FLUID FLOW CONTROL PROVIDING INCREASED ENERGY EXTRACTION
Systems and methods configured to control ambient fluid flow for increased energy extraction using a turbine are disclosed. In various examples, a system can include a convergent nozzle configured to receive and accelerate an ambient flow of fluid and a turbine including one or more rotor blades. The convergent nozzle can include a configuration having a ratio of a nozzle inlet area to a nozzle outlet area between about 1.5:1 to about 10:1, inclusive. An interior nozzle surface can include one or more contours aligned with a direction of the ambient flow of fluid. The convergent nozzle can include apertures in a region near a nozzle outlet. The apertures can be selectively controlled to draw additional fluid flow into the accelerated flow to avoid excessive stress on turbine components. The rotor blades can have a length equal to or slightly greater than a radius of the nozzle outlet.
This non-provisional patent application claims the benefit of priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application Ser. No. 61/387,330, entitled “SYSTEMS AND METHODS TO CONTROL FLUID FLOW FOR ENERGY EXTRACTION,” (Attorney Docket No. 3293.001PRV), filed on Sep. 28, 2010, which is hereby incorporated by reference in its entirety.
TECHNICAL FIELDThis patent document pertains generally to the control of fluid flow. More particularly, but not by way of limitation, this patent document pertains to systems and methods configured to control fluid flow for increased energy extraction.
BACKGROUNDEnergy extraction systems and methods utilizing liquid or gaseous fluid flow are known. For example, wind turbines convert kinetic energy of wind flow into mechanical work for applications such as power generation. Similarly, hydro turbines extract energy from flowing water for generating power or driving machinery. These turbines are typically dependent on the ambient fluid flow velocity at a turbine interface, and more particularly, at rotor blades of the turbines.
The quantity of energy available for capture in existing turbines is generally proportional to a cross-sectional area where the ambient fluid flow and rotor blades interact. Noteworthy, however, is that the cost of turbines increases and material requirements become more rigorous as rotor blade size increases.
Existing turbines deliver electric power to a grid system at times when ambient flow conditions are favorable to generating electricity, independent of whether there is user demand for the electricity. The turbines require a minimum ambient fluid flow velocity to operate and have a maximum tolerable fluid flow velocity, beyond which turbine components experience stresses posing a significant risk of failure. As a preventative measure, existing turbines are often shutdown when ambient fluid flow velocity is high and poses a risk of failure.
OVERVIEWThe present inventor has recognized that the relationship between fluid flow velocity and kinetic energy available for extraction is cubic, thereby elevating the desirability of fluid flow velocities greater than typical ambient flow velocities, the risk of component failure notwithstanding. The present inventor has further recognized, among other things, that energy extraction improvements can be realized by providing and using one or more of: (i) a convergent nozzle configured to receive and accelerate an ambient flow of fluid to a higher velocity prior to rotor blade reception, (ii) selectively controllable apertures near a nozzle outlet serving to lower or otherwise modulate, if needed, the velocity of an accelerated fluid flow at the rotor blades, (iii) a duct external to or within the convergent nozzle to create zones with differing fluid (e.g., airflow) velocities at the nozzle outlet, or (iv) rotor blades having a size, shape, or contour that is configured to extract greater usable energy at higher fluid flow velocities. Further yet, the present inventor has recognized that storage of turbine-captured energy until there is user demand enhances the value of turbine systems.
A system can include a convergent nozzle configured to receive and accelerate an ambient flow of fluid and a turbine including one or more rotor blades. The convergent nozzle can include a configuration having a ratio of a nozzle inlet area to a nozzle outlet area between about 1.5:1 to about 10:1, inclusive. An interior nozzle surface can include one or more contours aligned with a direction of the ambient flow of fluid. The convergent nozzle can include apertures in a region near a nozzle outlet. The apertures can be selectively controlled to draw additional fluid flow into the accelerated flow to avoid excessive stress on the turbine components. The rotor blades can have a length equal to or slightly greater than a radius of the nozzle outlet. Optionally, additional control over fluid flow can be provided using a cylindrical or convergent duct positioned within the convergent nozzle or an external annular airfoil ring positioned near the nozzle inlet or the nozzle outlet.
