GB2265185A

GB2265185A - Pumps having spirally-coiled tubing.

Info

Publication number: GB2265185A
Application number: GB9305922A
Authority: GB
Inventors: George William Worrell
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-03-20
Filing date: 1993-03-22
Publication date: 1993-09-22
Anticipated expiration: 2013-03-22
Also published as: GB2265185B; GB9305922D0

Abstract

The open, outer end of spirally-coiled tubing 1 carried between flanges 3 of a rotating spool 2, moves first down and then up through the interface between air 9 and water 8 to admit quantities of air and water in turn to the tubing 1. Continued rotation translates the successively-admitted quantities of air and water radially inwards within the tubing 1 for discharge under pressure from the inner end 5 of the tubing into a chamber 6. As a modification, the initial length of the coil at the open end (44, Fig. 6) may be of enlarged diameter and have an air-bleed hole (47) to facilitate entry of water. More than one coil may be used, the coils being carried side-by-side with their open ends (24, Fig. 3) distributed angularly from one another around the rotor (20). Rotation of the rotor may be powered by wave or tide movement, or by wind and/or water-flow, and the pumped air and water may be used to drive a turbine for electricity generation (Figures 4 and 5). <IMAGE>

Description

Pumps This invention relates to pumps and methods of pumping fluids.

According to one aspect of the present invention there is provided a pump having a rotor which is for rotation through the interface between bodies of two different fluids and which involves an elongate passageway for containment of quantities of both fluids, wherein the passageway extends spirally radially of the rotor with a cross-sectional area that decreases or is substantially constant inwardly of the spiral, and the passageway is open at one end to admit quantities of fluid from one body and then the other in turn as the rotor rotates through the interface such that with continued rotation of the rotor the successively-admitted quantities of the two fluids are translated radially with respect to the rotor for discharge from the other end of the passageway.

It has been found that with a pump of this form operated in air at the surface of a body of water, useful pumping of air and/or water can be achieved. As rotation of the rotor in this case causes the open end of the passageway to move repeatedly down through the water, up through the air and down again through the water, so a quantity of water, then of air, and then of water again, are admitted to the passageway. The initial quantity of water admitted moves further along the passageway under gravity as the open end rises through the water surface, so as to be followed into the passageway by a quantity of air that is admitted until the open end again enters the water.

As the rotor continues to rotate, so further quantities of water and air are admitted in turn, and the quantities earlier admitted shift further along the passageway.

Where the rotor is of a form in which the passageway spirals inwardly from the open end, the individual quantities of water and air are in this way translated radially inwards as the rotor rotates. This causes a build up of pressure within the passageway under which the water and air discharge from the other, inner end of the passageway. The pump, therefore, acts as an air pump, as a water pump, or as a pump for both. The relative quantities of air and water pumped depends on the depth to which the pump rotor is immersed in the water at the water surface, the deeper the greater the water-quantity.

The passageway of the pump according to the present invention, may be formed simply by tubing that is wound upon itself. The tubing may be wound on a spool or reel, and such spool or reel may have flanges for constraining the tubing to retain it in the spirally-wound configuration. The tubing, in this respect or otherwise, may be constrained so that each turn runs directly on the next in a true or near-true Archimedean spiral, but this is not necessarily so, in that the spiral need not be regular and it would be possible even for the turns to run side by side over part of the tubing length.

The said other end of the passageway may vent into a chamber which is located on the rotational axis of the rotor for separation of the fluids from one another therein. Fluid discharged from that end may be supplied from the chamber or otherwise, to drive a turbine.

The pump may be driven in rotation by means of, for example, wave and/or wind power, or by water flow in the manner of an undershot, or overshot, water wheel. The rotor in the latter case may form part of the water wheel, and the water flow may be that of a river. Air pumped by the pump may be used, for example, to drive a turbine for the generation of electricity, and the water, for example, for irrigation purposes.

According to another aspect of the present invention there is provided a method of pumping wherein a rotor which involves an elongate passageway that extends spirally radially of the rotor with a cross-sectional area that decreases or is substantially constant inwardly of the spiral, and is open at one end, is rotated through a substantially horizontal interface between bodies of two different fluids such that successive quantities of fluid from one body and then the other in turn are admitted to the passageway through the open end and are translated radially of the rotor for discharge from the other end of the passageway.

