Patent Application
20110164985
None.
There are a number of devices taught in the prior art for using energy from the flow of a fluid to power mechanical machines. The simple water wheel used in grist mills to process grains is perhaps the most primitive. More recently, hydro-kinetic turbines manufactured by Hydro Green, Verdant Technologies, Open Hydro, and Free Flow Power used modified wind turbine designs in rivers and tidal flows. Each of these systems is expensive, heavy, and subject to problems in deployment and operation because of its composition, weight and size.
The present device was developed to overcome many of the problems associated with current hydro-kinetic technologies. The present turbine system is highly efficient, durable, light weight, manageable (using two-three person maintenance teams), cost effective, easy to manufacture, ship and assemble, environmentally friendly to aquatic life, and capable of generating power in low fluid flow. Thus, the present device meets many long-felt needs in the industry.
The present invention provides a new and useful device and method for the production of power. Prior art turbines have often failed or struggled to successfully produce power as a result of their size, metal composition (which is subject to corrosion), injury to the environment and wildlife, and high cost of production and maintenance. The demand for energy is rapidly increasing worldwide. Renewable and sustainable energy sources are also in demand. The present invention uses no fossil fuels, and thus generates no carbon emissions. In addition, other applications of the present device and method include production of hydrogen gas, electricity, aeration of oxygen depleted rivers, irrigation, pumping fluids, distillation of water, and the like.
A fluid driven turbine arrangement is herein described. The turbine comprises a cone with an array of curvilinear blades attached to the cone's exterior surface. The cone and blades are constructed of flexible, thermoplastic materials, though any other suitable materials, such as high density polyethylene polymers, carbon fiber, and the like, may be used. The cone is mounted to a shaft along the longitudinal axis. Power is transferred through this central shaft. In one embodiment of the invention, the central shaft includes a solid steel rod with a steel ring welded on each end for linking to the power generation system and to link to additional runner assemblies. Thus, water, air, or other fluid entering the runner is accelerated as it traverses the cone and blades, thereby increasing and harnessing the force with which the shaft is rotated, thereby increasing the production of torsional energy. Tests were conducted to determine power generation from a single runner, and the results of such tests are provided herein.
On aspect of the present turbine includes a cone and a plurality of curvilinear blades extending substantially along the length of the cone, from at or near the apex of the cone to at or near the base of the cone.
In another aspect of the present invention, each of the curvilinear blades includes two walls, a first wall oriented substantially upstream with respect to the direction of fluid flow and a second wall oriented substantially downstream with respect to the direction of fluid flow. The first and second walls come together to form the edges of the curvilinear blades.
In still another aspect of the present invention, each of the plurality of blades of the turbine is hollow.
In still another aspect of the present invention, the turbine also includes an adjustor for adjusting the pitch of the blades. The adjustor is preferably attached to the cone of the turbine as well as to one of the curvilinear blades.
In still another aspect of the invention, the adjustor is automatic and is adapted to change the pitch of the curvilinear blades in response to the rate of fluid flow.
In another aspect of the invention, the automatic adjustor includes a sensor for determining the rate of fluid flow, and an electronic data storage device for communicating the proper blade pitch based on the rate of fluid flow.
In another aspect of the invention, a turbine runner is provided. The turbine runner includes a shaft extending through a cone having openings at the apex and base of the cone, and a plurality of curvilinear blades extending substantially along the length of the cone, from at or near the apex of the cone to at or near the base of the cone.
In another aspect of the invention, the shaft has a first end that engages the cone and a second end that engages a device to be driven by the shaft.
In another aspect of the invention, the device to be driven by the shaft is an electrical generator, a hydraulic motor, or a pump.
In another aspect of the invention, the device to be driven by the shaft is a hydraulic motor that utilizes biodegradable hydraulic fluid that is not toxic to aquatic life.
In another aspect of the invention the turbine runner is located in a body of water while the device to be driven by the shaft is not in a body of water.
In another aspect of the invention, the shaft is in mechanical communication with a device to be driven by the shaft, but does not directly physically engage the device to be driven by the shaft.