Control, extraction, and storage of the energy captured by the system can be achieved using hydraulic pumps, motors, or accumulators to defer electric power generation until user demand calls for it. A solar energy receiver can be used to capture additional energy and transmit the energy in the form of heat to a heat exchanger incorporated within the accumulator. The accumulator can compound the stored energy from the turbine system, using heat from the solar energy receiver to increase stored power, and optionally, waste heat from an exothermic process prior to being converted to electricity.
To better illustrate the systems and methods disclosed herein, a non-limiting list of examples is provided here:
In Example 1, a system comprises a convergent nozzle configured to receive and accelerate an ambient flow of fluid and a turbine including a rotor, with the rotor configured to convert kinetic energy of the accelerated flow of fluid into mechanical energy suitable to drive an energy extraction device.
In Example 2, the system of Example 1 is optionally configured such that the energy extraction device includes an electric generator or a hydraulic pump.
In Example 3, the system of any one or any combination of Examples 1 or 2 is optionally configured such that the convergent nozzle includes a configuration having a ratio of a nozzle inlet area to a nozzle outlet area between about 1.5:1 to about 10:1, inclusive.
In Example 4, the system of any one or any combination of Examples 1-3 optionally further comprises a platform configured to align the convergent nozzle and the rotor with a direction of the ambient flow of fluid.
In Example 5, the system of Example 4 is optionally configured such that an interior surface of the convergent nozzle includes a contour configured to be aligned with the direction of the ambient flow of fluid, the contour being defined using a reference line extending a length of the convergent nozzle, from a focal point of a nozzle inlet to a focal point of a nozzle outlet, with a reference point being about one half the distance along the reference line, a circumference of the interior surface of the convergent nozzle at each point, LRx, along the reference line being defined by,
Circumference=2π(RO+(C/2)+C*[(LRx*|LRx|)]/L2IO) and
Intended Factor of Acceleration=((2C/RO)+(C2/R2O))+1, where LRx is a positive amount if, from the reference point, the point at which the circumference is being determined is the distance along the reference line starting at the reference point in a direction toward the nozzle inlet, and LRx is negative where it is the distance along the reference line from the reference point in a direction toward the nozzle outlet, RI is the radius of the convergent nozzle at the nozzle inlet, RO is the radius of the convergent nozzle at the nozzle outlet, C is the difference RI-RO, and LIO is the length of the convergent nozzle determined along the reference line.
In Example 6, the system of any one or any combination of Examples 1-5 optionally further comprises or more ducts positioned within the convergent nozzle, with the ducts configured to create zones with a differing fluid velocity at a nozzle outlet.
In Example 7, the system of any one or any combination of Examples 1-6 is optionally configured such that the convergent nozzle includes a material selected from the group consisting of: aramid, liquid crystal polymer, ultra-high strength polyethylene, and carbon fiber.
In Example 8, the system of any one or any combination of Examples 1-7 is optionally configured such that the rotor includes one or more blades having a length about equal to or slightly larger than a radius of a nozzle outlet.
In Example 9, the system of Example 8 is optionally configured such that at least one of the one or more blades includes a blade tip turned at an angle to a longitudinal extension of the corresponding blade, the angle oriented in a direction toward an airfoil surface experiencing lift.
In Example 10, the system of Example 8 is optionally configured such that at least one of the one or more blades includes a blade having a plate positioned perpendicular to a longitudinal extension of the corresponding blade at the tip and at such other places along the span of the blade where it is desirable to inhibit fluid flow in the span-wise direction.
In Example 11, the system of any one or any combination of Examples 8-10 is optionally configured such that at least one of the one or more blades includes a wedge-like shape on a leading edge of an airfoil to reduce vortices at a blade tip.
