I am designing a fan blade which is attached to a generator. The unit will be submerged in water. The blade will be attached to the generator by a shaft. The device is semi-enclosed in a cylinder with the top and bottom open. The force of the waves will cause the propellor to spin. My question is: What types of forces will present on the shaft. I can think of the weight of the propellor and the torque caused by it spinning. Would the weight of the propellor be neglected since it is submerged underwater? Any response is appreciated. Thank you.