GB2062118A

GB2062118A - Improvements in or relating to a turbine

Info

Publication number: GB2062118A
Application number: GB8035424A
Authority: GB
Original assignee: COVEBOURNE Ltd
Current assignee: COVEBOURNE Ltd
Priority date: 1979-11-05
Filing date: 1980-11-04
Publication date: 1981-05-20
Also published as: GB2062118B

Abstract

A turbine 1 comprises a rotatably mounted rigid disc 2. Channels 4, equi-spaced around two pitch diameter circles extend through the disc 2. The axis of each channel lies at an angle to the plane of the disc, but not perpendicularly to the plane of the disc, and in a plane which is both perpendicular to the plane of the disc and tangential to the pitch diameter circle at a point where the axis of the hole 4 crosses the pitch diameter circle. The channels may be extended by tubes 7, which may be straight or curved. When the disc 2 is placed in a flow of fluid, e.g. water, the fluid passes through the channels 4 and the disc 2 rotates. In an alternative embodiment, the tubes lie between two coaxial radially spaced annular members, the inner annular member being attached to a central boss by three inclined arms. <IMAGE>

Description

SPECIFICATION Improvements in or relating to a turbine This invention relates to a turbine.

This invention seeks to provide a turbine that is simple to manufacture.

According to the present invention there is provided a turbine comprising a rotor and means for mounting the rotor for rotation about an axis; the rotor including means defining at least one elongate substantially cylindrical channel open at two opposed ends, the axis of the channel being inclined to the said axis of rotation of the rotor such that passage of fluid through the channel will cause the rotor to rotate about the said axis of rotation.

Preferably, a plurality of the channels is provided, the axes of the channels intersecting a first plane perpendicular to the said axis on a first pitch diameter circle.

Advantageously, a further plurality of channels is provided, the axes of which intersect the said plane on a second pitch diameter circle which is concentric with the first pitch diameter circle.

Conveniently, the axis of each said channel is inclined at an angle to the said first plane and also lies in a second plane which is both perpendicular to the first plane and tangential to the respective pitch diameter circle at the point where the axis of the said channel intersects the said pitch diameter circle.

Suitably, the or each channel is formed at least partially by a tube.

Preferably, the rotor comprises a disc parallel to the said first plane.

Advantageously, the disc is provided with at least one hole passing therethrough to define at least partially the channel or channels.

Each channel may be formed by one of the said tubes extending from one of the said holes and, preferably, each tube is the same cross-sectional shape as the hole from which it extends.

Conveniently, the rotor comprises a second disc, parallel to the first disc, and provided with corresponding holes so that each channel is formed by two holes and a tube, and preferably the discs lie at opposed ends of the tubes.

The tubes may lie between at least two annular members coaxial with the said axis of rotation and preferably the innermost annular member is connected to a central axial boss by a plurality of radially extending arms. Conveniently the arms are planar and are inclined to the said first plane.

Conveniently at least one end of each of the tubes lies in a respective plane substantially parallel to the said first plane, alternatively, at least one end of each of the tubes lies in a plane inclined to the said first plane.

The channel in any of these embodiments may be linear or curved, and if it is curved the curvature may be such that the axis of the channel is a constant distance from the axis of rotation of the member, this distance being measured, at any point, in a plane perpendicular to the axis of rotation of the member.

Conveniently, the member is fixedly mounted on a shaft passing perpendicularly through the member for co-rotation with the shaft.

Advantageously, this assembly of shaft and turbine may be mounted in a means for providing a flow of fluid through the channels in the member, a suitable means being a substantially cylindrical pipe.

In order that the invention may be more readily understood, and so that further features thereof may. be appreciated, the invention will now be described by way of example, with reference to the accompanying drawings, in which: Figure 1 is a view in plan of a disc constituting a turbine in accordance with the present invention; Figure 2 is a vertical sectional view of a part of the disc of Figure 1 showing one hole and corresponding tube; Figure 3 is a vertical sectional view of a portion of a disc similar to that shown in Figures 1 and 2 but constituting a different embodiment of the invention; Figure 4 is a side elevational view of a turbine assembly containing a disc constituting a turbine in accordance with the invention and an associated shaft with parts thereof cut away; Figure 5 is a sectional view taken along the line V-V in Figure 4;; Figure 6 is a sectional view taken along the line VI--VI in Figure 4; and Figure 7 is a plan view of a second embodiment of a turbine in accordance with the invention.