In Example 12, the system of any one or any combination of Examples 8-11 is optionally configured such that an asymmetric camber of the one or more blades becomes more symmetric with respect to each blade's chord with the increasing distance away from a rotor hub until it is substantially symmetric near a blade tip, and wherein a length of the chord gradually increases with distance away from the hub.
In Example 13, the system of Example 12 is optionally configured such that the camber, the length of the chord, and an angle with respect to a plane of rotation of each blade is variable, in a continuous or a discontinuous manner, to correspond to a fluid velocity at the nozzle outlet created by one or more ducts positioned with an interior surface of the convergent nozzle or an external annular ring, having airfoil characteristics, positioned about a circumference of a nozzle inlet or the nozzle outlet.
In Example 14, the system of any one or any combination of Examples 12 or 13 is optionally configured such that the rotor hub includes an annular disc centered on a shaft driving the energy extraction device, and the one or more blades are adjustably coupled to the hub in such a way as to allow for modification of an attack angle of each blade's airfoil.
In Example 15, the system of any one or any combination of Examples 8-14 is optionally configured such that the one or more blades are directly or indirectly coupled to a shaft driving the energy extraction device using a rope of inelastic material, with the rope configured to redirect rotational forces on the one or more blades.
In Example 16, the system of any one or any combination of Examples 8-15 optionally further comprises an external annular ring, having airfoil characteristics, positioned about a circumference of the nozzle inlet or the nozzle outlet.
In Example 17, the system of Example 16 is optionally configured such that the airfoil includes a greater circumference on a leading inlet edge than on a trailing outlet edge and is positioned measured perpendicularly from the nozzle outlet at a distance approximately equal to its camber.
In Example 18, the system of any one or any combination of Examples 1-17 is optionally configured such that the convergent nozzle includes one or more apertures in a region near a nozzle outlet.
In Example 19, the system of Example 18 is optionally configured such that the one or more apertures are selectively controllable and, as the accelerated flow of fluid reaches or exceeds a preselected velocity, the apertures are opened to draw additional fluid flow into the accelerated fluid flow and modulate such accelerated flow to avoid excessive stress on the rotor.
In Example 20, a method comprises accelerating an ambient flow of fluid, including funneling the ambient flow of fluid into and through a convergent nozzle to a rotor of a turbine and driving an energy extraction device, which includes one or both of an electric generator or a hydraulic pump.
In Example 21, the method of Example 20 optionally further comprises transmitting power captured by driving the hydraulic pump to a hydraulic accumulator or a hydraulic motor attached to the electric generator.
In Example 22, the method of Example 21 optionally further comprises capturing heat energy from the sun or waste heat from an exothermic process and transmitting the heat energy to the hydraulic accumulator using a heat transfer fluid and a heat exchanger.
In Example 23, the method of Example 22 optionally further comprises transmitting energy from the hydraulic accumulator to a central system including one or more hydraulic motors attached to one or more electric generators.
In Example 24, the method of any one or any combination of Examples 20-23 is optionally configured such that funneling the ambient flow of fluid into and through the convergent nozzle includes accelerating the ambient flow of fluid at a ratio between about 2.5:1 to about 7:1, inclusive.
In Example 25, the method of any one or any combination of Examples 20-24 optionally further comprises positioning the convergent nozzle on a platform, including rigidly securing the convergent nozzle to the platform and mounting the platform to a tower such that the convergent nozzle and platform orientate a nozzle inlet with a direction of the ambient flow of fluid.
In Example 26, the method of any one or any combination of Examples 20-25 is optionally configured such that accelerating the ambient flow of fluid includes accelerating an ambient flow of wind or an ambient flow of water.
In Example 27, the method of any one or any combination of Examples 20-26 optionally further comprises coupling one or more rotor blades to a hub centered on a drive shaft of the energy extraction device, including enabling rigging affixed to the hub and between individual rotor blades to transmit angular forces on the blades to the hub.
