GB2137285A - Vortex turbine - Google Patents

Abstract

The turbine is operable by wind or water and comprises a spiral casing arranged to set up a vortex flow in a bladed rotor contained in the casing, the flow exhausting from one end of the rotor in an axial direction. <IMAGE>

Description

SPECIFICATION The vortex velocity turbine Preamble For quite some time, gaining rotational power from the Wind has remained in the doldrums, being mostly nurtured by a heroic band of very dedicated people with little finance, but high skills, fueled by a devoted dedication to the Cause for a fruitful Harnessing of the Wind, mostly as yet, untapped.

Several quite sound Er aged inventions have been redeveloped-by enthusiasts, together with their variations or close cousins. Most of these, when in their smaller sizes, are doing a very good job, yet as greater 'Unit Powers' are built, quite serious and expensive difficulties become annoyingly evident.

It is suspected that through adhering to the well proven traditional "Windmill" method, any further real progaaess of of Harnessing the Wind to serve he heavy Power Demands of today, will advance and stumble in much the same way as the development of the much loved and used "Water-wheel". They became too big and unwhieldy, tied by their basic design of buckets about the outside of a spoked wheel.

It is rather similar with the current favourites now being developed with great dedication, backed with the most modern fruits of aero-dynamics.

Reference here is to the Propeller; (Windmill Method); the Darrieus Vertical Rotors, and the various "H" Rotors. Consequently, it is thought that not only is a new machine required as a stepping stone into a new Wind Power Future, but also, a brave new attitude to the subject, rather as the Hydro-electric engineers faced in the 20's. On several occasions during the development of the Velocity Turbine, a 'clinging' return to the principles of the Propeller was of some comfort, yet proved quite diversionary.

Therefore, some patience and time is sought from the reader, so as to establish a full realisation of the Machine's full potential.

The Machine is expected to bring forward Wind Power from the "Windmill Age" rather like the three Water Turbines did to the Waterwheel, half a Century ago.

Essence of Principle The Character of the machine is a:-"Prime Mover". It provides primary rotational power from the Wind, or from Water. The Turbine provides this power through the effects of a Linear, Inward/Central Outward Vortex Flow of Air of Water.

The Turbine is designed to accept and gain power from the Velocity of the Wind (Air Speed), and when fully immersed in water, power from flowing water not under static pressure. (Velocity Head).

The Turbine is able to drive most normal rotating machines including Dynamos and Alternators, pumps and compressors etc.

The Turbine, its full name being a "VOR TEX VELOCITY TURBINE" (VVT), can be categorised as a Medium to High Specific Speed type of machine, with the Specific Speed not necessarily being set and dependant on the choice of Blade, but more to the proportional size of machine/vortex whirl ratio.

The Turbine has been expressly designed for Long Term 24 hour Heavy Duty Service to gain power from any strength of Wind, with its efficiency, strength and Fitness for the job, increasing with size. The main design characteristics are of Simplicity, Robust Strength, and Adaptability of its site installation.

The Turbine consists in its basic form, only one moving part, the Rotor, named the "Vortexor", running within a Spiral Casing like a Fig. 6, which hold two frames at each end containing ideally, Taper Roller Sealed Bearings.

In working out the power of most common wind turbines, the total Swept Area is considered. With the VVT, the total Exposed Area is to be considered.

The Turbine is not uni-directional in Character as are some Vertical Turbines, and requires to be turned face into the Wind, + 8 . Other than this requirement, the turbine shaft can be vertical, horizontal or on any angle.

The Turbine has a Self-governing overspeed Character, where the free Runaway Speed settles down to a maximum speed no matter what the Wind force, thereby affording its essentials storm-proof resistance.

Step by Step.

(Wind Version) Fig. 1 shows a general view of the Vortex Velocity Turbine. Referring to the drawing, with the machine at the presented attitude, the observer would be viewing it face into the wind, slightly behind and to the right of it; i.e.

the Vacuum 'V' side. This view shows the general make up of the "6" shaped Main Side Frame, the Vortexor, (rotor), one of the three blades and the structure supporting the Main Turbine Casing.