Referring to Figure 1, a turbine 1 comprises a circular disc 2 of rigid plastics materials with a bore 3 in the middle, the axis of which is normal to the plane of the disc. A plurality of channels extends through the disc 2, these channels being defined by holes 4, the axes of which lie on two concentric pitch diameter circles having, as their centres, the axis of said bore 3. The holes 4 are of circular section and each is formed with the axis thereof lying at an angle to the plane of the disc, but not perpendicular to the plane of the disc, and in a plane which is both perpendicular to the plane of the disc and tangential to the pitch diameter circle at the point where the axis of the hole 4 crosses the said pitch diameter circle. The axes of the holes 4 are all inclined in the same rotational sense.Since the circular cross-section holes 4 are inclined, the apertures formed in the surfaces 5 and 6 of the disc by each hole are elliptical. The holes 4 are equally spaced around each of the pitch diameter circles.

On one side of the disc 2 the channel defined by each hole is extended by a straight sided tube 7 of the same internal cross-sectional shape as that of the hole 4, and with the inside surface 8 of the tube 7 flush with side of the hole 4. The end 9 of each tube 7 which is distal to the disc 2, as illustrated in Figure 2, lies in a plane substantially parallel to that of the disc 2. In the alternative embodiment illustrated in Figure 3, the plane in which the end of the tube lies is inclined to the plane of the disc so that the inclined plane intersects with the surface 5' of the disc to form a line substantially parallel to a line extending from the centre of the disc to the centre of the aperture formed by the respective hole in the said surface 5'. The inclined plane may be inclined at any angle to the plane of the disc up to and including 900.

Typically, the plane may be inclined at an angle of 200.

It will be appreciated that the effect of the tubes 7 is to increase the length of the channels formed in the disc. This can also be achieved by forming holes 4 of the type described above in a thicker disc.

In one specific embodiment of the invention, which is the embodiment illustrated in Figures 1 and 2, the disc is horizontal and has a diameter of 1 50 millimetres and thickness of 6 millimetres, the central bore 3 has a diameter of 9.5 millimetres, and the two pitch diameter circles have radii of 28.5 and 60 millimetres respectively.

The tubes 7 extend 19 millimetres beyond the upper face 5 of the disc, and each is inclined at an angle of 450 to the vertical, with the plane of the end of each of the tubes being parallel with the plane of the disc 2. As illustrated in Figure 1, there are four holes and tubes arranged around the inner pitch diameter circle and eight holes and tubes arranged around the outer pitch diameter circle.

Referring to Figures 4 to 6, in a turbine assembly incorporating a disc 2 as described above a vertical shaft 10 passes perpendicularly through the centre bore 3 of the disc 2 and is firmly attached to the disc 2. The shaft is located in a vertical, substantially cylindrical pipe 11, the diameter of which at the region closest to the disc 2 is such that only a small clearance exists between the outer edge 12 of the disc 2 and the inner surface of the pipe 1 The shaft 10 is rotatably supported at a point adjacent the upper end thereof on bearing 13 and at the lower end thereof on bearing 14 to allow free rotation of the shaft.

The bearing 13 is provided centrally in a plate 1 6 which closes the upper end of the pipe 11 and which is held in place by retaining pins 1 6a. A portion 17 of the shaft 10 protrudes above the plate 16 and drive belts or gears or wheels (not shown) may be connected to this portion. The bearing 14 is held in a position in the centre of the pipe 11 by three arms 18 that extend radially inwards from the wall of the pipe 11. Thus a flow of fluid in the pipe 11 can readily pass between the three arms 18. A second, downwardly inclined, pipe 15 communicates with the first pipe at a point above the disc 2.

In operation of the illustrated turbine assembly, water or some other fluid is introduced into the main pipe 11 via the second pipe 15 from a suitable source having an appropriate pressure level. The fluid will flow down the first pipe 11 and through the channels formed by the holes 4 and tubes 7, thus causing the disc 2 and hence the shaft 10 to rotate. The rotating protruding portion 17 of the shaft 10 which extends above the upper set 13 of bearings may be used as a source of power which may, for example, be used to generate electricity by means of a dynamo electric generator.

