GB2318154A - Turbine-driven fluid impelling apparatus - Google Patents

Abstract

Apparatus for propelling fluid from a fluid inlet 3 to a fluid outlet 5 by a propeller 18, for moving seabed material. The propeller 18 is driven by high pressure water, directed by a plurality of discharges 14, which act against a rotor comprising a series of blades (24) forming an annular ring 22. The apparatus may also be used to propel floating, submerged or airborne vehicles or objects.

Description

"Apparatus for Propelling Fluid" This invention relates to an apparatus for propelling fluid, and particularly, but not exclusively, to apparatus for underwater excavation, or to apparatus for the propulsion of a floating, submerged or airborne vehicle or object.

Conventionally, in order to excavate seabed material underwater, it is known to use a driven propeller to propel water from above the propeller to below the propeller, thus creating a blast of water which moves the seabed material. In order to power the propeller, it is known to pump relatively high pressure water into a drive mechanism which is mounted to the tips of the propeller. The drive mechanism may consist of nozzles opening approximately tangentially in the reverse direction with respect to the required rotation of the propeller, so that the reaction thrust of the issuing jets of water produces a torque to cause the propeller to rotate. This conventional drive mechanism has the disadvantage that energy is wastefully carried by the issuing jets of water.

An alternative known drive mechanism consists of hinged vanes that, when open, form a piston within a circumferential chamber that encloses the drive mechanism. The high pressure water acts against the open vanes and accordingly rotates the drive mechanism.

The water leading the open vanes exits the drive mechanism through ports which precede a restriction in the circumferential chamber which forces the vanes to close. When the vanes clear the restriction in the circumferential chamber, they are permitted to open and once more form a piston for the introduction of the high pressure water.

This conventional apparatus has a disadvantage that the movable vanes may be subject to relatively high levels of mechanical failure.

According to the present invention there is provided apparatus for propelling fluid comprising a fluid inlet and a fluid outlet, a propeller mounted between the fluid inlet and the fluid outlet for propelling fluid from the fluid inlet through the fluid outlet, a rotor driving the propeller, and at least one discharge for a driving fluid arranged such that driving fluid ejected at pressure from the driving fluid discharge rotates the rotor.

Preferably, the driving fluid ejected from the discharge acts against one or more blades on the rotor.

Preferably, the plane on which the propeller is located is perpendicular to the flow of the propelled fluid.

Preferably, the rotor is located at the periphery of the propeller. More preferably, the blades are located in a plane parallel to the rotational plane of the propeller, and most preferably, said planes are coincident.

Preferably, there are a plurality of discharges for discharging the driving fluid.

Preferably, the rotor blades offer a curved path of travel to the driving fluid, and more preferably, the blades are crescent shaped.

Typically, the driving fluid discharge comprises a fluid directing device which alters the direction of flow of the driving fluid entering it from a first direction, which is substantially perpendicular to the plane on which the blades are located, to a second direction, which is at an angle to the plane on which the blades are located.

The rotor blades may be in the form of turbine blades.

The driving fluid and the propelled fluid may be the same substance, and will typically be seawater.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: Fig. 1 shows a side view of an apparatus for propelling fluid; Fig. 2 shows a plan view of the apparatus of Fig.l; and Fig. 3 shows a cross sectional view of a driving station of the apparatus of Figs. 1 and 2.

Fig. 1 shows an apparatus 1 for propelling fluid where the fluid will be water for underwater applications.

The apparatus 1 comprises a rotor and a stator, where the stator includes a hollow cylinder 10, and a connection pipe 12 for connection of the apparatus 1 to a vessel (not shown) at the water surface. The hollow cylinder 10 is coupled to the bottom end of the connection pipe 12. Driving stations 14 are coupled to the inner surface of the hollow cylinder 10. Water conduits 16 convey high pressure water from the vessel at the water surface to the driving stations 14.

Alternatively, the high pressure water may be conveyed down the bore of the connection pipe 12, and fed into the water conduits 16 at an appropriate junction on the connection pipe 12.

The rotor includes a propeller 18 which is coupled to a propeller shaft 20 which is freely rotatably coupled to the connection pipe 12. An annular ring 22 is connected to the outer periphery of the propeller 18.

Fig. 2 shows, in particular, the annular ring 22 in plan view. The annular ring 22 comprises a plurality of turbine blades 24 which extend radially from an inner wall 26 to an outer wall 28 of the annular ring 22 and are equi-spaced around the annular ring 22.

In Fig. 2, four propeller oars 30 are shown and three driving stations 14 are also shown (a fourth driving station 14 is omitted to show the connection 32 between one of the propeller oars 30 and the annular ring 22).

