A system and method for orienting first and second reaction turbines relative to an axis of rotation responds to a fluid flow having a flow orientation axis. The fluid flow is received in a casement. The casement has first and second endplates situated parallel and spaced apart along the axis of rotation. A first half of the fluid flow drives the first reaction turbine to rotate with a first spin orientation in a plane perpendicular to the axis of rotation to produce a first torque about the axis of rotation. The second half of the fluid flow drives the second reaction turbine, offset from the casement plane relative to the first reaction turbine, with a second spin orientation opposite the first spin orientation to produce a second torque about the axis of rotation. The casement is oriented about the axis of rotation in response to the first and second torques.

FIELD OF THE INVENTION

This invention relates generally to turbine technology and, more specifically, to fluid-driven reaction turbines.

BACKGROUND OF THE INVENTION

The operation of reaction turbines is described by Newton's third law of motion (action and reaction are equal and opposite). In a reaction turbine, unlike in an impulse turbine, the nozzles that discharge the working fluid are attached to the rotor.

The acceleration of the fluid leaving the nozzles produces a reaction force on a turbine rotor, causing the rotor to move in the opposite direction to that of the fluid. The pressure of the fluid changes as it passes through the rotor blades. In most cases, a pressure casement is needed to contain the working fluid as it acts on the turbine; in the case of water turbines, the casement also maintains the suction imparted by the draft tube. Alternatively, where a casement is absent, the turbine must be fully immersed in the fluid flow as in the case of wind turbines.

A reaction turbine is most efficient when suitably oriented to the fluid flow. In the case, for example, of wind turbine applications, the shifting orientation of the driving wind causes fluctuating efficiency in exploiting the wind as an energy source. The most frequent means used to orient the turbines includes some form of vane in the fashion of farmyard windmill. Using a vane, however, has proven to be inefficient and achieves orientation slowly often lagging the actual orientation of the fluid flow.

Actuated orientation of turbine requires the use of rapidly performing processors and suitable sensors. Those algorithms generally use the output of the turbine using a phase-locked loop. Generally, these algorithms suffer from perennial searching loops overshooting the maxima in a manner characteristic of either under- or over-damped oscillatory systems. In either of the vaned or the actuated systems, searching inefficiencies can denigrate performance of reactive turbine as function of the available kinetic energy of the driving fluid.

There is an unmet need in the art for a self-directing turbine system efficiently deriving energy from a flowing fluid stream.

SUMMARY OF THE INVENTION

A system and method for orienting first and second reaction turbines relative to an axis of rotation responds to a fluid flow having a flow orientation axis. The fluid flow is received in a casement. The casement has first and second endplates situated parallel and spaced apart along the axis of rotation. A first half of the fluid flow drives the first reaction turbine to rotate with a first spin orientation in a plane perpendicular to the axis of rotation to produce a first torque about the axis of rotation. The second half of the fluid flow drives the second reaction turbine, offset from the casement plane relative to the first reaction turbine, with a second spin orientation opposite the first spin orientation to produce a second torque about the axis of rotation. The casement is oriented about the axis of rotation in response to the first and second torques.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A self-orienting casement pressure casement comprises a first and a second turbine spinning in opposite directions to produce generally balanced and opposing torques about an orientation axis. As a flow of fluid along a fluid flow vector drives the first and second turbines, imbalances occur between the loading of the first and second turbine. Generally these imbalances are the result of the orientation of the casement deviating from the orientation of the fluid flow vector. The resulting differences in torque between the first and the second turbines tends to reorient the casement to align with the fluid flow vector resulting in stable equilibrium as the imparted torque from the first and second turbines balance each other.

Referring toFIG. 1a, a cross-section of the orientable turbine casement10, the symmetry of the elements of the orientable turbine casement10about a casement plane14, is evident. The casement plane14is set forth to define a plane of symmetry and by design conveniently indicates the orientation of the casement10relative to an optimum orientation relative to the fluid flow vector5. The fluid flow vector5may represent either the flow of a compressible or noncompressible fluid such that the embodiment will function in air, water, seawater, and any other fluid. The casement10does not depend for its performance upon any inherent properties of either liquids or gasses.

