Spiral-based axial flow devices

A rotor of manufacture that can beneficially interchange kinetic energy with axial flows, consisting of a plurality of blades, each of which form continuously profiled, rigid spiral or ring bands, the progressive forward-portion axial sections of which have fixed chord-axis-wise orientation to the axial surface inclination of coaxial truncated cones-of-generation along said cones' progressive increments of axial azimuth and co-latitude coordinates, each said spiral bands being attached at azimuth variations around and axial location along an elongated aerodynamic hub of body-of-revolution that is itself attached to fixed supports which enable it to rotate, said continuously profiled bands combining means to eject boundary layer accumulations through tail section variations of disposition of convexity and concavity governed by a periodic function, such variations of convexity physically delineated by characteristic fluid-flow-relative expanding angles of isocline parabolas and axial-plane-relative angles of parabolas of maxima of chord-normal convexity, as well as by a subtended coaxial angle of constant azimuth increment defining the disposition of successive axial section maxima of convexity,

• whereby such rotors can efficiently interchange fluid momentum change with an impulse of tuning force generated by deflecting mass flows rates with low frictional dissipation and limited spanwise flow.

A rotating axial flow duct-rotor of manufacture, combining the function of controlling stream tube convergence or divergence with the function of acceleration or deceleration of axial flow as well as with the function of boundary layer transport, consisting of a plurality of blades that individually form continuously profiled, rigid spiral or ring bands, the progressive axial forward sections of which have fixed chord-axis-wise orientation to the axial-plane-relative surface inclination of coaxial truncated conoids-of-generation along said conoids' progressive increments of azimuth and axial co-latitude coordinates, said spiral bands being attached at azimuth variations around and axial location along an elongated aerodynamic body of revolution that is itself attached to fixed supports which enable it to rotate, allowing said rotating blade plurality's outer catenaries to progressively sweep out the outlines of a requisite duct shape, said continuously profiled bands combining means to eject boundary layer accumulations through tail section variations of convexity and concavity governed by a periodic function and said convexities physically delineated by characteristic helix-relative expanding isocline parabolas and axial-plane-relative parabolas of maxima of chord-normal convexity, as well as by a subtended axial angle of constant axial azimuth increment connecting said successive axial section maxima of convexity,

• whereby such a duct can impart measured radial accelerations or decelerations to converging or diverging peripheral flows and can therefore dispense with the expense and drag of a fixed duct, entrain greater mass flow rates per diameter of operation by reducing unwanted fluid tube expansion or contraction and thus can function to reduce or increase tip velocity, function to reduce frictional dissipation as well as function to limit spanwise flow due to planform variable sweep.