The water conduits 16, which are shown in Fig. 1, connect to the driving stations 14 at the driving station inlets 34.

Fig. 3 shows the spatial relationship and configuration between the driving station 14 of the stator, the turbine blades 24 and the annular ring 22 of the rotor.

In operation, high pressure water is conveyed from the water conduits 16 (not shown in Fig. 3) into the driving station inlet 34, in the direction of arrow 36.

In order to increase the efficiency of the apparatus 1, stator blades 38 and an inner surface 40 of the driving station 14 in the path of the high pressure water, are formed to alter the flow direction and the flow characteristic of the high pressure water. The change of flow direction of the high pressure water caused by the stator blades 38 and the inner surface 40 of the driving station 14 is shown by arrow 42. As the water exits the driving station 14, the flow direction is at an angle compared to that of the water entering the driving station inlet 34, as indicated by arrow 36.

The water discharged by the driving station 14 acts against the turbine blades 24 of the rotor, causing the turbine blades 24 and thus the rotor to rotate in the direction of the arrow 44. In order to increase the efficiency of the apparatus 1, the turbine blades 24 are crescent-shaped in cross-section. The direction of the water as it passes through the crescent-shaped turbine blades 24 is shown by arrow 46, and as the water exits the crescent-shaped turbine blades 24, the water is moving in a relatively opposite direction with respect to the intended rotational direction of the rotor in the direction of arrow 44. Therefore when the rotor is rotating at its intended operational speed, the net tangential velocity of the issuing water relative to the rotational direction of the rotor is made small by the appropriate shape of the rotor blades 24. This ensures that the issuing water wastefully carries with it only a minimum amount of energy.

Therefore, as the high pressure water travels through the driving stations 14 then consequently through crescent-shaped turbine blades 24 the propeller 18 is rotated.

As the propeller 18 rotates, water adjacent the inlet 3 of the apparatus 1 is pulled through the inlet 3 by the propeller 18 in the direction of arrows 2, and is forced out through an outlet 5 in the hollow cylinder 10 in the direction of arrow 4. Accordingly, if the flow of water from the outlet 5 of the apparatus 1 is directed at seabed material 6, then the seabed material 6 will be excavated.

The production of the flow of water through apparatus 1 necessarily results in the development of a reaction thrust in the axial direction of propeller 18. The apparatus 1 may therefore alternatively be used as a means of propulsion for any floating, submerged or airborne vehicle or object to which it is attached.

Modifications and improvements may be made to the foregoing without departing from the scope of the present invention.

Claims (14)

1. Apparatus for propelling fluid comprising a fluid inlet and a fluid outlet, a propeller mounted between the fluid inlet and the fluid outlet for propelling fluid from the fluid inlet through the fluid outlet, a rotor driving the propeller, and at least one discharge for a driving fluid arranged such that driving fluid ejected at pressure from the driving fluid discharge rotates the rotor.

2. Apparatus as claimed in claim 1, wherein the plane on which the propeller is located is perpendicular to the flow of the propelled fluid.

3. Apparatus as claimed in claim 1 or claim 2, wherein the rotor is located at the periphery of the propeller.

4. Apparatus as claimed in any preceding claim, wherein the driving fluid ejected from the discharge acts against one or more blades on the rotor.

5. Apparatus as claimed in any preceding claim, wherein the blades of the rotor are located in a plane parallel to the rotational plane of the propeller.

6. Apparatus as claimed in claim 5, wherein the two planes are coincident.

7. Apparatus as claimed in any preceding claim, wherein the rotor blades define a curved path of travel for the driving fluid.

8. Apparatus according to any one of claims 4 to 7, wherein the blades are crescent-shaped.

9. Apparatus as claimed in any preceding claim, wherein there are a plurality of discharges for ejecting the driving fluid.

10. Apparatus as claimed in any one of claims 4 to 9, wherein the driving fluid discharge comprises a fluid-directing device which alters the direction of flow of the driving fluid entering it from a first direction, which is substantially perpendicular to the plane on which the rotor blades are located, to a second direction, which is at an angle to the plane on which the rotor blades are located.

11. Apparatus as claimed in any one of claims 4 to 10 wherein the rotor blades are turbine blades.

12. Apparatus as claimed in any preceding claim, wherein the driving fluid and the propelled fluid are the same substance.

13. Apparatus as claimed in claim 12 wherein the driving fluid is seawater.

14. Apparatus substantially as hereinbefore described with reference to any one of the accompanying drawings.