Patent Application
20120175882
1. Field of Invention
The invention relates to an improved natural wind energy accelerating ducted focusing and control system of both push airflow acceleration and pull vacuum funnels-diffusers, having a number of large area, low cost reconfigurable hard shell fiberglass, carbon fiber and or sail fabric PVC coated vinyl fabric or membrane funnels, with panels which can be expanded or retracted. The ambient wind facing funnel duct mouth captures ambient wind accelerates it into a mechanical wind turbine. Additional rear facing diffuser with diverging duct funnels and diffuser rings to control boundary layer airflows, creates an additional strong rotating vacuum behind the turbine blades and further accelerates the wind through the turbine blades without causing the airflow to stall or break away.
The wind turbine consists of a machine housing located on a frame so as to rotate about its axis and receiving a generator, and a brake, and a wind powered rotor mounted in the machine housing having at least two rotor blades designed to survive and produce mechanical-electrical energy in the most hostile wind environments.
Wind energy is often used to generate electrical power using the rotation of large slow turning wind turbines to drive electrical generators. A group of generators are often referred to as wind farms. The density of wind energy, in terms of watts per square meter, is one of the highest among other forms of natural energy. This invention accelerates ambient wind speed by approximately 200-300% and converts the accelerated wind energy into electrical energy at a much lower capital and operating cost per Megawatt than current state of the art wind generators.
Using fossil fuels—coal, oil and natural gas—to make electricity dirties the world's air, consumes and pollutes water, hurts plants and animal life and creates toxic wastes.
Wind Generators are increasingly used for power generation; typically through the use of a tower-mounted 2-3 bladed turbine, which typically rotates slowly at 15-25 RPM, which rotates an electrical power generator to produce electricity.
While wind itself is a clean, inexhaustible, indigenous and abundant “free” energy resource, conventional wind generator turbines built to capture wind energy typically sit on a very tall heavy steel mast or support tower, carrying on top a very heavy weight of turbine, gearbox and generator and the very long propeller blades use fragile cantilevered beams. Because most suitable locations ambient wind speeds are slow at around 20 mph average annual wind speed, with a typical 500-600 watts per square meter of wind power density, their propeller blades are necessarily built at huge sizes, with blades often around 150-200 feet or more long, in order to produce between 1 to 5 Megawatts of power. Their size and weight makes them quite fragile, the mechanical stresses allowing for only a slow rotational speed. Many models add a large heavy gearbox to increase the slow turbine shaft speed to drive a conventional high-speed electrical generator. The turbines must be turned off in high wind speed events of 50mph or more. It is not uncommon for the entire structure to be blow over in storm weather resulting in large capital losses. At least 3 turbines have blown over in the US alone in the 3 months period of November 2009 to January 2010.
Traditional commercial scale wind generators blades are long, and require special expensive infrastructure to manufacture and transport. With a typical 100 ft blade weighing around 4.5 tons and a 177 ft blade weighing around 13 tons the weight of the blade is not proportional to the size and power rating of the machine. Each extra meter of length requires extra mechanical strength which adds further to the structure's weight and so compounds the mechanical bending and G-force problems. Additionally the bending moments across the swept area of the blade can vary considerably with a difference of several meters a second in wind speeds between the top and the bottom of the blades rotation. This all adds up to a substantial increase in fatigue, not only in the blade structure but the machines hub, bearing, drive shaft and support tower.
Traditional wind generators only extract between 25%-30% of the wind energy in the blades swept area out of a theoretical 59% maximum, as a large percentage of the ambient airflow within the propeller's swept area passes by a small number of blades without impacting the blades.
Conventional wind turbines cannot operate at wind speeds above about 50-60 mph because the long fragile blades will disintegrate.
Because of the very high capital costs, a megawatt of conventional wind generator created electricity has net cash-financing-generating costs about 2 or 4 times as much to produce as a megawatt of natural gas, coal or oil-generated electricity. Thus without government subsidies, current state of the art wind generators cannot commercially compete against gas, coal and oil. This invention changes the economics in favor of wind power by generating much more renewable energy wind powered electricity for a significantly lower capital investment.