It will be appreciated that whilst the invention has been described with reference to one embodiment, many variations are possible. For example, two discs with holes may be provided with tubes extending between the holes in the two discs. Alternatively, the tubes may extend on both sides of only one disc. Furthermore, the tubes may be omitted if a single disc of appropriate thickness is used. The specific angles specified above may be varied and whilst in the described embodiments the channels formed by the holes and tubes are linear, the channels may in some embodiments be curved, so that the axis of the channel is a constant distance from the axis of the central bore when measured, at any point, in a plane perpendicular to the axis of the bore.It will also be appreciated that whilst in the embodiments described above the flow of water through the disc has been provided within the confines of a pipe, it would be perfectly possible to mount the shaft and disc such that the disc is wholly or partially immersed in an existing flow of water, such as might be found in a stream, a waterfall or a tidal basin.

A second embodiment of a turbine in accordance with the invention will now be described with reference to Figure 7 of the drawings. A turbine 1 9 comprises: a central cylindrical boss, adapted to be mounted for rotation about the axis thereof on a shaft passing through the centre of the boss; three planar arms 21 set at 1200 to one another around the circumference of the boss and extending radially outwardly therefrom; an inner ring 22 attached to the ends of the three arms; eight tubular members 23 spaced evenly around the outer periphery of the inner ring 22 and attached thereto; and an outer ring 24 surrounding, and attached to, the eight tubular members 23. The boss 20, the inner ring 22 and the outer ring 24 are all coaxial, and the entire turbine 1 9 is a rigid assembly mounted for rotation about the axis of the boss 20.

The plane of each arm 21 is inclined at 450 to the axis of the turbine and the axis of each tubular member is inclined at 450 to a plane passing perpendicularly through the axis of the turbine in an arrangement which is similar to the inclination of the holes 4, described in connection with the first embodiment.

The tops of the tubular members all lie in a common plane which is perpendicular to the axis of the turbine and, likewise, the bottom of all the tubular members also all lie in a common plane perpendicular to the axis of the turbine.

In one particular example of the embodiment df the turbine presently being described, the diameter of the outer ring 24 is approximately 155 mm, the diameter of the inner ring 22 is approximately 90 mm, the diameter of the boss 20 is approximately 25 mm, the slant height of each planar arm 21 is approximately 25 mm and the slant height of the tubular members is approximately 45 mm. The various parts of the turbine 1 9 are constructed from mild steel and are welded together to form the turbine.

It has been found that a turbine constructed as above with respect to the second embodiment is lighter than a turbine constructed in accordance with the first embodiment and, for a comparable output (when mounted in a pipe of the type shown in Figures 4 to 6), there is a reduction in the resistance to the flow of the fluid past the turbine.

In addition, it has been found that the more open arrangement of the second embodiment is better suited than the disc arrangement of the first embodiment for use in open water, that is to say without the use of a pipe surrounding the turbine.

Tests have indicated that a turbine with a diameter of approximately 1 metre placed in a 1600 metre per hour water flow might give a power output in the order of 3 kilowatts. It has also been found that a turbine in accordance with the invention will operate satisfactorily in siltladen water.

It will be appreciated that, instead of mild steel, a turbine in accordance with the invention could be constructed from, for example, a plastics material such as a glass-fibre reinforced plastics material. In addition, two or more circles of tubes could be arranged coaxially and sandwiched between three or more rings. Whilst turbines as described above may be used to drive dynamo electric generators, the turbines may also be used as a source of usable power for other purposes.

For example, a pump may be integrally mounted with the turbine to pump water from the flow that is driving the turbine. Such a device may be used to lift water for irrigation purposes.

