Scott
>
> KMis178813 at aol.com wrote:
>> Tom
>>   The factory has a template your looking for. The VG's that you can
>> get from them come with a template as a kit. The VG's don't cost that
>> much, knowing were to put them    priceless. Sounds like a Master  
>> card
>> commercial.
>>     Ken
>>
>> In a message dated 3/27/2009 9:24:59 P.M. Eastern Daylight Time,
>> tomcat05 at comcast.net writes:
>>
>>    Thx Scott--this was the link I forgot to add:
>>
>>    http://stolspeed.com/stolspeed-vortex-generators
>>
>>    They seem to be better than the factory ones I've seen. If I go  
>> this
>>    route is there a template available somewhere for a Velocity??   
>> Tom
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