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Revolutionary or counter conventional aerodynamic principles

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Aircar

Well-Known Member
Joined
Feb 20, 2010
Messages
3,566
Location
Melbourne Australia
Moderator note:
These posts came from the Synergy-topic:
https://www.homebuiltairplanes.com/...-new-technology/10117-synergy-aircraft-5.html

But deserved a topic of their own.


Maybe the problem is that this thread has been labelled "Synergy aircraft" rather than what I took the underlying subject to have been -- namely 'revolutionary' or counter conventional aerodynamic principles that are claimed, and happen to be embodied in the design called Synergy ( John Mc Ginnis started his own thread quite a while ago on the EAA 365 forum-entitled "beyond streamlining ...... for the 21st century" which was a long and hard to understand 'build up' claiming wonderous new principles that didn't just apply known but advanced ideas but went beyond the normal physical understandings of aerodynamics as known by recognized qualified experts (rather than some rank amateur's misconceptions for comparison)

It has always been the hope that the experimental category would one day throw up new aerodynamic or other techniques and there is much to justify that hope from just looking at the history of science itself and the relatively recent emergence of aviation -- the Wright Brothers were relatively uneducated and persisted along with mostly other amateurs after the experts had either failed ( Langley, Maxim etc although Langley did fly his models successfully)or had declared human flight itself impossible (Lord Kelvin and others ) -- a little perspective might help here.

Serendipitous discovery is common in science and that is why you cannot argue with an experimental RESULT -- eg IF Sinha HAS demonstrated real major drag reduction then it is to be welcomed and examined in detail --he is either a master scammer or he actually believes in his findings and should be adopted rather than ignored just because it appears to be 'impossible' -- IF John McGinnis has opened a new principle in aerodynamics then I will be the first to congratulate him . The emphasis is on the word new though --I do not see that the performance claims he makes are all that extraordinary as yet ( he is possibly 'hiding' some sort of high lift flap system with the black underside of the wing --or a Goldschmied type airfoil -- the developed Cl max is not extraordinary but is higher than totally conventional wings will do -- there ARE ways to get two to three times as much lift from that size wing using things like spanwise blowing and enhanced vortex (using external power input but also possibly exhaust flows --not "defying Newton" or anything . ) all within published technology.

John has simply APPLIED known, albeit obscure, know how as far as I can see and has been uneccessarily obtuse in describing his 'new' technology in my view --even the terms and actual phrases he used were lifted from Goldschmied and Bushnel (eg the analogy of towing a canal barge appears in Golschmied's paper and Bushnel on open thermodynamic systems etc -- if it was a thesis you would be shot down for plagiarism in fact rather than awarded a patent --nevertheless homebuilt aviation stands condemned for NOT using the freedoms to experiment with relatively unorthodox aerodynamics when there is no disincentive as for certified aircraft or factory planes.

From what Autoreply stated I seem to get the idea that 100% laminar flow would be the ultimate possibility and --maybe I am wrong in this deduction -- the actual shape would then no longer matter ( all Cds becoming equal at the lowest value ) -- pressure recovery is then irrelevant . This is not true as far as I understand Goldschmied et al and only addresses skin friction rather than profile drag in toto.

I think that there is a misconception at work with Goldschmied's application to airships and ships where the relative wake size to the propeller are somewhat matched and this allows to reaccelerate the wake so that the momentum change is large while the kinetic energy left in the wake is small (acheived with air propellers by increasing the diameter way past any possible body wake )
 
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