Further features of the present invention will become apparent to those skilled in the art to which the present invention relates from reading the following description with reference to the accompanying drawings, in which:
a is side cross-sectional schematic of one embodiment of a turbine constructed in accordance with the principles of the present invention.
b is a photograph providing a front view of one embodiment of a turbine constructed in accordance with the principles of the present invention.
a is a schematic diagram of a plurality of turbines constructed in accordance with the principles of the present invention, the turbines in series. The diagram also depicts turbulence flow patterns around the devices.
b is a photograph depicting a plurality of turbines constructed in accordance with the principles of the present invention, the turbines in series. The photograph also illustrates fluid flow patterns along the blade of the turbine.
Theory of Operation
Fluid Flow
Flowing fluid is directed onto the blades of the turbine runner, creating a torsional force on the blades. This force acts over a distance and creates a rotational spin on the runner. In this way, kinetic energy from a moving fluid is transferred to the turbine creating rotational energy. In addition, fluid is accelerated as it moves along the cone and blade surfaces. The rotational motion, fluid acceleration, and blade conformation results in turbulence at the point of release as shown in
The runner described is a reaction turbine that is acted on by fluid, which changes pressure as it moves through the runner and gives up its energy. The runner is partially or completely submerged in the flowing fluid.
The power available in a fluid flow is represented by the following equation:
P=npghv
where:
In flowing fluid, the velocity head comprises a significant percentage of the head. However, in some fluid flows with significant drops in elevation there also can be a pressure head component. A significant component of the present device is its efficiency in extracting power from fluid flow. The device of the present invention is also efficient in low flow environments.
Turning the drawings, wherein like numerals represent like parts,
The present invention provides a fluid (water/effluent/air) driven turbine runner for converting the energy of a moving fluid. In one embodiment of the invention, the present device includes a cone containing flotation that supports an array of double-walled, helical blades that rotate on a central shaft (as shown, for example, in
In operation, fluid moves along the cone and blades and the cone accelerates the fluid. The helical blades convert the linear fluid movement into angular momentum, thus driving the runner to rotate. As the accelerated fluid discharges at the end of the turbine runner, turbulence develops creating a vortex when the accelerated fluid and the slower ambient fluid intersect (see, for example,
The cone and helical blades may be manufactured from any suitable material, including, but not limited to, flexible, high density polyethylene (HDPE) polymer, thermoplastic materials, carbon fiber, and the like. The blade is preferably double walled. The front surface is designed for efficient capture of energy from the flowing fluid. The back wall is designed for two purposes: first, to provide support for the front wall, and second, to manage fluid flow to create an ideal turbulence for optimizing performance of additional runners in the series. This management of turbulence is unique and important in the performance and efficiency of the present invention. In addition, blade pitch can be adjusted from the ‘pitch adjustment’ assembly such as that shown in
An example of a high torque system can be found when power is required to drive a large capacity pump at low rpms. Hundreds of gallons of water are being powered through the system at low rpms. A system requiring higher rpms involves the power required to drive an electric alternator for use to power batteries on a boat or platform. The alternator requires approximately 400 rpms but does not have high torque requirements.
The conversion of energy from a stream of fluid into mechanical energy is a primary goal of the present invention. Preliminary experiments showed that the design of the present device results in unexpected amounts of torque. To test this claim, experiments were designed and conducted to study the performance of the present conical turbine at different flow rates.
A cone and four blades were constructed from 1.22 m×2.44 m sheets of HDPE with a thickness of 3.2 mm. The cone was shaped with a length of 1.22 m and a base diameter of 0.71 m tapering to a 5 cm diameter. Blades were attached resulting in a total base runner diameter of 2.6 m. The blades were double walled and fastened to the cone body with rivets and then fused by welding. A 2.5 cm diameter HDPE plex water tube was cut and fitted to the edge of each blade, fastened with screws and then welded.
A 1.8 m long and 5 cm diameter solid steel shaft was positioned axially through the cone. To each end of the shaft was attached a connector ring formed from 1.6 cm diameter steel rod. Two solid steel rods 1.9 cm diameter and 2.6 m long were positioned in the base area, welded to the axial 5 cm shaft, and attached to the cone's surface and also to the base end of the blades. These shafts allowed adjustment of the blades.
A 12.5 cm diameter tubular drive shaft was attached to the runner connector ring using a steel clevis pin. The clevis pin allowed rotation of the connected parts about the axis of the pin. The pin was a solid steel rod with threads at the end. To fasten the clevis to the runner shaft, the pin was positioned through the clevis hole and runner connector ring, and then screwed into the clevis shank. This allowed for easy assembly and disassembly of the runner from the drive shaft. At times, the turbine runner generated in excess of 5,600 ft lbs of torque. Numerous times during testing bolts and shafts were unexpectedly sheared and twisted due to this significant and unexpected torque.