2: Advantages of my Invention over Prior Art
Utilizing a collection of both higher cost carbon fiber, Fiberglass and-or metals as well as inexpensive materials such as, sailcloth, PVC coated vinyl fabric, or other fabric membrane panels, sailboat technology roller furling devices, airflow speed control devices and methods easily implemented to form a more powerful, cheaper wind accelerating push-pull funnels-duct diffuser assembly. The first wind-facing structure is a gentle cone angle push-funnel or duct for accelerating ambient wind speed to approximately 1.5 to 3 times ambient wind speed thereby increasing air power density by approximately 400% or more facing into the prevailing wind on the upwind side of a hard-shell shrouded turbine. The second is a diffuser-augmented pull or vacuum funnel assembly of two or more funnels and diffuser-injector rings on the downwind side of the hard shell shrouded turbine which creates a smooth airflow venturi vacuum to further accelerate the wind through the turbine to approximately 200% to 300% ambient prevailing wind speed, thus increasing power density to between 10 to 20 times ambient wind power. This is much greater wind power density increase than any state of the art accelerating wind generators
The turbine can generate significantly more power over a wider range of ambient wind speeds than prior art turbines including push only or pull only diffuser augmented turbines such as disclosed in U.S. Pat. No. 7,218,011 B2.
The funnel size to cone angle ratios and circumferential diffuser-injector rings are placed and designed so as to accelerate the ambient wind speed without causing the airflow in and around the funnel assembly to separate, collapse or break away.
The structure also contains mechanically opened and closed wind control doors and retractable panels for controlling gusts and managing the faster more powerful airflow into a wind powered electricity generating turbine. The entire structure is constructed at a net per-Megawatt cost significantly lower than current state of the art non accelerated ambient wind generators and vacuum-only wind generators.
Some embodiments include fiberglass or other hard venturi membrane material or large deployable-furling sailcloth or PVC coated vinyl fabric panels accelerating the ambient airflow, by both push airflow acceleration and pull vacuum funnels. Opening and closing funnel wall doors and panels to control the speed and amount of airflow into the turbine blades, doors to focus airflow in preferred directions and to restrict or close off turbine airflow when desired, wind speed and direction sensors and control programming and/or circuitry that tracks trends in wind direction and speed, and anticipates the need to move the facing direction of the wind-accelerating funnel to direct changing ambient wind into the funnel, and to provide at least 10 to 20 times net wind power density increases to the wind-powered turbine. Also make wind power at an ambient wind speed that is lower than could normally operate the turbine without the Improved Injector Venturi Accelerated, Wind Turbine.
What it Accomplishes
For air density of 1.225 kg/m3, corresponding to dry air at standard atmospheric pressure at sea level at 15° C. The formula for the power per m2 in watts=0.5×1.225×v3, where v is the wind speed in m/s. (Note: MPH*0.45=m/s, MPH*0.8684=knots)
Details of the Invention.
Improved Injector Venturi Accelerated, Wind Turbine
A new push-pull injector venturi airflow accelerator with both a front-mounted push funnel and a rear-mounted pull-vacuum funnel with one or typically two or more rear diffuser air bleed-in injector rings, which are strategically located further back than is customary on a larger rear vacuum creating funnel creates very large airflow increases inside the venturi throat without creating eddies or breaking away or stalling the inside and outside airflows. This greatly accelerated airflow drives a hard-shell shrouded high-speed wind turbine and electrical generator to produce much greater electrical power per unit of capital than conventional wind turbines.
The funnels are made with a typical cone angle from the centerline of between 10 degrees to 16 degrees. Small variations beyond these funnel cone angles may also produce similar results.
Various airflow-directing fins, slots or slats can be placed at strategic locations to further direct and smooth ambient airflows in and around the funnel assembly to eliminate or reduce airflow separation, stalls or breakaways.
The push-pull venturi invention design also produces significantly more power than state of the art, pull-only vacuum funnel generators with diffusers and mixing slot such as described in US Patent Number 2009/0230691 A1.
As described in Provisional Patent Number EH 993286360-US which was filed on Jan. 19, 2010 and testing by the Applicants, resulted in increased wind speed of 200% or more. This Venturi Injector push-pull design improvement results in wind speed increases of 200% to 300% or more, thus significantly increasing available ambient wind kinetic energy to drive turbines.
Instead of bringing the turbine up to the higher ambient speed wind area on heavy, high steel masts as conventional wind turbines do, the Improved Injector Venturi Accelerated, Wind Turbine invention is designed to use a lower-height steel, aluminum or other material tube or frame to support fiberglass, carbon fiber and deployable-furling sailcloth, PVC, or similar low cost membrane venturi injector panels to scoop up, capture by both push and pull control and accelerate higher-speed airflows into a more soundly engineered, smaller diameter higher speed multi-bladed turbine which is located much more conveniently closer to the ground, where it can be supported and maintained more easily and cheaply. The wind accelerating device is designed to survive the highest wind events without being prohibitively expensive.
