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DONG090909 Conjecture when the rotor has forward speed

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Well-Known Member
Oct 25, 2016
GuangDong China
1. First guess
The conditions for the lift balance of the coaxial anti-propeller rigid double rotors are: the upper and lower rotors are in the same phase
Proof method:
Junior high school mathematics and physics: vector analysis of forces
2. Second conjecture (an extreme case of the first conjecture)
If the number of blades can be infinite , the lift balance of the upper and lower rotors can be achieved at every moment. a flying saucer

3. Background:
A. When I first saw the Sikorsky ABC rotor concept, I remembered: the differential compensation theory commonly used in electronics, I think its biggest benefit should be to reduce lift fluctuations.
B. I'm curious: why the great companies don't mention: Conditions for rotor lift balance. At least I can't search it. And it affect the direction in which humans resolve lift fluctuations
C. I estimate:
---Flexible rotor, it really doesn't make sense.
---The rigid rotor is subject to the influence of the few blades of the mainstream helicopter, which does not reflect the value (more blades, low flight efficiency)
D. I tried simple communication with aviation professionals on the mainland, at least they did not overturn my point of view.
E. Unfortunately: these two conjectures are an important aerodynamic basis for the aircraft I designed.

4. Therefore, I hope you can review my conjecture.