Arvel Gentry () was an aerodynamicist. He had a plentiful professional career including having been involved in aerodynamic’s research on the. The Origins of Lift – By Arvel Gentry (January ). July 24, at PM. [ Esta es una copia de una página web que ya no está disponible en la red. Some changes to the Goat Island Skiff sail and how to use leach ribbons or tufts for more accurate sail trimming and steering to reach greater sailing efficiency.

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Arvel Gentry – Sailing Anarchy – Sailing Anarchy Forums

Also on plane wings you have something called angle of attack AOA, that being the angle of the chord of the wing a line from the leading srvel to the trailing edge relative to the angle of the air flow If AOA exceeds degrees the wing stalls and ceases to produce lift.

Birds could not arve, airplanes would not fly, and sailboats would not sail! I want to resolve this in my own mind before I get to my first sailing classroom session in June so that I can keep my mouth shut and not contradict the teacher when she repeats the standard explanation. For theglider pilot, it is almost everything but he needs help to get aloft.

In their search for lighter and lighter airfoils, the experimenters finally killed some local flies, or so they claimed, and the investigation gentrj known as the flies’-wings experiment. This happens when the flow on bothsides of the trailing edge have equal speeds and pressures. I have a complete copy of his website archived, which I downloaded several years ago.

Condolences to your family. What is thefundamental explanation for the generation of lift? This allows us to get at the real essence of the origins oflift. The circulation flow field causes alarge amount of air to flow on the top lee side of the airfoil.


Join or Log Into Facebook. He was a wonderfully insightful scientist, and a much loved and respected mentor. If the fluid has no viscosity, ouraerodynamic theories indicate that we would have no lift and nodrag.

Unfortunately, he passed away on June 1st, after a battle with Parkinson’s. The streamlines are equally spaced. In the caseof a sail, genttry would bend the leading edge of the airfoil down intothe flow in order to avoid flow separation. The fundamentals of lift generation are presented with emphasis on their usefulness for understanding the flow around sails on a sailboat.

Arvel Gentry Archives – Really Simple Sails

First, I would like thank you for keeping the web connection for my father. Hentry is a special mathematical solution where a second flow rotates around the airfoil.

Are you intending to make all of Arvel Gentry’s publications available? They also provided more detail as to howcirculation fields are important in properly understanding multielementairfoils and, therefore, how our sails work.

It is very nice of you to make contact with this forum, welcome! In our 2-D case, the circulation flowfield causes the air out in front gehtry the airfoil to be directed upwardaround the airfoil and then back down to about the same level asit started out in front. I’m not tech savvy enuff to check this hentry, but believe it true.

Find My Loft Find your local loft below. Tietjens, Fundamentals of Hydro- andAeromechanics. The emphasis here ison understanding more of the details of the airflow than is taughtto the beginning pilot.

Non-lifting flow around a flat plate. The superfluid was pulled through vertically. The streamlines shown in Figures 2, 4, and 5 werecalculated using conformal transformations as devisedoriginally by Joukowski [4, p46].

This gives the speed differential, top to bottom, the pressure differential, and then the lifting force. Thursday, November 04, I was basically bottle fed on Kittiwake and other boats and continue to sail today. Log in or Sign up. What if there are two flows — rather than one — around an airfoil like a sail, wing, keel, or rudder?

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There is a fluidwith zero viscosity, super-cooled helium [10]. One very enjoyable book wasby E. His discoveries in the 60s and 70s on the various america’s cup efforts led the the mast section shapes we see everywhere for non-rotating masts: World of Sailing will remember him with affection.

Gentry was instrumental for winning and keeping the America’s Cup

Lower pressureson top and higher pressures on the bottom mean that the airfoilnow has lift. We promise to call as quickly as possible, but at some times we may be out sailing.

His daughter Kimberly has strong interest on keeping his legacy available for sailors of all countries. I’ll send you a private message for us to keep in contact.

Arvel Gentry’s site

Looking for a quote? Thejib helps the mainsail by reducing the peak suction pressure nearthe mast so the sail will not stall.

The circulationfield emerges as the starting vortex is formed. However, the merging of two different flow fields is morecomplicated than the simple boat apparent wind problem. It used circulation concepts todiscover how the circulation flow fields about multiple sailsinteract causing even more air to flow on the lee side of the jib,while at the same time helping prevent the mainsail fromstalling.

It works much better than ovals or elliptical sections. Everyone who sails should read his articles from the s and 70s. Where thestreamlines get farther apart such as on the lower surface, theflow slows down and the pressures get higher.

The two circulations appose each other inthe slot between the sails and add to each other in the region to leeof the jib.