3 ms·
This does not explain the most obvious issue (or at least my most obvious issue): when going as fast as the wind, there is no wind anymore. The answer: at that
by koonsolo 5y ago
This does not explain the most obvious issue (or at least my most obvious issue): when going as fast as the wind, there is no wind anymore. The answer: at that point, your wheels are turning, and so you can get energy from your turning wheels, but not directly from the wind.
This is how I explain it in my head:
1. When going slower than the wind, the wind pushes you forward. Propeller at this point is useless.
2. When going as fast as the wind, the wheels will drive a propeller that pushes wind back (same as an airplane)
3. When going faster than the wind, all your energy will come from the turning wheels.
- DarmokJalad1701 5y ago> 3. When going faster than the wind, all your energy will come from the turning wheels. But why do the wheels keep turning in this scenario? Is there somehow a net-force on the back-side of the vehicle from the wind?
- atoav 5y agoForward momentum of the vehicle I guess.
- atoav 5y agoI think you are spot on. IMO it is just positive feedback: the faster you go the more wind is being pushed back by the propeller. At some point the system reaches a state of saturation or equilibrium (the wheels turning no longer can speed up the propeller enough to generate more push). This equilibrium is going back and forth between phases 2 and 3 as you described it. The thing that makes it a little bit hard to reason about is that all three components (wind, wheel, propeller) are interdependent and influence each other in a more or less fluid way. To me it feels similar like reasoning about active filter topologies.