Talk:Dissymmetry of lift

Thanks to whoever added the links

Proposed merge

Copied over from Wikipedia talk:WikiProject Physics

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Dissymetry of Lift looks more complete than Dissymmetry of lift, but the correct title is "Dissymmetry of lift". Maybe someone can cut the Dissymetry of Lift and paste it over Dissymmetry of lift. Would that be sufficient for a merge? GeorgeJBendo 07:51, 11 November 2006 (UTC)

In doing this one should make sure no useful information is lost. Calling the article Dissymetry of Lift "S" for "source" and Dissymmetry of lift "T" for "target", the most appropriate procedure for this particular case (S is "better", T has the proper title) would appear to be:

1. Open S and T in two separate edit windows.
2. Cut/paste any non-redundant useful content from T into S.
3. Cut/paste the entire content from S into T.
4. Preview and edit T until it looks good and consistent, and then save it, with an edit summary "merge content from [[Dissymetry of Lift]]"
5. Replace the contents of S by #REDIRECT [[Dissymmetry of lift]] {{R from misspelling}} to the source page, and save it.
6. Check "What links here" on S for "double redirects" (pages redirecting to the now redirect page S).
7. Fix any double redirects by making them redirect directly to T.

 --Lambiam^Talk 09:00, 11 November 2006 (UTC)

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Done. --Guinnog 21:12, 6 December 2006 (UTC)

Analysis

1. Dissymmetry of lift exists or occurs across any kind of rotor in translating flight.
2. This article sounds more like a proof than an encyclopedia article discussing an aerodynamic condition of rotorcraft flight.
3. Anyone reading this article will be most likely end up more confused due to the amount of errors in the article.

I was gonna redirect part of another article to this one, but I am considering just filling out the section of the other article instead. I won't edit this article, I would prefer to start over from scratch. --Born2flie 05:01, 20 February 2007 (UTC)

Agreed; the "analysis" graded as an epic fail for its (in)ability to communicate its subject to the general reader. I've re-written it, just about completely. My version probably isn't perfect, but I hope it communicates better. Feline Hymnic (talk) 15:51, 27 December 2011 (UTC)

hm

I work in the rotorcraft industry and have a rotor aeromechanics background. While dynamic stall (aka retreating blade stall) is well known, I've never heard it referred as "dissymmetry of lift." Not in any textbook, paper or any talk I've attended. 208.106.125.63 (talk) 08:24, 28 November 2009 (UTC)

First most conventional helicopters would convert most lift to lateral thrust by tilting the main rotor into the direction of desired travel. Thus the faster you go the lower the percentage of lift AND dissymmetry possible. Plus the idea of dis-symmetry of lift is coupled to the idea that as lateral speed increases so does the rotational speed of the rotor. So if instead the speed of the rotor slows sufficiently then the dissymmetry of lift becomes a negligible effect (e.g. jet engine thrust as primary for lateral speed or other rotor speed reduction technology). As you near 90 percent tilt dissymmetry starts to disappear. If jet thrust is the main source of lateral thrust then in fact the helicopter starts becoming a regular airplane and is forced to slow its main rotor to avoid excessive lift. LOL - ultimately the old TV Airwolf trick or low speed mode of counterrotating rotors.

The standard tail rotor is the one place that dissymmetry of lift would really apply in full force, because the tail rotor is almost always perpendicularly aligned with the primary movement vector. But I believe that the ducted fan design was intended to solve that as the ducting shields the tail rotor from direct exposure to the "lateral" airflow.

So I suspect this is an affect that must be considered but not a direct primary limiting factor in modern high speed helicopter design as stated in the article. For the future the real challenge is the mechanical and thermal design and computer control of a supersonic rotor blade or ducted main rotor design. 69.23.121.234 (talk) 04:44, 14 December 2009 (UTC)

lift proportional to airspeed?

It is said in this page that lift created by an airfoil is proportional to the airspeed. But I think the dependance is quadratic as said in this page Lift. It does not change the conclusion anyway... —Preceding unsigned comment added by 84.75.182.173 (talk) 10:24, 21 January 2011 (UTC)