Refering to Fig. 1, therefore, the explanation continues as follows: With the Turbine aligned square into an Ambient Wind, a Rectangular Section of Wind is offered to and through by means of a Venturi Style Opening formed by the Aerodynamically shaped Leading Edge 1, and the top curve of the Vortexor Housing.

The Leading Edge 1 is held firmly, without whip by 'adequate' firm anchoring to the Antifatigue Plates 2 through which secured are the Anti-Vibration Rods 3-as many as 're quired'dependent on Turbine size. Both corners of the Leading Edge are distanced and held by the Primary Intake Stay 4.

Owing to the large Casing Surface Area, not usual in other Wind Machines, a Lighning Conductor 5 is vital for long term safety of personnel, electrical equipment, and the Turbine. Considerable currents could be induced from lightning strikes closeby. This standard could be reduced to 'general earthing' in areas of Low Average Wind Velocities, where the casing could well be made up from plastic sheeting, plywood, canvas or doped fabric.

During the length from point "A" to point "B", the Turbine Casing Taper imparts a Compressive Effect to the incoming Wind at a Standard Ratio of 2:1. This Effect is to speed up the Wind prior to entering the Vortex Chamber and is regulated by the Compression Stay 6. The Storm Bar 7 as bolted to the Primary Intake Stay 4, takes the Horizontal Stresses of any Wind velocity. At point "B", the Secondary Intake Stay 8, governs the width of the final intake into the Vortex Chamber. The length of this Stay 8 is the same as the radius of the Vortex Chamber. If the size is longer, the net Vortexor Speed is Lower, if smaller, there is loss of net power. At this point, the wind is formed into a narrow band of concentrated wind which after point "B", begins affecting the blades.Point "B", is also the internal end of the Spiral Casing, finishing integral with the Crane Rail 9, which runs the length of the Turbine. This name underlines its required strength, and signifies that lifting devices can be suspended to run along here thus facilitating blade installation or removal.

The Bearing Steady Strut 10, which should always be removable, so as to allow a removal of the Vortexor complete, maintains the Side Main Frame stability with anti-twist support.

The Main Side Frame 11 indicates the full assembly, with the separate triple, equally spaced armed Bearing Support Frame 12 added, containing the taper roller bearing housing Er thrust bearing unit according to choice and holds, at all times centrally, the Vortexor Shaft 13, (blades and balances complete).

The Vortexor Assembly spins in the Vortex as generated in the Spiral Casing, the Casing following the shape of the Main Side Assembly 11, with the consequential Power from the Wind being converted to Rotary Movement and transmitted as Shaft Brake Horse Power via the Drive Shaft 14, to power any form of machine so matched by appropriate gearing.

An Anti-gust Locking Ring 1 5 is provided in the base of the Vortex Chamber, for positively holding the Vortexor still during maintenance, since the Turbine is sensitive and responsive to 'stray gusts of wind'.

The Turbine Supporting Framework 16, should be robust and wide enough to cope with severe lever effects generated by the distance from the Frame 1 6 to the Leading Edae 1. On account of this, the Central 360 Turntable Plate 1 7 would be better supporting a "Turntable" type swivel rather than a central pin.

In continuing, Two Main Vertical Backbones 1 8 are required as a basic support for the Casing Materials, this would include in larger Turbines, a lighter secondary network of struts to affix the Casing materials chosen. So long as metal casing materials are used, only three main Tie-bars 1 9 will be required. If fabrics are used, then a Diagonal Bracer, (not shown), would be required for extra stability. All fixings should be of a Shake-proof character, with Stainless/Monel metal in coastal locations. The Turbine is fundamentally robust yet simple, with the all metal one expected to give a Life of 1 50 years sevice.

General Front Elevation.

Fig. 2 is a general view of the front or 'Exposed Area' of the Turbine with front panels cutaway to show the Vortexor in fuller detaii.