In Example 28, the method of Example 27 is optionally configured such that coupling the one or more rotor blades to the hub includes coupling the rotor blades to the hub in a range from (a) each blade being perpendicular to the hub at the point of connection to (b) each blade being displaced up to 0.10 radians from a tangential point at which the blade extends perpendicularly.
In Example 29, the method of any one or any combination of Examples 20-28 optionally further comprises coupling one or more rotor blades to a hub mounted on a releasable roller clutch, with the roller clutch, when engaged, powering a drive shaft coupled to the energy extraction device.
In Example 30, the system or method of any one or any combination of Examples 1-29 is optionally configured such that all elements or options recited are available to use or select from.
These and other examples, advantages, and features of the present systems and methods will be set forth in part in the following Detailed Description. This Overview is intended to provide non-limiting examples of the present subject matter; it is not intended to provide an exclusive or exhaustive explanation. The Detailed Description is included to provide further information about the present systems and methods.
In the drawings, like numerals can be used to describe similar components throughout the several views. Like numerals having different letter suffixes can be used to represent different instances of similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.
The present subject matter provides systems and methods for extracting energy from flowing fluids by accelerating or otherwise controlling such fluid flow to a higher or more ideal velocity prior to being received at a turbine interface, and more particularly, at one or more rotor blades of the turbine. By establishing control over the fluid flow prior to extracting kinetic energy, the systems and methods can optimize fluid flow velocity at the point of extraction and moderate fluctuations in the ambient dynamics of the fluid, particularly those of relative direction and velocity.
In various examples, the system can include a wind turbine (e.g., a horizontal-axis wind turbine) and a convergent nozzle configured to orientate and accept on-coming ambient wind flow. In other examples, the system can include a water or hydro turbine and a convergent nozzle configured to orientate and accept on-coming ambient water flow. A decreasing circumference of the convergent nozzle causes the speed of the wind or water flow to increase until it is received by the wind or water turbine. In some examples, a modified form of the convergent nozzle can be used with a modified form of a conventional turbine. These modifications can include one or more of: (i) a reduction of the turbine dimensions relative to the expected power output to decrease a rotor blade swept area, (ii) changes in the placement of the rotor and the addition of rigging to extend means of redirecting the linear fluid flow force into rotational energy, (iii) modification of rotor blade shapes, as enabled by the rigging and reduced relative dimensions, (iv) the use of nozzle outlet apertures to introduce additional mass into the accelerated fluid flow to reduce the flow's velocity while maintaining the mass flow rate, as well as mitigate drag sources associated with the expected component velocities, and (v) the use of ducts external to or within the nozzle to create zones of differing fluid velocities at the nozzle outlet.
A platform or carriage 118 can be used to support and facilitate orientation of the convergent nozzle 104. In some examples, the platform 118 can be connected atop the tower 106 using a pivot connection joint. The pivot connection joint can allow the platform 118 to align the convergent nozzle 104 and the one or more rotor blades 114 with a direction of the ambient fluid flow.
A ratio of the area of a nozzle inlet 208 to that of the nozzle outlet 210 can establish the degree of fluid flow acceleration. In an example, the convergent nozzle 204 includes a configuration having a ratio of the nozzle inlet 208 area to the nozzle outlet 210 area between about 1.5:1 to about 10:1, inclusive. In an example, the ratio of the nozzle inlet 208 area to the nozzle outlet 210 area is between 2.5:1 to 7:1. The convergent nozzle can include a material selected from the group consisting of: aramid, liquid crystal polymer, ultra-high strength polyethylene, and carbon fiber, for example.
