Contact   Imprint   Advertising   Guidelines

Unexpected telltale results

Forum for kitesurfers
User avatar
Peter_Frank
Very Frequent Poster
Posts: 12783
Joined: Wed Oct 16, 2002 1:00 am
Brand Affiliation: None
Location: Denmark
Has thanked: 1020 times
Been thanked: 1191 times

Re: Unexpected telltale results

Postby Peter_Frank » Sun Aug 25, 2013 8:22 pm

Flaps are definitely not necessarily "slotted" :naughty:

In public transportation and for landing purposes, yes, they are (can be) slotted to sacrifice performance in order to gain easy handling and safety.

But many gliders use really efficient flaps, buried perfectly into the wing, without any "open" things to cause drag and parasite drag.

I prefer these :thumb:

8) Peter

joriws
Very Frequent Poster
Posts: 1299
Joined: Wed Nov 24, 2010 11:03 am
Gear: Flysurfer, HQ, Moses, Nobile, North, Ozone
Brand Affiliation: None
Has thanked: 76 times
Been thanked: 163 times

Re: Unexpected telltale results

Postby joriws » Sun Aug 25, 2013 9:11 pm

eree wrote:look at the nature, do any of the flying species have those slots or no central support structure (strut)?
When I look at bird wing and feathers I see controlled air passing between 3 layers of different length feathers from lower to upper surface, similar what slots do.

Image

I even found another picture naming such feather feature as a slots. Same picture compared high ar wings like albatross to high speed like hawks. Just ggl it.

If you doubt slots behaviour in general then you doubt the findings of NASA et all. There are many great videos of wings in wind tunnels with slots and flaps configuration. How maximum AoA for particular airfoil is affected, stall and lift characteristics etc.

About venturi, it probably works if it is tuned correctly. But if it allows 5 degrees more AoA before stall I think it is not easy task to test when kiting. Taping venture closed will also change speed polar of airfoil so when kiter is jumping it must be flown slightly different. Naturally the kiter is interested in final outcome, lift, but to get the optimal out is not easy task. And remember, if you are seeking lift max, flying speed slower or faster than speed at lift max will drop the lift coefficient.

User avatar
El Rudo
Frequent Poster
Posts: 301
Joined: Mon Jun 25, 2007 8:15 pm
Local Beach: Slufter NL, world
Gear: OR
Brand Affiliation: Ocean Rodeo
Location: NL
Has thanked: 0
Been thanked: 0
Contact:

Re: Unexpected telltale results

Postby El Rudo » Sun Aug 25, 2013 9:43 pm

MikeYQM wrote:I dont have a OR kite.
OK I got that wrong. Well at least you've got some wind tomorrow, enjoy!
cheers, Rudo

User avatar
Bille
Very Frequent Poster
Posts: 4026
Joined: Sun Sep 04, 2011 5:37 pm
Local Beach: Lake Mohave
Gear: Ozone Edge
Brand Affiliation: Barz Optics
Jaybar Dynabar V7
Has thanked: 252 times
Been thanked: 189 times

Re: Unexpected telltale results

Postby Bille » Sun Aug 25, 2013 11:33 pm

Peter_Frank wrote:Flaps are definitely not necessarily "slotted" :naughty:

In public transportation and for landing purposes, yes, they are (can be) slotted to sacrifice performance in order to gain easy handling and safety.

But many gliders use really efficient flaps, buried perfectly into the wing, without any "open" things to cause drag and parasite drag.

I prefer these :thumb:

8) Peter
Your absolutely correct on this Peter ; i was saying that it would be Unwise
to rule Out the possibility that this technology "Can" be instigated into our kites.
I'm saying the concept needs More work.

When Ya think about it , we haven't even used a Flap on our kites , (slotted or otherwise);
and I Know for a FACT they work, cause i have them on my HG !!

& YES , i also can fly the sailplanes that have flaps integrated into there systems, and
they work quite well , (with And without the slotted feature). -------------blanik sailplane...

Honest ----- i'm NOT trying to be Rude, especially to a Guy with your expertise. I would
be Sad if you thought otherwise !!!

Bille

User avatar
Kamikuza
Very Frequent Poster
Posts: 7057
Joined: Fri Jan 09, 2009 4:49 am
Local Beach: Sabae Beach
Favorite Beaches: Ol' Stinky
Gear: This, that, the other
Has thanked: 220 times
Been thanked: 193 times

Re: Unexpected telltale results

Postby Kamikuza » Mon Aug 26, 2013 1:19 am

Peter_Frank wrote:Flaps are definitely not necessarily "slotted" :naughty:

In public transportation and for landing purposes, yes, they are (can be) slotted to sacrifice performance in order to gain easy handling and safety.

But many gliders use really efficient flaps, buried perfectly into the wing, without any "open" things to cause drag and parasite drag.

I prefer these :thumb:

8) Peter
Extremely high AR those wings, aren't they?


Return to “Kitesurfing”

Who is online

Users browsing this forum: Bing [Bot], Breze, buzzz, Da Yoda, evan, Google [Bot], sflinux, Yahoo [Bot] and 563 guests