The observer would be standing in front of the machine with his back to the Wind. The Figure shows the general layout of the Vortexor 20, complete with three identical Blades 21, affixed ridgedly to the Vortexor Shaft 13, together with each Blade's individual Dynamic Balancing Rods 22, with their adjustable Balance Weights 23. It can be noted that the Blades overlap each other by a 1 /5th in their rotary tracks. The Blades are fixed to the Vortexor Shaft 1 3 by a Blade Spigot 24 which joins oppositely, the Balance Rod 22.

Further; at the exit end of the Blade, a simple additional fixing point the Oscillation Steady 25 holds the blade length secure from possible Vortex Buffeting, particularly in the larger size Turbines.

The middle blade is centrally situated on the Shaft, with the other two equally spaced between the central Blade Spigot 24 and the ends of the Shaft 13, but not the whole gross length of the Turbine complete. Some free space is needed for the Vortex to form cleanly at each end of the Shaft and some direct power must be sacrificed from the blades for this assists spent air to exit.

The Blade, for simplicity, has a concave form cupping the air-flow. The Blade's curve is that same curve as formed by the Vortex Chamber.

The Blade does not possess any 'development', i.e. a double curve form, but instead, the Edge of the Blade adjoining the Main Shaft is cut to suit the required profile along the length it touches whilst the Blade is Set at 18 , where the length of the shaft is taken as 0o, as per Fig. 2.

Blade Clearance from the Casing sides should be approximately 5% of the Blade Width. If clearance is less, the Blade Tip will drag in the Boundary Layer of Air, which cushions directlv, in a static wav. aaainst the inside of the Vortex Housing and will tend to brake the gaining of its full rotational speed.

Whilst air will bleed past this Clearance during low wind speeds, it becomes unimportant at its Rated Speed. Further, air will also bleed from the sides of the Compression Area during low and variable Wind Speeds. Whilst Side Panels, (not shown), can be provided to enclose the area from "A" to "B", surplus Wind passing by the Sides 11 tends to act as a balancing compressive factor itself thereby reducing the escape of Wind.

With Blade Set = 18 ( + 1"), then the wides part of the Blade is first to dip into the incoming Wind and opposes its flow. This therefore, lets the rear of the Blades run with the rotation, i.e: with the Blade offering the least resistance to the 'Vortex Development Spiral Track' to the Exit. Although, therefore, it would then seem-that the Blade Set is trying to direct the Air to the Vacuum Side, setting the Blades so as they 'look right', results in sluggish performance. Again, small amounts of air will bleed from the Vacuum End until the Turbine is receiving sufficient Pressure of Wind for the Vortex to build to its full Tornado form and strength.

Since water eventually attaching the bearings is feared as the main cause of any breakdown, Dished Water Thrower Rings 26 ought to be provided each end adjacent to the Bearing Scale as mounted integral with the Bearing Support Frame 1 2. This is vital in Vertical Mountings.

To minimise seal damage during service in Artic Conditions, Carbide Tipped Ice Cutters 27 ought to be included abutting the Seals.

The Blade could be classed as a semilift/drag type, with the Blade assuming a 'lift character' in its first position by Point "B", thereafter changing into a semi-drag-axial type.

Full 'lift' type blades can be installed on the Vortexor, and although experiments are still continuing with these, complex blade development shapes are required and the Self-governing character is reduced, with, so far, only a quarter nett increase in Specific Speed realised. The ability for the Turbine to be built with simple hand tools and reclaimed materials in areas of workshop deprivation is also lost.

The Vortexor is best balanced removed from the Turbine Casing; individual Dynamic Balancing blade by blade on levelled knife edges is strongly advised. Unlike three bladed Propeller Turbines which can be balanced in a fairly straight forward manner, each blade on the VVT, not being on the same rotational plane, must be separately balanced.

However, in severe icing conditions, when most Turbines have to be stopped on account of damaging unbalance or even loss of aerodynamic shape, the VVT will still be able to run.

Not only will it run in severe icing conditions of unbalance, but in some types of wet snow, a readjustment of that Blade Balance next to the Exit may well have to be donerather similar to the Orbital Sander systempurposely to unbalance the machine so keeping sticking snows on the move.