Each of the contours 350, 352, 354 can be symmetrical about a nozzle axis so as to form a circular cross-section and can be oriented in a direction of an ambient flow of fluid. In particular,
The contours 350, 352, 354 of the interior contoured surface 112 of the convergent nozzle 104, 204 can be defined using a reference line extending a length of the nozzle, from an axial focal point of a nozzle inlet to an axial focal point of a nozzle outlet, with a reference point being about one half the distance along the reference line. The contours 350, 352, 354 can be truncated at a location before the reference point, at the reference point, or after the reference point. A circumference of the interior contoured surface 112 of the convergent nozzle 104, 204 at each point along the reference line, the circumference at Lp can be defined by:
Circumference=2π(RO+(C/2)+C*[(LRx*|LRx|)]/L2IO) (Equation 1)
and
Intended Factor of Acceleration=((2C/RO)+(C2/R2O))+1 (Equation 2),
where LRx is a positive amount if, from the reference point, the point at which the circumference is being determined is the distance along the reference line starting at the reference point in a direction toward the nozzle inlet, and Lp is negative where it is the distance along the reference line from the reference point in a direction toward the nozzle outlet, RI is the radius of the convergent nozzle at the nozzle inlet, RO is the radius of the convergent nozzle at the nozzle outlet, C is the difference RI-RO, and LIO is the length of the convergent nozzle determined along the reference line.
Because of the dynamics of fluid flow at the nozzle outlet 410, developed by the convergent nozzle 404, the rotor blade 414 configuration can be tailored to expected fluid flows, including fluid velocities, apparent angles, and expected turbulence around each blade's airfoil. A rotor hub 450 can include an annular disc centered on a shaft driving an energy extraction device (e.g., an electric generator or a hydraulic pump). The rotor blades 414 can be adjustably coupled to the hub 450 in such a way as to allow for modification of an attack angle of each blade's airfoil. In an example, the coupling between the rotor blades 414 and the hub 450 can include a rope of inelastic material, which can be configured to redirect rotational forces of the blades 414. In an example, the coupling between the rotor blades 414 and the hub 450 ranges from (a) each blade being perpendicular to the hub at the point of connection to (b) each blade being displaced up to 0.10 radians from a tangential point at which the blade extends perpendicularly. The hub 450 can be mounted on a releasable roller clutch that, when engaged, powers the drive shaft of the energy extraction device.
A leading edge of an airfoil can include a wedge-like shape to reduce vortices at or near the blade tip 552. The camber, the length of the chord, and an angle with respect to a plane of rotation of the rotor blade 514 can be adjustable, in a continuous or a discontinuous manner, to correspond to a fluid flow velocity at a convergent nozzle outlet. The angle of attack (e.g., the angle between the chord length 530 and the apparent wind direction as the rotor blade 514 is rotating through the fluid flow during operation) can be based on the ratio of a nozzle inlet to a nozzle outlet of a convergent nozzle.
The convergent nozzle 704 can be mounted using a frame 790 consisting of side supports 772 attached to the platform central beam 718 near each of its ends by cross beams 774, 776. The cross beams 774, 776 can function to keep the convergent nozzle 704 in line with the beam 718 and all other mounted components. In some examples, the front cross beam 774 is substantially vertical to the ground and the rear cross beam 776 is slanted at about a 30° angle from vertical. The platform central beam 718 can rest on and attach to a pivot 796, and the cross beams 774, 776 can be attached to the beam 718 fore and aft of the pivot 796 so as to effectively deliver the torque for yaw control to the full system 700. Mounted at each end of the side supports 772 can be a frame arch to which the ends of the convergent nozzle 704 can be attached. In some examples, a first frame arch 792 is positioned at the nozzle inlet and a second frame arch 794 is positioned at the nozzle outlet. A system of braces can extend from the side supports 772 to the top of the arches 792, 794 at the front and back of the convergent nozzle 704.