I am aware of GB-A-1427723 which describes a method and apparatus for pumping fluid that, in the terms of that disclosure, depends on "continually forming U-tube manometers during the pumping operation to replace U-tube manometers being continually destroyed during said operation to maintain in existence a series of interconnected U-tube manometers opposing a head of fluid". More particularly, there is described a pump in which a coiled pipe or other enclosed conduit is rotated about the axis of the coil to immerse an inlet end of the conduit alternately in first and second fluids, and produce a pumping action through the "U-tube manometer" effect.

The possibility of the coil being of spiral configuration is stated in GB-A-1427723 with the instruction that in these circumstances, the cross-sectional area of the conduit is to decrease progressively as the radius of the conduit increases outwardly from the axis of the coil.

In distinction to this, the cross-sectional area of the conduit or gassasewav in the numP and method of Pumincr

of the present invention, isAcnstant throughout, or if there is any change, decreases inwardly of the spiral (that is to say, rather than decreasing outwardly, increases).

Pumps and methods of pumping in accordance with the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a basic form of a pump according to the present invention, in part-sectional side elevation; Figure 2 is a sectional end elevation of the pump of Figure 1, the section being taken on line II-II of Figure 1; Figure 3 is a side elevation partly in section of a second form of pump according to the present invention; Figure 4 shows the pump of Figure 3 in end elevation as used in the context, illustrated schematically, of generation of electrical power from wave motion of the sea; Figure 5 shows use of the pump of Figure 3 in an alternative system for harnessing wave movement; and Figure 6 illustrates a modification applicable to the pumps of Figures 1 and 2 and Figures 3 to 5.

Referring to Figures 1 and 2, tubing 1, which of substantially constant bore-diameter throughout, is wound on a rotatably-mounted spool 2 between flanges 3 of the spool 2. The flanges 3 constrain the coiled tubing 1 to take up a spiral configuration with each turn of the tubing 1 resting on the one before. The outer, open end 4 of the tubing 1 is secured in place resting on the tubing coil, whereas the opposite, inner end 5 of the tubing 1 opens into a chamber 6 that is mounted on the rotational axis 7 of the spool 2.

The spool 2 is mounted with its axis 7 lying in the surface of a body 8 of water. Drive applied to rotate the spool 2 thus carries the open end 4 of the tubing 1 round through the air of the atmosphere 9 during one half revolution and through the body 8 of water during the next. The direction of drive applied is, as indicated by the arrow D in Figure 1, such that the open end 4 leads in the rotation (that is to say, the opening at the end 4 impacts the water surface directly rather than being drawn down through it). As the open end 4 becomes submerged, water enters the tubing 1 and continues to enter it until the open end 4 with continued turning of the spool 4 through half a revolution, breaks through the water surface into the air again. At this stage, water fills the first half-turn of the coil of tubing 1 up to the end 4.

During continued rotation of the spool 2 through the next half revolution, air enters the open end 4 and the open end 4 is brought back to re-enter the water surface. The first half-turn of the coil of tubing 1 is now occupied by air and the quantity of water that earlier filled this half-turn has shifted back, by virtue of the rotation of the coil, to occupy the second half-turn. During the next half revolution of the spool 2, water enters the open end 4 and fills the first half-turn, the quantity of air which just previously occupied that half-turn being shifted back to occupy the second half-turn, and the quantity of water next ahead of that within the coil being shifted into the third half-turn.

The process of admitting successive quantities of water and air to the tubing 1 continues as the spool 2 is rotated and the open end 4 moves repeatedly down through the water, up through the air and down again into the water. Admission of a fresh quantity of water to the coil of tubing 1 occurs each time the open end 4 is submerged, and is followed by the admission of a fresh quantity of air each time the open end 4 moves through the air before re-entering the water. The rotation which brings each new admission of water or air, shifts the earlier-admitted series of alternate quantities of water and air, further towards the inner end 5 along the tubing 1 of the coil.Because of the radially inward spiralling of the passageway 1 from the open end 4, each shift translates the water and air inwardly and into progressively smaller half-turns of the tubing 1, so that the air is subject to progressively-increasing compression from the water. The consequence is that there is a pressure build up as rotation continues, and it is under the increased pressure this represents that successive quantities of water and air are discharged into the chamber 6.