The venturi injector push-pull accelerated airflow is also more actively gust controlled into a large adjustable hard paneled or flexible membrane venturi to ensure the maximum energy is captured from any given ambient wind without overstressing the turbine.
This invention uses low-cost and much larger turbine to venturi funnel ratios, fiberglass or hard shell shroud, deployable-retractable sailcloth, PVC or other membrane outer funnel panels to create larger, sturdier, more efficient controlled push-pull venturi injector to accelerated ambient airflow to approximately 2 to 3 times the ambient wind speed, to rotate a state of the art multi-blade air turbine designed to capture 40-50% or more of the net kinetic energy in the controlled accelerated airflow.
As a front push wind funnel section of the venturi narrows, the ambient air flows more quickly. But if the funnel is made with incorrect proportions it will either not capture sufficient wind energy, or it can create eddies which collapse the smooth airflow, thus robbing power. It can also be too large and cumbersome, thus wasting material.
This invention uses more theoretically sound gentle angled accelerating funnel shapes consisting of;
If steeper cone angles are used on the funnels one or more small injector rings or fixed “slots or slats” surrounding the outer lip is used may redirect ambient airflow around the outside and inside of the venturi funnels to avoid air stalls or breakaways.
One or two or more injector-mixer-diffuser openings and outward-angled accelerator panels around the all or most of the circumference of the rear venturi funnel placed further back than prior art diffusers are sited approximately between one third to three quarters of the funnel assembly length. This allows a small portion of outside ambient air to be accelerated then injected into the rearward flowing accelerated vacuum airstream to stop or reduce airflow stalls, airflow collapses or breakaways inside the funnel, thus allowing a larger more powerful vacuum rear venturi funnel assembly to be deployed. The larger rear venturi funnel injector assembly significantly increases net inside venturi airflow acceleration. Conventional turbine diffuser rear funnels place the openings immediately adjacent to the turbine blades thus reducing potential efficiency.
Steeper funnel cone angles than shown in the drawings can also be utilized provided appropriate airflow controlling smoothing devices such as leading edge slots or slats on the front push venturi funnel outer intake and either larger diffuser injector inlets on the rear venturi funnels or two or more smaller opening diffuser rings or partial rings instead of one. All funnel shapes must ensure the smooth flow of air in and around the structure to avoid airflow breakdowns or airflow stalled areas.
Resulting variable electrical power output can now be controlled and smoothed to match grid requirements using state of the art electrical power control devices provided by third parties and now widely available.
The restrictive description and drawing of the specific examples do not point out what an infringement of this patent would be but are to enable the reader to make and use the invention.
Drawings Figures Included.
Components of the Invention and How They Interact.
Additional Details of the Components of the Invention
The Improved Injector Venturi Accelerated, Wind Turbine with controlled wind funnel push-pull accelerators has one or more of the following components;
Supporting Structure Typically Made of Carbon-Fiber, Steel or Aluminum Pipe or Trusses.
This structure supports;
The Funnel may have Various Passive Airflow Control Devices, either-or;
The Funnel Accelerator May Have Active Airflow Control Devices.
Typical Accelerated Controlled Airflow Wind Power Turbine Components
A) For land based units; Heavy foundations made of concrete and base structures typically made from steel or aluminum to support the venturi air funnel structure, airflow controls and turbine and electrical generators. As well as ballast to anchor the entire structure in a high wind location and counteract the large wind forces. This structure may include a swivel plate and wheels or rails to allow the entire wind accelerator generator structure to rotate to face the different ambient wind directions common in a particular location. For offshore units any suitable platform may be utilized to support the turbine-funnels assembly such as a lighter weight pylons or for deeper waters a semi-submersible platform.
B) Sturdy tube or truss support frames to support the hard-shell, or flexible membrane funnels-venturi accelerator components, able to withstand very highest winds recorded in the location the turbine is situated. The support frame is typically made from welded tube or lattice steel pipe or aluminum. The venturi injector funnel will typically be round in cross section.
C) Either hard-shell such as fiberglass or carbon fiber, and-or fabric or other membrane sails and panels attached to the frame either temporarily or permanently. If utilizing fabric panels they will be supported using similar components to sailboat roller furling sail technology. With powered furling-unfurling devices to deploy the fabric panels fully during lower winds and progressively reduce and control the wind concentrating effect forces during wind gusts and during longer term high wind events.
D) Computer controlled servos and motors to repeatedly progressively open and close venturi doors and panels to manage low and high wind flows into the turbine. The computer responds to a number of sensors located in the ambient air stream, the funnel and turbine to fully deploy the funnel panels to create the maximum wind energy recovery from any given lower speed airflow and to furl or progressively close the funnel panels during high wind gusts and storms.
