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, wherein the receding surface is planar, 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.