In this example, the one or more ducts 1260 positioned within the interior surface 1262 of the convergent nozzle 1204 can include an inner duct 1268 at least partially nested within an outer duct 1270. The ducts 1268, 1270 can be located in an approach to and/or at a throat of the convergent nozzle 1204, thereby enabling the alternation of fluid flow velocities directed at sections of the rotor blades 1214. The inner duct 1268 can include a cylindrical shape having parallel slides. The parallel sides can be retracted 1268A when an ambient fluid flow is of a desirable velocity, or can be partially 1268B or fully extended 1268C when the ambient fluid flow is slower than desired. The extension of the parallel sides can increase a degree of flow acceleration in the nozzle outlet zones further from the central axis 1266. The inner duct 1268 can, for example, include a radius of between about 0.15 and about 0.30 times the radius of the inlet of the convergent nozzle 1204 and can be extended or telescoped toward the inlet 1208. Optionally, one of more additional ducts with, for example, a radius between about 0.25 and about 0.40 of the next inner-most duct can be included. The additional ducts can be capable of expansion such that an inlet 1208 area is greater than an outlet 1210 area and thus, capable of modifying the fluid flow velocity at the outlet to an extent different from other zones at the convergent nozzle outlet 1210. The one or more ducts 1260 can change in shape either by extension toward a convergent nozzle 1204 inlet plane or by increasing or decreasing a circumference of the duct inlet or both.
The internal outer duct 1270 can include a convergent configuration having an inlet-to-outlet ratio similar to that of the primary convergent nozzle 1204. The diameter of outer duct 1270 can be increased to alter the relative increase in fluid flow velocities of the outer two zones—increasing that of the inner zone and decreasing that of the outer zone in the expanded position. The outer duct 1270 can be moved along the axis 1266, thereby modifying an area of the two annular zones—a first at the inlet of the duct 1270 and a second at the outlet of the duct 1270.
The external annular ring 1264 can enclose the one or more rotor blades 1214, thereby guiding air across the blade tips 1252, minimizing vortex formation, and providing for greater consistency of fluid flow on the rotor blades 1214. The external annular ring 1264 can include a greater circumference on a leading inlet edge 1272 than a trailing outlet edge 1274. The external annular ring 1264 can be positioned from the convergent nozzle outlet 1210 at a distance approximately equal to its camber. The external annular ring 1264 can be positioned in the region of the nozzle outlet 1210 such that the components at least partially overlap. An area of the overlap formed by the leading inlet edge 1272 of the external annular ring 1264 and the nozzle outlet 1210, on a plane that is perpendicular to the direction of fluid flow, can be greater than an area formed by the non-overlapping portions of the external annular ring 1264. The external annular ring 1264 can extend beyond the plane of rotation of the system's rotors 1214, with the sides of the external annular ring 1264 being perpendicular to the plane at that point and thereafter becoming divergent.
In some examples, an external annular ring is additionally or alternatively positioned near a nozzle inlet 1208 (see, e.g.,
In the example of
Similar to the capture of heat energy from the sun and transmission to the hydraulic accumulator, a system can be configured to capture waste heat from an exothermic process and transmit the heat energy to the hydraulic accumulator 1536 using a heat transfer fluid and a heat exchanger.
Closing Notes:
The velocity or strength of ambient wind or water flow at a location can vary, and an average velocity or strength value of the ambient fluid flow can provide an indication of the amount of energy a typical wind or hydro turbine can produce there. The present systems and methods can advantageously enhance ambient fluid flows, while also modulating velocities at a turbine-defined upper end of a fluid velocity range. This fluid flow enhancement and control can, among other things, increase turbine productivity and reliability, as well as provide for lower start-up speeds and reduced operating costs relative to conventional turbines.
The present systems and methods can employ various components on a coordinated basis to establish the enhanced degree of control over the ambient flow of fluid prior to such fluid's interaction with a wind or hydro turbine. In various examples, the present systems and methods can be adapted or retrofitted to function with one or more components of existing turbines. Through use of the present systems and methods, existing turbines can be made more compact by, among other things, reducing rotor blade length without compromising on energy extraction capabilities.
The above Detailed Description includes references to the accompanying drawings, which form a part of the Detailed Description. The drawings show, by way of illustration, specific embodiments in which the present systems and methods can be practiced. These embodiments are also referred to herein as “examples.”
