Sharp rotor

According to the inventor peter Sharp, this rotor uses both Magnus and Kramer effect. I forget how the Kramer effect works. That said the Sharp rotor can be an inflatable rotor. I obtained foam rotors and tested them. I found a good lift coefficient of 2-3.

Higher lift coefficients (until 7 and perhaps more) can be achieved and were experimented for a Flettner rotor, as shown on the figure 4: https://www.sciencedirect.com/science/article/pii/S0167610518307396 , but the drag coefficient is high, so the lift to drag ratio is below 3, as for the Sharp rotor. See the power consumption on the figure 13.