Fluid propulsion system

A device for inducing fluid flow relative to itself, comprising:

• a. a body configured to be brought into contact with a fluid, the body possessing:
• i. a fore end, an aft end, and an axis of rotation about which the body is configured to rotate, and
• ii. a central hub possessing torque acceptance means configured to accept and convey a torque from a torque generator to the body, and where the torque so conveyed manifests as a rotational velocity of the body of the device about the axis of rotation and driving every point on the surface of the body with a rotational motion in a plane perpendicular to the axis of rotation,
• iii. at least one monolithic cantilevered lobe extending radially away from the axis of rotation, the lobe possessing one proximal end affixed to the hub, and a distal end, with the lobe further possessing:
• 1. A receding surface inclined with respect to the axis of rotation such that the receding surface recedes away from the fluid as the body rotates, and
• 2. A rump surface that encloses the rest of the lobe, and
• 3. Where the receding surface and the rump surface intersect, forming there a receding edge, and
• 4. Where the receding edge is bordered by an adjacent rump surface that:
• a. from every point on the receding edge extends axially aft along the rump surface from the receding edge at least an axial thickness, and
• b. from every point on the receding edge extends around the rump surface from the receding edge in the direction of rotational motion at least a transverse thickness, and
• iv. where, providing a fluid in contact with the body, the rotational velocity of the body about axis of rotation results in a counter-flow over the device, and the adjacent rump surface being so configured such that counter-flow over the adjacent rump surface
• a. has no radial component, and
• b. has a component in the direction opposite the direction of rotational motion, so that the counter-flow flows past the receding edge at an angle having little or no radial component and with a non-zero component in the direction opposite the rotational motion, and
• v. where the receding surface, being pulled away from the fluid by the rotational velocity thus induces a low-pressure region directly over the receding surface such that the low-pressure region travels with the receding surface as the body rotates with respect to the fluid, and
• vi. where the low-pressure region, being directly adjacent to the counter-flow flowing past the receding edge, thus generates a bound edge vortex over a substantial portion of the receding surface, where the bound edge vortex rotates in the opposite direction as the rotational velocity, and
• vii. where the bound edge vortex further reduces the fluid pressure over the receding surface, and,
• viii. an inclination of the receding surface relative to the axis of rotation causes the vortex to have a substantial aft-directed axial component of fluid flow that generates forward thrust on the body of the device.