Build your own HO229 WW2 German Jet Fighter!!

Discussion in 'Hangar Flying' started by Aerowerx, Jul 14, 2019.

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  1. Jul 25, 2019 #121

    Speedboat100

    Speedboat100

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    I know you Red are a protegee of mr Bowers...so I handle you with silk gloves.

    Have a good day !
     
  2. Jul 25, 2019 #122

    Red Jensen

    Red Jensen

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    Me with silk gloves? lmao...that's great.
     
  3. Jul 25, 2019 #123

    Aerowerx

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    Well, sort of. Maybe. Perhaps. It depends.

    If you design a flying wing (with no vertical surfaces) and then optimize it for yaw damping and to eliminate adverse yaw you will end up with something that looks a lot like a bell-shaped distribution. So in that respect bell-shaped could be thought of as "normal" for a flying wing! Knowing this, why not start out planning on the bell-shape? It will save A LOT of trial and error.

    And elliptical IS NOT close to perfect. It puts too much lift near the wing tips, which can cause a problem with wing tip stall, which can lead to spins. It also requires a heavier spar to handle the bending moment at the root. Remember bending moment = force x distance. Reduce the force at the wing tip and you reduce the bending moment at the wing root---->lighter spar required.
     
    Last edited: Jul 25, 2019
  4. Jul 25, 2019 #124

    Speedboat100

    Speedboat100

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    Very good point Aerowerx.

    Wing will fly:
     
    Last edited: Jul 26, 2019
  5. Jul 27, 2019 #125

    Speedboat100

    Speedboat100

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    Red,

    Explain us all the negative aspect of the flying wing the mittel effekt (or mittleren effekt as Reimar Horten put it) and how we can get rid of it in a good flying wing design !
     
    Last edited: Jul 27, 2019
  6. Jul 27, 2019 #126

    pictsidhe

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    Is this an exam?
     
  7. Jul 27, 2019 #127

    Aerowerx

    Aerowerx

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    From post #7 in this RC forum:
    And I don't think you can get rid of it. Besides, you want the stall (that is, maximum cl) to occur at about 30%-40% of the half span from the root.

    I also like this statement from post #4 of the same thread:
     
  8. Jul 27, 2019 #128

    Speedboat100

    Speedboat100

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    Now you spoiled all the fun of studying from Red.
     
  9. Jul 27, 2019 #129

    Speedboat100

    Speedboat100

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    Yes Red could have become the head of my wind turbine teams aerodynamical division...had he answered correctly.
     
  10. Jul 27, 2019 #130

    pictsidhe

    pictsidhe

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    Oh well, I suppose he will just have to put up with NASA work.
     
  11. Jul 28, 2019 #131

    Speedboat100

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    Yes...that amn't miserable either.
     

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  12. Jul 28, 2019 #132

    Urquiola

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  13. Jul 28, 2019 #133

    Urquiola

    Urquiola

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    No, I'd say this is a helping hand request. Salut +
     
  14. Jul 28, 2019 #134

    Speedboat100

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    Ludwig Prandtl was a busy man: https://www.kitplanes.com/prandtl-wing-goldschmied-fuselage/

    Red is here too: https://amablog.modelaircraft.org/amaeducation/2017/05/08/manned-prandtl/

    Dunne and Lippisch used a rudder: https://en.wikipedia.org/wiki/Tailless_aircraft
     
  15. Jul 28, 2019 #135

    Speedboat100

    Speedboat100

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    Mitteleffect explained by Al Bowers here at 26:00:
     
  16. Jul 28, 2019 #136

    Red Jensen

    Red Jensen

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    As amazing and prestigious as this sounds, I think I'll pass. :rolleyes: You will be happy to know however that we are doing some prop research as well.....
     
  17. Jul 29, 2019 #137

    Speedboat100

    Speedboat100

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    You might be surprised that scientists have discovered that a prop is very inefficient in a wind turbine...a H-Darreus type wind turbine can reach Cp 12% past Betz limit !

    My innovation based pitch controlled HD ( H-Darreius ) actually rews faster than anything in the history books so far...but it also endures more Gs than anyone has ever measured in a similar wind turbine before.

    Red...you could have become multi billionaire in this project.

    https://iopscience.iop.org/article/10.1088/1742-6596/753/2/022056/pdf

    Maybe you could shed this light into the wind turbine communities: Using the optimized pitch angle curve depicted in Figure 4a a converged power output, which is ≈12% higher than that of the Betz limit, is determined.

    I will do my doctorate degree about this..in the field of fluid dynamics.
     
    Last edited: Jul 29, 2019
  18. Jul 29, 2019 #138

    Aerowerx

    Aerowerx

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    What is the thing made of? So it can stand those G forces. Carbon fibre?
     
  19. Jul 29, 2019 #139

    Speedboat100

    Speedboat100

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    I figure there happens something else ( that sorta compensates the G forces )...what I am going to find out. This contraption is entirely outa wood..except some bolts, tubes and generator.
     
  20. Jul 29, 2019 #140

    pictsidhe

    pictsidhe

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    12% past theoretically possible?

    Somebody has screwed up somewhere, I somewhow doubt that it was Betz. His limit has been around a long time, and nobody has shown it to be wrong yet.

    Ye cannae change the laws of physics, Jim!
     
    Last edited: Jul 29, 2019

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