E) Wind turbine to capture the mechanical energy of the accelerated airstreams and turn the energy into shaft power to turn an electricity generator. The mechanical load of the generator is controlled by a feedback control to maintain a relatively constant rotational frequency of the shaft of the generator.
F) Pitch regulated wind power turbine machines featuring an active control system, which senses blade position, measures output power and instructs appropriate changes of blade pitch.
G) Turbine over-speed control is exerted in three main ways: various venturi wind-control doors opening and closing, aerodynamic stalling or blade furling, and mechanical braking.
H) Conventional current state of the art electrical generators, controllers and electrical distribution systems to create and distribute electricity generated by the wind turbine.
All venturi funnels components with cone angles typically between 10 to 15 degrees or greater from the centerline. Rounded corners are used to smooth air flow.
Alternative Ways of Doing It.
This invention achieves a very significant increase of power output of a wind generator per unit of capital employed by focusing, accelerating and controlling natural ambient airflows using both push and pull funnel-diffusers to accelerate wind speed by 200% to 300% or more utilizing a collection of inexpensive materials such as steel, fiberglass, carbon fiber, sailcloth, PVC coated vinyl fabric, or other hard or fabric membrane panels, which can include conventional hinged hard venturi panels and-or sailboat technology roller furling devices, airflow control devices and methods easily implemented to form a more powerful, cheaper wind accelerating push-pull funnels-duct diffuser assembly
The venturi accelerator device has strategically placed diffuser rings or injectors, deployable-retractable funnel panels made from practical, available inexpensive hard shell fiberglass or other hard material or flexible membrane-unfurling and furling control technology, using off the shelf roller furling systems, and powered or wind opening wind control doors and panels, while also providing for better controlling high airflow events. The wind power generating device of the present invention is very flexible in design to capture more ambient low and high speed ambient wind energy and provide higher levels of power generation capacity from any given ambient airflow in a sturdy, survivable structure.
This generator can during high wind events provide excess electrical power than contracted to feed the electrical grid. This excess power could be directed to power a pumped hydro electricity storage scheme, a nearby water desalinator to make fresh water or to power an electrolyzer used to generate hydrogen from water.
P. Sterling; Application Number AO Provisional Patent EH 993286360-US, which was filed on Jan. 19, 2010
P. Sterling Application Number AO Provisional Patent Number EH 993289701-US, which was filed on Sep. 9, 2009
Application Ser. No. 12/236,249 Publication number :US 2009/0230691 A1 Filing date: Sep. 23, 2008. Walter M. Presz, J R., Michael J. Werle
U.S. Pat. No. 6,756,696 Yuji Ohya et al Jun. 29, 2004
U.S. Pat. No. 6,981,839. Leon Fan Jan. 3, 2006. Wind Power Generator.
U.S. Pat. No. 7,368,828 B1 Calhoon. May 6, 2008 Wind energy System.
U.S. Pat. No. 6,984,899 B1. Pahl W. Rice. Jan. 10, 2006. Wind Dam electric generator and method
U.S. Pat. No. 5,982,046. Vu Xuan Minh. Nov. 9, 1999 Wind power plant with an integrated acceleration system.
U.S. Pat. No. 4,288,200. Louis R. O'Hare. Sep. 8, 1981 Wind Tower Turbine.
U.S. Pat. No. 6,749,393. Yevgeniya Sosonkina. Jun. 15, 2004 . Wind power plant.
U.S. Pat. No. 6,981,839. Leon Fan. Jan. 3, 2006. Wind powered turbine in a tunnel.
U.S. Pat. No. 7,189,050. Sellman. Mar. 13, 2007. Cross-flow wind turbine.
U.S. Ser. No. 12/283,776. Al Kuljack. Sep. 16, 2008 Wind Catcher and accelerator for generating electricity.
U.S. Pat. No. 7,218,011 Clement Hiel et al. Issue date: May 15, 2007
U.S. Pat. No. 4,422,820. Jerome Kirsch, Edward Markow Issue date: Dec. 27, 1983
U.S. Pat. No. 4,075,500 Richard A. Oman, Kenneth M. Foreman Issue date: Feb. 21, 1978
U.S. Pat. No. 4,482,290 Issue date: Nov. 13, 1984. Kenneth M. Foreman, Barry L. Gilbert
Application Ser. No. 10/495,502 Filing date: Nov. 19, 2002
U.S. Pat. No. 4,132,499 Issue date: Jan. 2, 1979. Jan. 2, 1979. Ozer Igra