A further use for turbines in accordance with the invention is to provide an auxiliary source of power for yachts and similar vessels. Thus the turbine may be mounted on an appropriate framework or the like connected directly to the vessel so as to be at least partly submerged so that on movement of the vessel through the water the turbine rotates, or on movement of water past the vessel (in either direction), for example when the vessel is moored, the turbine will rotate. When the vessel is in motion, the turbine may be lifted out of the flow of water relative to the vessel or alternatively may be left the flow to supply energy to a dynamo electric generator. When the vessel is moored in a river or tidal flow, the turbine may likewise be used to supply power, thereby eliminating the use of, for example, a diesel electricity generator, or minimising the drain of current from storage batteries.

Claims

1. A turbine comprising a rotor and means for mounting the rotor for rotation about an axis, the rotor including means defining at least one elongate substantially cylindrical channel open at two opposed ends, the axis of the channel being inclined to the said axis of rotation of the rotor such that passage of fluid through the channel will cause the rotor to rotate about the said axis of rotation.

2. A turbine according to claim 1, in which a plurality of the channels is provided, the axes of the channels intersecting a first plane, perpendicular to the said axis, on a first pitch diameter circle.

3. A turbine according to claim 2 wherein a further plurality of channels is provided, the axes of which intersect the said plane on a second pitch diameter circle which is concentric with the first pitch diameter circle.

4. A turbine according to claim 2 or 3 in which the axis of each said channel is inclined at an angle to the said first plane and also lies in a second plane which is both perpendicular to the first plane and tangential to the respective pitch diameter circle at the point where the axis of the said channel intersects the said pitch diameter circle.

5. A turbine according to any one of the preceding claims wherein the or each channel is formed at least partially by a tube.

6. A turbine according to any one of the preceding claims wherein the rotor comprises a disc parallel to the said first plane.

7. A turbine according to claim 6 wherein the disc is provided with at least one hole passing therethrough to define at least partially the channel or channels.

8. A turbine according to claim 7 when dependent on claim 5 wherein each channel is formed by one of the said tubes extending from one of said holes.

9. A turbine according to claim 8 wherein each tube is the same cross-sectional shape as the hole from which it extends.

10. A turbine according to claim 8 or claim 9 wherein the rotor comprises a second disc, parallel to the first disc, and provided with corresponding holes so that each channel is formed by two holes and a tube.

1 A turbine according to claim 10 wherein the discs lie at opposed ends of the tubes.

12. A turbine according to claim 5 wherein the tubes lie between at least two annular members coaxial with the said axis of rotation.

13. A turbine according to claim 12 wherein the innermost annular member is connected to a central axial boss by a plurality of radially extending arms.

14. A turbine according to claim 13 wherein the arms are planar and are inclined to the said first plane.

1 5. A turbine according to claim 5 or any preceding claim dependent thereon, in which at least one end of each of the tubes lies in a respective plane substantially parallel to the said first plane.

16. A turbine according to claim 5 or any one oft claims 6 to 14 when dependent on claim 5 in which at least one end of each of the tubes lies in a plane inclined to the said first plane.

17. A turbine according to any one of the preceding claims in which the or each channel is substantially linear.

18. A turbine according to any one of claims 1 to 16 in which the or each channel is curved.

19. A turbine according to claim 18, in which the curvature of the or each channel is such that the axis of the channel is a constant distance from the said axis of rotation, the said distance being measured, at any point, in a plane perpendicular to the said axis of rotation.

20. An assembly of a turbine according to any one of the preceding claims and a shaft passing perpendicularly through the rotor for co-rotation with the rotor.

21. An assembly according to claim 20, the assembly being mounted in a means for providing a flow of fluid through the channel or channels in the rotor.

22. An assembly according to claim 21, in which the means for providing a flow of fluid comprises a substantially cylindrical pipe through which the fluid flows, the rotor being circular and having such a diameter that all points on the periphery thereof are substantially adjacent the inner periphery of the pipe.

23. A turbine substantially as herein described with reference to and as shown in Figures 1 and 2 of the accompanying drawings.

24. A turbine substantially as herein described with reference to and as shown in Figures 1 and 2 as modified by Figure 3 of the accompanying drawings.

25. A turbine assembly substantially as herein described with reference to and as shown in Figures 4 to 6 of the accompanying drawings.

26. A turbine substantially as herein described with reference to and as shown in Figure 7 of the accompanying drawings.

27. Any novel feature or combination of features disclosed herein.