The quantities of water and air collected in the chamber 6 are fed out via passageways 10 and 11 that extend in opposite directions along the axis 7 from the chamber 6.

The air may be separated from the water in the chamber 6 simply by inclining the axis 7 slightly from the horizontal so that with, for example, the passageway 10 higher than the passageway 11, the air is supplied via the passageway 10 and the water via the passageway 11.

In the example described above with reference to Figures 1 and 2, the axis 7 is located in the surface of the water so that substantially the same volumes of water and air are admitted successively during each revolution of the spool 2. This need not be the case, and the spool 2 may be located higher or lower in the water so that different volumes of water and air are admitted, the volume of air admitted during each revolution being increased relative to that of the water by raising the axis 7 above the water surface, and being decreased by lowering it below the water surface.

More than one coil of tubing can be used, and a pump incorporating four coils and for use, for example, in converting wave motion of the sea into electrical power, is illustrated in Figures 3 and 4, and will now be described.

Referring to Figures 3 and 4, the rotor 20 of the pump in this case includes four equal coils 21 of tubing that has a substantially constant bore-diameter throughout. The coils 21 are wound side by side on a spool 22 with flanges 23 separating them and at either end. The direction of winding is the same for all the coils 21, but they are wound with a ninety-degree staggering from one another so that the locations of their open, outerends 24 are evenly distributed around the circumference of the rotor 20. The inner ends 25 of the coils 21 are coupled into a common, central chamber 26 on the rotational axis 27 of the rotor 20.

As illustrated in Figure 4, the rotor 20 is mounted in the sea 28 with the axis 27 slightly above the water surface 29 and inclined to the horizontal. Drive to rotate the rotor 20 in a direction (indicated by the arrow D in Figure 3) with the open ends 24 leading, is derived from wave motion via a converter 30.

The pressurised air discharged into the chamber 26 from the ends 25 of the four coils 21 is conveyed via a pipe 31 from the chamber 26 to a turbine-driven dynamo 32 to generate electrical power. The water collected under pressure in the chamber 26 may also be put to useful purpose, via a pipe 33.

A system for pumping air and water under wave, and also tide, movement, is illustrated in Figure 5, and will now be described.

Referring to Figure 5, the rotor 20 is given buoyancy to float in the sea with its rotational axis 27 generally horizontal. A tether arm 31 anchors the rotor 20 but allows it to float up and down along the arm 31 with wave and tide motion. More particularly, the coupling of the rotor 20 to the tether arm 31 is through a gear mechanism (not shown) of the rotor 20 that converts these movements into incremental turning of the rotor 21 unidirectionally about the axis 27.

Drive for the rotor 20 is also provided through the gear mechanism from the angular movements about the axis 27 of two floats 32. The floats 32 are mounted on respective arms 33 that extend from the rotor 20 so as to pivot up and down about the axis 27 individually according to the wave motion. These pivotal movements are converted via the gear mechanism into unidirectional turning increments of the rotor 20.

As the rotor 20 is turned, so the pressurised air and water collected in the chamber 26 is supplied via a pipe 34 downwardly under the water to collect the air in a submerged air duct 35. From the duct 35 the air may be supplied to impulse a turbine wheel of the Pelton form that rotates in the water, the air being discharged, for example, from below into the buckets of the wheel to give, through the impact and buoyancy thereby afforded to the rising buckets, a turning moment on the wheel. The pressurised water supplied by the pump can be used in a similar manner, for example to impact the buckets on their descent and give a cumulative turning moment with that provided by the air.

The constancy of pressure output of the pump depends on the number of coils used and the speed of rotation.