An orientation axis23is contained in the casement plane14and passes through an endplate13at a point; the orientation axis23is generally perpendicular to the generally planar endplate13. The endplate13is shown in non-limiting exemplary form as circular but the shape of the endplate13is not a necessary feature. A round endplate13is shown to emphasize, in this exemplary embodiment, that the endplate13is configured to rotate about the orientation axis23in order to align the casement plane14with the fluid flow vector5as shown.

Suitably mounted on the endplate13to further form the casement10are casement outer walls18and casement inner walls19which, in concert with the endplates13in this exemplary non-limiting embodiment of the orientable casement10, form flow concentrators bilaterally symmetrically about the casement plane14. The casement plane14bisects the orientable casement10into a first casement half10ahaving a first turbine system11aand its mirror image, the second casement half10bhaving a second turbine system11b. In the exemplary embodiment, the first casement half10ais a precise mirror image of the second casement half10b, however, it is envisioned and suitably included in this disclosure that where, by virtue of a selected application, orienting the orientation axis horizontally in a fluid, differences in density of the fluid at the locations of the first and second turbine systems,11aand11b, might result in measurable differences in the performance between the first and second turbine systems11a,11b, in a fashion that slight differences in the dimensional geometry are necessary to balance the output of the first and second turbine systems. For this reason, first and second turbine systems11a,11bare substantially mirror images of each other, though not necessarily precise mirror images.

For purposes of this disclosure, the mirrored nature of the first turbine system11ato the second turbine system11b, thereby necessitating only that the first turbine system11abe fully disclosed to fully disclose the second turbine system11b. The first turbine system11adoes, by virtue of its mirror-image-ness rotates in the opposite direction to the second turbine system11b. The turbine rotor12of the first turbine system11amirrors the turbine rotor12of second turbine systems11bto such an extent that the turbine blades15of the first turbine system11aimpart a rotation to the rotor12that is opposite in orientation to that imparted by the turbine blades15to the rotor12in the second turbine system11b.

Concentrating on the first turbine system11a, the rotor12is a reaction rotor. As noted in the background, in a reaction turbine such as the first turbine system11a, acceleration of the fluid leaving the turbine blades15produces a reaction force on a turbine rotor12, causing the rotor12to move in the opposite direction to that of the fluid.

In the first turbine system11afluid enters the system with kinetic energy directed along the fluid flow vector5. An outer casement wall18, an inner casement wall19, and a plurality of pre-whirl vanes direct the fluid flow onto the rotor12at the rotor blades15causing the rotor12to rotate. Secondarily, the rotation of the rotor12in the fluid imparts a torque20tending to cause rotation about the orientation axis23. Because the torques20generated by each of the first turbine system11aand the second turbine system11btend to be in balance there is no resultant movement about the orientation axis and the casement10remains oriented by balance of the torques20. Due to the geometric relationship of the first and second torques20, the casement10rotates about the orientation axis23seeking to balance the torques20. The casement10tends to reorient in the direction of the greater torque exposing to a greater extent the lesser, in terms of volume flowing over the rotors12, of the first turbine system11aor the second turbine system11b. By such means, the casement10tends to self orient to balance the performance of the first turbine system11aand the second turbine system11b, thereby orienting the casement plane14to the fluid flow vector5.

Referring toFIG. 1b, a longitudinal section of first half casement10aincluding the first turbine system11a, excludes (for purposes of clarity) the outer casement wall18(FIG. 1a), the inner casement wall19(FIG. 1a), and the pre-whirl vanes21(FIG. 1a). The rotor12has rotor blades15that extend longitudinally substantially from the first endplate13to the second endplate13. The casement10ais oriented to receive the fluid flow (indicated by fluid flow vectors5) in parallel to the casement plane14. The escaping fluid is shown by fluid escape vectors6leaving the rotor12.