The runner drive shaft was connected to a power take off (PTO) male adapter welded to a 5.1 cm steel shaft. The shaft was connected to a platform constructed from a fiberglass V-hulled boat reinforced with structural, 5 cm tubular steel housing (
A gear box manufactured by Rexnord/Falk Industries (Model MRK2060F—3A), was positioned within the housing. (Rexnord, 4701 W. Greenfield Avenue, Milwaukee, Wis. 53214-5310). The gearbox had a ratio of 1:85.69 rpms. It served to accelerate the runner's rotational movement from a range of 4-7 rpm to 342-600 rpms respectively. The torque required to overcome the inertia of this system, from the PTO through the generator, was approximately 170 ft-lbs. Torque was measured using a hand-held Proto torque wrench with a 0.61 m extension and attached adapter to link to the male PTO fitting on the stern of the platform boat.
A 12 kw Voltmaster power take off (PTO) generator manufactured by Wanco Inc., model PTO 15/12 was installed. (Wanco/Voltmaster 5870 Tennyson Street, Arvada, Colo. 80003). Discussion with company engineers revealed that a minimum of five horsepower was required before the generator would produce any electricity.
Torque was calculated using the following formula HP=(Torque×RPM)/5252. 5252 is a constant. Thus, minimum torque required to produce five horsepower is dependent on the RPM of the driving force (runner). One BP=746 watts. Five RP=3,729 watts. In theory, the present system, operating at four rpm, produces the following torque:
Torque=((5252×HP)/RPM)/746 watts
Torque=((5252×3,729 watts)/4 RPM)/746 watts
Torque=6563 ft. lbs. at 4 RPM
Torque=3751 ft. lbs. at 7 RPM
Deployment consisted of first launching the platform, connecting the drive shaft to the runner, then either positioning the assembly in a river current or moving the platform through a lake using a motorized boat or boats. Once the flow rate reached 0.75 m/s the runner began rotating. At 1.3 m/s the turbine activated the generator and produced approximately 125 volts of electricity.
To determine power, a load was placed on the generating system using a forty amp maximum capacity electric stove with four burners and one oven. To measure electrical characteristics, a Uni-T model 233 power meter with digital readout and USB computer connection was used. This meter was connected to a Dell laptop computer and the data was stored in Microsoft Excel format for later analysis. The stove was connected to a 220V electrical source. Each burner and oven element was tested to determine resistance and amount of current/power used at maximum capacity. (Table 1).
The stove was attached to the generator system using the 220 V, 40 Amp plug. A data logger system was connected to monitor water flow before the runner and rpms of the runner drive shaft. (MultiLogPro, Fourier Systems Inc. 9611 W. 165th St. Suite 11b, Orland Park, Ill. 60467). To measure rpm, a Photo Gate DT137 sensor was mounted to the steel housing and detected a steel rod connected to the runner drive shaft each time it passed through the infrared beam. Water flow before the runner was measured using a Flow Rate sensor DT254. The sensor was mounted on a rod and positioned aft on the platform at approximately 0.6 m below the surface. The runner was position approximately 2.5 meters behind the platform. Both the Photo Gate and Flow Rate sensors were connected using mini Din plugs to the data logger, which was directly connected to a Toshiba laptop computer running a Fourier software data analysis program, MultiLab. Data were collected and stored in Microsoft Excel format for analysis.
To propel the turbine system in a lake, a 160 hp, 9.1 m long pontoon boat and a 50 hp, 4.6 no long, semi-V bottom boat were used to tow the turbine system. At wide-open-throttle (WOT) on both boats, the average water flow and runner RPM achieved under load was 2.09 m/s and 4.33 RPM respectively.
The 2.6 m diameter runner in 1.6 m/s water flow produced an average torque of (665+6,105)=6,770 ft-lbs. in the first experiment, and (691+6105)=6796 ft.-lbs. of torque in the second experiment (Table 3), at WOT using a combined 210 hp of engine power.
The experiments detailed above were conducted in the safe environment of a lake, as opposed to the more dangerous environment of a river.