Where rotation is slow, and perhaps, incremental, advantage may be gained in using a larger number of coils. Furthermore, it has been found that there is advantage in making the open, outer ends of the coils of enlarged diameter to facilitate admission of the water and air to the spiral passageway. A modification that is applicable in this respect in the provision of the open end 4 of pump of Figures 1 and 2 and of the individual open ends 24 of the pump of Figures 3 to 5, is illustrated in Figure 6.

Referring to Figure 6, the open end 44 of the spiral passageway in this case is provided by an end-fitting 45 that consists of tubing having a larger diameter than the tubing 46 of the remainder of the coil. The fitting 45 is of a length comparable with the portion of the circumference of the rotor that is at any time submerged in the water, so that throughout this initial length of the spiral passageway, the cross-sectional area is enlarged. A bleed hole 47 is provided in the fitting 45 so as to facilitate rapid filling with water as the open end 44 moves into the water.

Although the pump of the invention has been described above in the context of providing increase in pressure, it has possible application in pressure reduction. In this respect, where the open end of the spiral passageway is at the inner end of the spiral, the progressive radial-translation of the quantities of fluid, water and air in the cases described, is outward during rotation rather than inward. The volume of the air is thus caused to increase as rotation continues, resulting in a progressive pressure reduction. Thus, the air and water are discharged from the outer end at reduced pressure.

Claims

Claims:

1. A pump having a rotor which is for rotation through the interface between bodies of two different fluids and which involves an elongate passageway for containment of quantities of both fluids, wherein the passageway extends spirally radially of the rotor with a cross-sectional area that decreases or is substantially constant inwardly of the spiral, and the passageway is open at one end to admit quantities of fluid from one body and then the other in turn as the rotor rotates through the interface such that with continued rotation of the rotor the successively-admitted quantities of the two fluids are translated radially with respect to the rotor for discharge from the other end of the passageway.

2. A pump according to Claim 1 wherein the passageway is formed by tubing that is wound upon itself.

3. A pump according to Claim 2 wherein the tubing is wound on a spool or reel of the rotor, and the spool or reel has flanges for constraining the tubing to retain it in the spirally-wound configuration.

4. A pump according to any one of Claims 1 to 3 wherein the open end of the passageway is the radially outermost end.

5. A pump according to Claim 4 wherein said other end of the passageway vents into a chamber which is located on the rotational axis of the rotor for separation of the fluids from one another therein.

6. A pump according to Claim 4 or Claim 5 wherein it is arranged that fluid discharged from said other end of the passageway is supplied to drive a turbine.

7. A pump according to any one of Claims 4 to 6 wherein an initial length of the passageway at the open end is of enlarged cross-sectional area as compared with the remainder.

8. A pump according to Claim 7 wherein said initial length of the passageway incorporates means for bleeding air therefrom during rotation of the rotor.

9. A pump according to any one of Claims 1 to 8 including a plurality of said passageways and wherein the open ends of the respective passageways are spaced angularly from one another about the rotational axis of the rotor.

10. A pump according to any one of Claims 1 to 9 wherein the rotor is arranged to be rotated by wave or tide movement, wind power, or water flow, or a combination of two or more of these.

11. A method of pumping wherein a rotor which involves an elongate passageway that extends spirally radially of the rotor with a cross-sectional area that decreases or is substantially constant inwardly of the spiral, and is open at one end, is rotated through a substantially horizontal interface between bodies of two different fluids such that successive quantities of fluid from one body and then the dther in turn are admitted to the passageway through the open end and are translated radially of the rotor for discharge from the other end of the passageway.

12. A method of pumping according to Claim 11 using a pump according to any one of Claims 2 to 9.

13. A method of pumping according to Claim 11 or Claim 12 wherein the fluids are water and air.

14. A method of pumping according to any one of Claims 11 to 13 wherein the rotor is rotated by wave or tide movement, wind power, or water flow, or a combination of two or more of these.

15. A pump substantially as hereinbefore described with reference to Figures 1 and 2, or Figure 3.

16. A pump according to Claim 15 as modified substantially as hereinbefore described with reference to Figure 6.

17. A pump installation substantially as hereinbefore described with reference to Figure 4 or Figure 5.

18. A method of pumping substantially as hereinbefore described with reference to Figures 1 and 2, or Figure 3, or Figure 4, or Figure 5.