The above Detailed Description is intended to be illustrative and not restrictive. For example, the above-described examples (or one or more elements thereof) can be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. Also, various features or elements can be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter can lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.
In this document, the terms “a” or “an” are used to include one or more than one, independent of any other instances or usages of “at least one” or “one or more.” In this document, the term “or” is used to refer to a nonexclusive or, such that “A or B” includes “A but not B,” “B but not A,” and “A and B,” unless otherwise indicated. In this document, the terms “about” and “approximately” are used to refer to an amount that is nearly, almost, or in the vicinity of being equal to a stated amount.
In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended; that is, a system, kit, or method that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms “first,” “second,” “third,” and so forth are used merely as labels, and are not intended to impose numerical requirements on their objects.
The Abstract is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
Claims
1. A system, comprising:
- a convergent nozzle configured to receive and accelerate an ambient flow of fluid; and
- a turbine including a rotor, the rotor configured to convert kinetic energy of the accelerated flow of fluid into mechanical energy suitable to drive an energy extraction device.
2. The system of claim 1, wherein the energy extraction device includes an electric generator or a hydraulic pump.
3. The system of claim 1, wherein the convergent nozzle includes a configuration having a ratio of a nozzle inlet area to a nozzle outlet area between about 1.5:1 to about 10:1, inclusive.
4. The system of claim 1, further comprising a platform configured to align the convergent nozzle and the rotor with a direction of the ambient flow of fluid.
5. The system of claim 4, wherein an interior surface of the convergent nozzle includes a contour configured to be aligned with the direction of the ambient flow of fluid, the contour being defined using a reference line extending a length of the convergent nozzle, from a focal point of a nozzle inlet to a focal point of a nozzle outlet, with a reference point being about one half the distance along the reference line, a circumference of the interior surface of the convergent nozzle at each point, LRx, along the reference line defined by,
- Circumference=2π(RO+(C/2)+C*[(LRx*|LRx|)]/L2IO) and
- Intended Factor of Acceleration=((2C/RO)+(C2/R2O))+1, where LRx is a positive amount if, from the reference point, the point at which the circumference is being determined is the distance along the reference line starting at the reference point in a direction toward the nozzle inlet, and LRx is negative where it is the distance along the reference line from the reference point in a direction toward the nozzle outlet, RI is the radius of the convergent nozzle at the nozzle inlet, RO is the radius of the convergent nozzle at the nozzle outlet, C is the difference RI-RO, and LIO is the length of the convergent nozzle determined along the reference line.
6. The system of claim 1, further comprising one or more ducts positioned within the convergent nozzle, the ducts configured to create one or more zones with a differing fluid velocity at a nozzle outlet relative to an adjacent zone.
7. The system of claim 1, wherein the convergent nozzle includes a material selected from the group consisting of: aramid, liquid crystal polymer, ultra-high strength polyethylene, and carbon fiber.
8. The system of claim 1, wherein the rotor includes one or more rotor blades having a length about equal to or slightly larger than a radius of a nozzle outlet.
9. The system of claim 8, wherein at least one of the one or more rotor blades includes a blade tip turned at an angle to a longitudinal extension of the corresponding rotor blade, the angle oriented in a direction toward an airfoil surface experiencing lift.
10. The system of claim 8, wherein at least one of the one or more rotor blades includes a blade tip having a plate positioned perpendicular to a longitudinal extension of the corresponding rotor blade.
11. The system of claim 8, wherein at least one of the one or more rotor blades includes a wedge-like shape on a leading edge of an airfoil to reduce vortices at a blade tip.
12. The system of claim 8, wherein an asymmetric camber of the one or more rotor blades becomes more symmetric with respect to each blade's chord and distance away from a rotor hub until it is substantially symmetric near a blade tip, and wherein a length of the chord gradually increases with distance away from the rotor hub.