Dry snows and fine snows pass through the Turbine with no trouble, yet if too much trouble is experienced with heavy snow collecting at the base of a Horizontal Turbine, Snow Slats 28 opening in the Back of the Casing at Point "B" could be added to divert sliding snow in a continuous operation. Since there is no Water Power in Arctic Regions, it is vital that a Prime Mover can be relied upon to continue operating in the severest of bizzards. Hence the dwell on such details.

With two tie-bars 1 9 reshaped into sledgerunners, on calm days Turbines complete could be towed to Sites by 'Snow-cats', erected 8 anchored via Octopus style legs.

Specific Speed.

This is where the Turbine begins not to follow the usual rules. It is admitted that this character is not as yet fully understood. In comparing Propeller Turbines, it is generally known that their Rated Speed is from 80 to 90 revs per minute for a 40ft (14m) Diameter One, with 35 to 40 r.p.m. for a Top Class 100ft. (34m) Diameter one, and with the average Dutch Traditional Windmill (80ft) known to turn at 10 to 20 r.p.m.

With the VVT, the nett Specific Speed is poor in its small sizes, for examples, a 4ft one runs at only 750 r.p.m., whereas a Propeller of the same 'Swept Area' (8 to 10 sq ft.) runs at about 1,500 r.p.m.

However, a tiny hand held cardboard version of the VVT (6 inch), hardly reached 1000 r.p.m. If this comparison is maintained, as expected, a VVT size equivalent to a 40ft Diameter Propeller Turbine is expected still to be turning at a speed too fast to count by eye comfortably, i.e. 250 r.p.m., with One Megawatt VVT's expected to run at over 100 r.p.m.

In refering to Fig. 3, it can be observed that whereas this VVT machine is not too fast in its smaller sizes, it really comes into a Class of its own in the larger sizes. The Figure shows at a glance the advantages of the Pressure differences, i.e: the High Velocity Pressure Area of the Wind, high up in smooth airflow, collected in the top of the machine and being brought down with increasing advantage to the Low Pressure Area.

With this layout therefore, a better overall efficiency can be expected than the same size Propeller Turbine, bearing in mind that the blades of such machines dip into more feeble air and Tower Shadow. Important factors of gradually destructive Blade Flexings, viz: of Gravitation Effect, Wind Sheer Er Shift, Tower Shadow Vibration, Blade Root Metal Fatigue, Blade Stall and Noise all solved in one fell swoop. VVT's seem to be silent while running-no blade 'swish'. Further, the important parts, being not too far off ground level, bring maintenance of and access to key parts within the limits of any engineer with common equipment rather than the realm of Steeplejacks alone.

Whilst no large VVT Turbines have been built to date, it would seem that the Specific Speed is likely to increase proportionally to the size. That is, where a small VVT type Turbine runs slow in comparison to the very high Specific Speed of a Propeller, the actual REAL Specific Speed of a larger VVT will be several times above that able to be developed by the Propeller. Thus the Shaft r.p.m. of a Propeller Turbine is frustrated by the sheer desperate circular speed the Blade Tip has to travel per revolution in its larger sizes, the Vortexor Blades gain their speed from the Vortex Whirl generated in the Chamber. Thus it could well be expected that the largest VVT currently envisaged, (11 megawatts, inbuilt into tops of Glens), could be still expected to exceed 20 r.p.m.This size Turbine is quite a practical proposition, with the civil engineering works similar to present day medium sized Hydro-electric Schemes Er Bridge Building.

General Considerations Vertical VVT Turbines are mostly likely to be used for integrating into buildings of certain towns and cities, where with careful wind measurement, the majority of the Turbine can be hidden. In ideal locations, or through advanced Planning, a multiple entry Vertical Turbine could be constructed, where building layouts up to a mile distant could assist the ducting of the Winds from the Three main directione West, North-East, 8 South.

The rectangular requirement of the Turbine enables hitherto impractical Wind Sites to be developed; inbetween exposed housing; on top of certain roofs and barn buildings. The Turbine could be supplied in its basic form of Vortexor, Side frames Er bearings to be built into a Casing made entirely of stonework.

There are many possibilities.

As the Turbine is sensitive to gusts, unlike the open blade turbines, where the Gust is able to screw its way through the blades somewhat, it may be good practice to include a Friction/slip Clutch before the speed increasing Gearbox, or sheering of keys or a whole shaft may result.