In view of the above, an embodiment of the present invention having a single turbine runner produces enough torque and RPMs to conservatively operate an 80 kW system in an average river flow rate of 1.6 m/s. Disregarding the minimum generator operational torque and relying only on the torque produced in the example above, (average=664 ft lbs, or 900 N.m.), the maximum alternator size would be the Alxion 500 STK6M (450) or 39.5 kW (52 HP) of power in 1.6 m/s flow rate. Adding in the minimum torque required to overcome inertia, 170 ft. lbs., plus the average 664 ft. lbs., the present device conservatively achieves 834 ft-lbs. or approximately 1130 N.m., enough torque to power a 43 kW unit (57 HP). It is contemplated that these numbers may vary depending on specific embodiments of the present invention, as well as the conditions under which the device(s) are employed.
It is contemplated that various modifications to the present device will be apparent to those of skill in the art upon reading this disclosure. Various embodiments and modifications to the present device are now described, with the understanding that the present device is not limited by such description.
One embodiment of the present device includes a thermoplastic material edge cap constructed from plex tubing or other suitable materials. This cap shields the rough edges of the runner blades, providing protection for fish and other wildlife. The cap also reduces the potential for catching and accumulating debris. The function of the edge cap may also be achieved as an integral part in a molding design.
Another embodiment of the present turbine has variable blade pitch. Adjustable rods extend across the posterior area of the cone, through the polymer skin and through the blades. Adjustable fasteners provide a method of adjusting the curvature or pitch of the blades. Thus, blade conformation can be adjusted to optimize performance in areas of flow that may differ. For example, one flow may average 2 m/s while another flow averages 4 m/s. Thus, one unit can accommodate many different flow rates by simple blade adjustments.
Another embodiment of the present turbine has a double walled blade. This double wall is adjustable using the adjustable rods. Furthermore, the back wall is designed to form pyramid shapes and other geometric forms to provide support for the front blade. In addition, these shapes are specifically designed to manage turbulence by optimizing flow direction and flow force to enhance the performance of subsequent runners in the series and among series. As turbulence is managed during the water discharge process in a parallel series of runners, the turbulence from the left series and right series bifurcate at a distance behind the runners. A third series of runners, positioned between the left and right series is positioned at the region of bifurcation to enhance performance.
Still another embodiment of the present device includes a cone with no blades positioned in front of the runners. This cone functions to assist in debris deflection as well as control of turbine rotation that can act as a braking system in periods of high water flow.
Another embodiment of the present turbine is able to avoid debris in flowing water. Runners are designed to tolerate varying degrees of debris in rivers. First, the curved blade system facilitates movement of debris through the runner. Secondly, the high torque and low rpm can simply ‘push’ larger debris such as trees and ice flow to the side and away from the runner. As the runner flings away debris, its operational pathway is kept clear. Multiple runner blades are aligned to provide synchronous movement of debris away from the system. Furthermore, in a parallel runner series, each series turns counter to the other to provide stability. From a front view, the left series turns counter-clockwise and the right series turns clockwise. Thus, debris entering the middle of the series will be lifted up and out of the array.
Another embodiment of the present turbine is the runner and blades are constructed from thermoplastic materials and are very tolerant of impact and easily repaired or replaced in the event of damage. As opposed to stationary, metal units, the present runners have some degree of flexibility with pliable parts.
Another embodiment of the present turbine is lightweight and durable, resulting in a system that can be managed by a team of 2-3 people for the larger turbines and 1 person for the smaller units. No special heavy lifting equipment is required and the system can be readily transported, assembled, and installed in remote places.
Another aspect of some embodiments of the present device is that they are very easy to maintain and repair. Because the runners in these embodiments are made from thermoplastic or other polymer materials, a technician with little experience can weld any broken or cracked polymer parts with one simple tool and pieces of the polymer. These tools can be included in a basic kit.
Another embodiment of the present device is operable to work on a river surface, tethered to the river bottom by a cable/anchor array. This system can be easily maintained and is portable.
Another embodiment of the present device is operable to work from a boat or floating platform. This system can be used to produce electricity, charge batteries, operate electric motors, pump water, clarify water, and purify water for drinking. This system can be deployed from the side or aft of the anchored platform. This system is lightweight and can be deployed by one or two persons.
Another embodiment of the present device can be submerged and tethered to a river bottom. This embodiment preferably employs flotation tanks mounted to a steel frame work. When repairs are needed, air is pumped into the submerged tanks to surface the unit. Thus, no repairs need to be performed beneath the water surface.