13. The system of claim 12, wherein the camber, the length of the chord, and an angle with respect to a plane of rotation of each rotor blade is adjustable, in a continuous or a discontinuous manner, to correspond to a fluid velocity at the nozzle outlet created by one or more ducts positioned within the convergent nozzle or an external annular ring, having airfoil characteristics, positioned about a circumference of a nozzle inlet or the nozzle outlet.
14. The system of claim 12, wherein the rotor hub includes an annular disc centered on a shaft driving the energy extraction device, the one or more rotor blades being adjustably coupled to the rotor hub in such a way to allow for modification of an attack angle of each rotor blade's airfoil.
15. The system of claim 8, wherein the one or more rotor blades are directly or indirectly coupled to a shaft driving the energy extraction device using a rope of inelastic material, the rope configured to redirect rotational forces on the one or more rotor blades.
16. The system of claim 8, further comprising an external annular ring, having airfoil characteristics, positioned about a circumference of a nozzle inlet or the nozzle outlet.
17. The system of claim 16, wherein the airfoil includes a greater circumference on a leading inlet edge than on a trailing outlet edge and is positioned from the nozzle outlet at a distance approximately equal to its camber.
18. The system of claim 1, wherein the convergent nozzle includes one or more apertures in a region near a nozzle outlet.
19. The system of claim 18, wherein the one or more apertures are selectively controllable such that, as the accelerated flow of fluid reaches or exceeds a preselected velocity, the apertures are opened to draw additional fluid flow into the accelerated fluid flow and modulate such accelerated flow to avoid excessive stress on the rotor.
20. A method, comprising:
- accelerating an ambient flow of fluid, including funneling the ambient flow of fluid into and through a convergent nozzle to a rotor of a turbine; and
- driving an energy extraction device, including one or both of an electric generator or a hydraulic pump.
21. The method of claim 20, further comprising transmitting power captured by driving the hydraulic pump to a hydraulic accumulator or a hydraulic motor attached to the electric generator.
22. The method of claim 21, further comprising capturing heat energy from the sun or waste heat from an exothermic process and transmitting the heat energy to the hydraulic accumulator using a heat transfer fluid and a heat exchanger.
23. The method of claim 22, further comprising transmitting energy from the hydraulic accumulator to a central system including one or more hydraulic motors attached to one or more electric generators.
24. The method of claim 20, wherein funneling the ambient flow of fluid into and through the convergent nozzle includes accelerating the ambient flow of fluid at a ratio between about 2.5:1 to about 7:1, inclusive.
25. The method of claim 20, further comprising positioning the convergent nozzle on a platform, including rigidly securing the convergent nozzle to the platform and mounting the platform to a tower such that the convergent nozzle and platform orientate a nozzle inlet with a direction of the ambient flow of fluid.
26. The method of claim 20, wherein accelerating the ambient flow of fluid includes accelerating an ambient flow of wind or an ambient flow of water.
27. The method of claim 20, further comprising coupling one or more rotor blades to a rotor hub centered on a drive shaft of the energy extraction device, including enabling rigging affixed to the rotor hub and between individual rotor blades to transmit angular forces on the rotor blades to the rotor hub.
28. The method of claim 27, wherein coupling the one or more rotor blades to the rotor hub includes coupling the rotor blades to the rotor hub in a range from (a) each blade being perpendicular to the hub at the point of connection to (b) each blade being displaced up to 0.10 radians from a tangential point at which the blade extends perpendicularly.
29. The method of claim 20, further comprising coupling one or more rotor blades to a rotor hub mounted on a releasable roller clutch, the roller clutch, when engaged, powering a drive shaft coupled to the energy extraction device.
Type: Application
Filed: Sep 28, 2011
Publication Date: Jun 7, 2012
Applicant: GaleMaster Power Systems, LLC (St. Paul, MN)
Inventor: Arthur Carlson (Saint Paul, MN)
Application Number: 13/247,765
International Classification: F01D 1/04 (20060101);