Governing.

It is not the intention to dwell on this point, since the invention of a Fine Electronic Governing by Mr. Gerry Pope of G.P. Electronics at Bovey Tracey, Devon, has eliminated the need for complex mechanical governing methods on Water Turbines and Wind Machines. However, where a coarse governing is required for non-electrical machines driven by the VVT Turbine, or as a safety factor to cover loss of Excitation on an Alternator, then a butterfly type Governing Unit bolted on to the EXIT side of the Turbine will control up to two thirds of the speed/power output. Complete speed control to a Halt, will necessitate a Transmission Drum Brake, or by turning the EXIT side into the wind.

Speed increasing Gearboxes are expected to be mounted directly on to the Vacuum Side output shaft, with the larger Generators taking a Right Angled Drive to be bolted onto extended fixings added to the Side Frame.

For 'Stand Alone' Synchronous Sets, a Flywheel on the Generator would be helpful, particularly in difficult, gusty sites.

Luffing.

The Turbine is not 'Wind Seeking', and must be mechanically turned square into the Wind. With small sizes, this can be done by hand, with the larger, servo-systems will be required. The shape of the Turbine Casing however lends itself to the automatic 'fan-tail' luffing device as used on conventional Windmills, with a direct shaft drive suitably wormgeared dropping down-to the turntable area.

On a failure of the luffing mechanism, (sheared pins or keys) the Turbine will tend to turn out of the Wind by 180 .

Notes.

Rated powers are based on the assumed wind velocities of 25/30 m.p.h. with the exception of the 4ft test model, rated at 30 watts, 1 2v at 35 m.p.h. WT Turbines run backwards very badly. It will be quite easy to wander about turbines over 30ft length; adequate fencing ought to be provided to prevent this. Thermal Gusts will start Turbines.

VVT Turbines over 50ft. (18m) will begin to support large diameter Shafts, since part of the Formula directing Turbine design, is for the Vortexor Shaft Diameter to be 10% of the overall Turbine nominal gross length. Therefore a 50ft Turbine would have a Shaft of 5ft Diameter. From this size upwards, it is expected that an additional rotational power force, namely the 'Magnus Effect', (the ability for the Wind to turn a plain cylinder), will become very sympathetic to the Machine, perhaps adding up to 8% more net power to the Shaft.

With the Shaft taking the place of the Vortex's Vacuum Core, bearing in mind the swirling Vortex Flow being pressed tight against the Shaft as its exits spirally, then adding a Spiral well assist in extracting extra power from the available Wind.

At present, the efficiency noted in a 4ft one seems to be no better or worse than the equivalent size Propeller turbines. Better efficiencies could therfore be reasonably looked forward to in the larger sizes, being as well freer from prominent Boundary Layers and transmission frictions.

It can be deducted therefore, that unlike all other known Wind Power Machines, the bigger the VVT Turbine gets the stronger and more efficient it will become. Even in its most basic form, without effecting it with ongoing aero-dynamic research sophistication, its efficiency is quite 'competitive'. It is thought that while this will be done eventually, the current attractiveness for its ease of construction in developing World Areas is likely to be spoiled.

The 'No Load' start up performance compares well with Propellers, beginning to turn when the Wind reaches 5 M.P.H. The Shaft Torque Graph Curve steepens with Turbine Size.

The most serious disadvantage is its ugliness. It has no aesthetic or 'Traditional much painted Windmill" at all. It is the biggest worry.

As there is no sign of movement outside the machine, there is some concern about birds, especially at coastal sites, flying into the intake. Advice is being sought on the matter.

The Water Version.

The VVT Turbine, being essentially a velocity machine, can be adapted to gain power from, and running fully immersed in flowing water.

Its uses would be to develop deep rivers and/or tidal estuaries where damming for Kaplan Turbines is not practicable because of Navigation or Environmental reasons. Certain tidal races close to shore could be tapped with the VVT Turbine also.