In this exemplary embodiment, turbine pivots24are situated and connect the endplates13by virtue of the pivot stators27and to the rotor12allowing the rotor12to rotate relative to the pivot stators27about the axis of rotation16in response to the fluid flow along the fluid flow vectors5. Rotation of the rotor12relative to the pivot stators27generates electricity by virtue of generator elements33attached to the rotor12rotating about the stator27. While not shown, the casement half10aincluding the endplates13are free to orient relative to the fluid flow5about the orientation axis23to maintain optimal orientation of the casement10.

Referring toFIG. 2a, a cross-section of a fluid catchment system demonstrates a non-limiting embodiment in a water turbine application. Tidal-power is the power achieved by capturing the energy contained in moving water mass due to tides. The orientable turbine casement10may be used in either of a riverine or a tidal application, though the tidal application is the more elaborate and therefore the subject of this disclosure. The riverine application differs only in that no barrage56need be present. For this reason, the fluid catchment system50described here includes the barrage56.

The barrage56is an artificial obstruction similar to a dam. The barrage56is hollow to enclose a flapper valve55on a valve pivot54. The barrage56is rounded to allow smooth overflow of the barrage56by a flooding tide at high tide. Where the height of the tide is less than that of high tide, the flapper valve56works to ratchet the flow of water60into the catchment system50. With each wave, the kinetic energy of each wave urges the flapper valve55into its open position. As the wave recedes, the head created by the standing water60urges the flapper valve55into sealing engagement against the barrage56.

The same head of the standing water60is converted into kinetic energy as the water flows through the funnel concentrator57according to the fluid flow vector5. The orientable turbine casement10orients itself according to the method set forth in the discussion above. As the water60flow through the orientable turbine casement10, the level of the water60drops resulting in a variable fluid flow vector5. Thus, the orientable turbine casement10assures the most efficient exploitation of the head created by the standing water60.

Referring toFIG. 2b, a plan view of the fluid catchment system, shows an alternate embodiment of the invention suitable for exploiting both tidal action and the self-orienting ability of the orientable turbine casement10. A channel is defined between a tidal basin (not shown) and an ocean inlet (not shown). Absent the catchment system50, water60carried on the inrushing tide flows through the channel to fill the tidal basin. As the tide recedes, water in the tidal basin flows in the reverse direction out of the tidal basin.

Interposing the orientable turbine casement10exploits the flow from through the channel to fill the tidal basin and from the tidal basin back out to the ocean. In this exemplary embodiment, a funnel is defined by a seawall51having the flapper valve55to modulate the effects of wave action within the catchment system50thereby assuring less variation in depth of the collected water60. With an onrushing tide, the water60is elevated above the level of water in the tidal pool. The rotors12of the orientable casement10are driven by the head the water60provides. By action of the rotors12, the orientable casement10orients itself to exploit the onrushing tide to generate power.

As the tide recedes, water trapped in the tidal pool rushes through the casement system50. Water flowing from the tidal pool to the lower level of water60within the seawall51drives the rotors12. By action of the rotors12, the orientable casement10reorients to exploit the reversed flow. The head is cyclically created in the fashion to drive the rotors.

FIG. 3is a shipboard use of the orientable turbine casement10used to provide motive force in a ship. A ship's hull72is driven through the water by generating electricity with the orientable casement10in multiple vertical masts. The lateral stability of the hull72allows the use of the orientable casement10both to provide a sail-like propulsion of the hull and by the further action of the rotors12to generate electricity.

As the rotors12spin and orient the orientable turbine casement10according to the wind direction relative to the hull72. While an auxiliary power unit75is also available to supply electricity in low-wind conditions, generally the spinning rotors12generate the power necessary to power the systems within the hull72through the power control panel78. As directed from the panel78, electricity is routed an electric motor81used to rotate a screw84providing propulsion to the hull72.