Another embodiment of the present invention employs a submergible, hydraulic motor attached to the runner drive shaft. The hydraulic motor utilizes a biodegradable fluid that causes no harm to aquatic life forms. The runner's rotational force powers the hydraulic motor resulting in a flow of pressurized hydraulic fluid to an onshore accumulator. One or more runner systems can contribute to the hydraulic system. Pressurized fluid in the accumulator tank powers a hydraulic motor/gearbox/generator assembly. The advantage to this system is that no electrical components or wires are submerged and it is much easier to maintain the drive train and generator system.
It is also contemplated that the present device can be expanded by adding more runners fore or aft of the power unit to produce greater amounts of power.
Another embodiment of the present turbine system is constructed of HDPE polymers, or other suitable material, and is resistant to the impact of cavitation caused by vapor bubbles attached to surfaces. Other hydro-kinetic systems using metal blades find cavitation to be problematic, resulting in early deterioration of metal components and costly repairs and maintenance.
Another aspect of the present turbine system is that it is fish friendly because of the helical confirmation of the present cone and blades, rather than sharp, protruding metal blades that other systems employ. Helical screws are often used to transport spawning fish over dams in rivers and streams. In addition, helical screw pumps permit live fish to be moved in water via pipe systems over large horizontal and vertical distances without damage. Further, the rotational speed of the present device averages between 4 and 8 rpms, making it possible for fish to maneuver around or through the system. Also, in some embodiments of the invention no electrical wires or generators are located in the water to cause electrical shock to fish and aquatic life.
In another embodiment, the present device can be manufactured in segmented parts which simply ‘snap’ together. Thus the runner can be easily shipped, disassembled and later reassembled on site. Repairs can be made by exchanging runner parts.
Another aspect of the present invention is that the runners can be manufactured on or near the site of application. Thus, bulky runner assemblies do not have to be shipped. Only the raw HDPE sheet material, or other materials, can be shipped.
Another embodiment of the present turbine can be molded in one piece adding greater strength and decrease manufacturing costs. Further, the turbine may link multiple runners on a single shaft.
Another aspect of the present turbine is the ability to pump water. An exemplary pump 7 suitable for use with the present invention has been developed by WindTrans systems LTD, Seaforth, Ontario, Canada. The unit pumps 700 liters of water per revolution and operates between 5-18 rpms. At 7 rpm the present turbine system could pump approximately 5 acre feet of water per day at 1265 gallons per minute.
Another embodiment of the present turbine can be deployed in warmer regions along rivers that require high energy demands for air conditioning. Then, these same units can be transported via river to colder climates to provide energy for heating homes in winter.
Various embodiments of the present turbine can be used as wind generators. Furthermore, testing shows that the turbines can be used both in water and air to power the same system. Additional testing has shown that the runner positioning is best offset to the direction of flow in both air and water to maximize efficiency. Preliminary results show a 22 degree offset to be most efficient.
Another embodiment of the present turbine system can be used to provide energy for hydrogen gas production.
Another embodiment of the present turbine can be used to provide aeration to rivers. This can be provided by a number of design choices relating to the present invention. First, the runner blades can be modified by adding small holes in the surface. The blades are only partially submerged, thus as the blades rotate air is captured in the small holes and released into the water. Secondly, a modified blade design results in rotational speeds >60 rpm, thus water is “splashed” into the air. Finally, a pumping system can be used to spray water from the river surface into the air.
Another embodiment of the present turbine can be used to incorporate and/or clarify discharged waste from industrial or municipal sources into river water.
Another embodiment of the present turbine and pump system can be used to pump fluids in pipelines that cross rivers. The pump system can be connected directly into the submerged pipe systems.
Other features of the blades associated with the present invention include: low revolutions per minute (rpm), attachment of mini-blades to improve performance, a HDPE polymer (or other suitable material) edge cap to protect fish and improve debris handling, and helical conformation to further protect fish and other aquatic life. Because the runner rotates between 4 and 8 rpms it is very fish friendly. In addition, the helical shape of the blades expels fish in a safe manner. Mini-blades have been designed and implemented to enhance performance to accommodate a variety of fluid flow conditions.
The runner may contain buoyancy means mounted within the cone. In other embodiments, buoyancy may be provided by closed cell foam.
The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
This application claims priority of U.S. Provisional Patent Application No. 61/285,160, entitled “Conical Fluid Turbine Runner,” filed Dec. 9, 2009, and which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61285160 | Dec 2009 | US |