Whilst the turbine follows the general Principle, certain alterations are required for water as follows: As water is not compressible, there must be no tapered inlet form. The entry must be the same regular size as the Vortex Chamber.

The Blade Vortex Housing Clearance should be 30% of the Blade Width.

The Vortexor Shaft one third less than that for Wind. i.e. a 20ft Turbine should have a shaft 1 6 inches diameter.

The general construction of the turbine should be very heavy; more of interest to the shipbuilders. Major drag forces act on such turbines; many times that of Wind Turbines.

Bearings should be water lubricated; meaning, no attempts to use sealed bearings should be made.

It is unlikely, in practice, that generators be direct driven by these turbines. The turbine should be sturdy and well anchored with heavy chains in an area of flowing water where the core or central flow of water gains access to the turbine inlet.

A three stage centrifugal high delivery pump capable of a 300ft head pressure should be added to the fully immersed Turbine to engage by a simple dog drive on the Turbine shaft. A suitable size pipe is then lead from the pump to the nearest piece of land or quay.

The Turbine will then power the pump through a 10:1 speed increasing gear, the high pressure water then being supplied to a matched Standard Turgo Impulse Water Turbine as invented and marketed by Messers Gilkes Ltd, Kendal, Westmorland.

The rest is best left to the Hydro-electric engineers.

For contraflow tidal operation, the VVT casing should be allowed to turn with the ebb Er flow.

Claims (12)

1. A VORTEX VELOCITY LINEAR TUR BINE comprising a Cased Turbine assembly, containing one main moving part rotating centrally, because of, and within a generated Vortex as formed by a Chamber in which Air or Liquids are received in a Linear Fashion, that is to say, evenly approaching the entire length of the rotating shaft at 90 .

2. That the machine as titled in Claim 1, hereafter referred to as the VVT, receives Wind by means of a Venturi Shaped opening the full length of the VVT, continuing through a Taper Shape thereby imparting a Compressive effect to the Wind Flow.

3. That the "6" Shaped Casing continues to turn the Wind through 45 to 180 from the Ambient Wind Flow, which ever way the Turbine is installed, to spin the Wind in a Circular Vortex Chamber about the centrally mounted full length Bladed 'Rotor'. (Vortexor).

4. That the Standard Base VVT Machine contains a large shaft of a diameter not more than 10% of the overall chosen length of any Turbine, on which are mounted at least equally spaced, fixed curved blades (High Lift or Medium Speed character) being set at each equal Third of the shaft's Circumference.

5. That the Basic PRINCIPLE of the Standard VVT is able to operate in any Plane thus demonstrating its Adaptability to Site Conditions, at any angle from Horizontal to Vertical, the latter to which two additional tapered Wind Openings could be additionally allowed to cater for differing main Wind Directions.

6. That the VVT can be of a static installation or able to revolve 360 to line up square to the daily Wind Direction.

7. That by removing the Taper on the entry; reducing the Blade size and ensuring heavy construction of the Turbine, then the VVT would be appropriately suitable for gaining power from flowing water in marginal conditions, where Static Pressure Turbines are not allowed or impracticable.

8. That the VVT is a 'Class of Prime Mover', able to power most well known rotating machines through suitable gearing.

9. That the VVT in its smaller sizes, could be made substantially as a Mobile Unit either Wheeled in itself, on lorries or sledges.

10. That governing of the VVT is achieved by the addition of a standard Butterfly Design Valve mounted centrally on the EXIT end, where Fine Governing by Electro-magnetic or Electronic means are not applicable.

11. That to gain double the power at the same required shaft speed in certain favourable conditions, two turbines (a double rotor) may be integrated with each other, or otherwise connected in line or side by side, suitably coupled.

12. With attention to the detailed PRINCI PLE as is the WT as summaried in Claim 1; clarified by others, that for the purposes of Sound Engineering Practice in compliance with Site Conditions, additions to the PRINCI PLE of the VVT such as: larger intakes, long ducting to place entire machine in a Low Pressure Area, or Low Pressure inducing shrouding on/near the EXIT-then such additions are claimed as such and not as a new invention. Drawings indicate the PRINCIPLE and main STRESSES only; not as a blueprint for a finished Product.