The present disclosure relates to fluid machines. Some embodiments provide fluid machines usable as pumps or turbines in various applications.
Various solutions exist for fluid machines for applications such as pumps, e.g. for pumping of live fish in fish farming; turbines, e.g. turbines for use in micro- and mini power plants in rivers, streams or ocean currents; thrusters for maneuvering and propulsion of ships; fans; blowers or similar applications.
Publications which may be useful to understand the background include US 2005/0284394 A1; GB 1172179 A; GB 2042641 A; CN 201943973 U; and WO 91/18501 A1.
There is nevertheless a need for improved technology in relation to fluid machinery in general, and to fluid machines for particular, specialist applications. The present invention has the objective to provide fluid machines which provide advantages or alternatives to known solutions.
In an embodiment, there is provided a fluid machine having an intake part, a discharge part, and an impeller, the impeller being arranged in an enclosure, and a transmission arranged in the enclosure and operationally connecting a rim of the impeller with an energy converter.
Further embodiments are described in the appended claims and in the detailed description below.
These and other characteristics will become clear from the following description of illustrative embodiments, given as non-restrictive examples, with reference to the attached drawings, in which
The following description may use terms such as “horizontal”, “vertical”, “lateral”, “back and forth”, “up and down”, “upper”, “lower”, “inner”, “outer”, “forward”, “rear”, etc. These terms generally refer to the views and orientations as shown in the drawings and that are associated with a normal use of the invention. The terms are used for the reader's convenience only and shall not be limiting.
In one embodiment,
Referring to
An impeller 24 is arranged in the enclosure 18, and a driveline 90 is also arranged in the enclosure 18 and operationally connecting a rim 11 of the impeller 24 with a prime mover 2. Operating the prime mover 2 thus causes a rotation of the impeller 24. In this embodiment, the driveline 90 is a belt drive. As most clearly illustrated in
Also shown in
The impeller 24 may for this purpose have integrated surfaces for the drive belt 12 arranged on its outer perimeter/rim 11. Alternatively, the driveline 90 may be a chain drive, or any other suitable transmission operating on the rim 11 of the impeller 24. Alternatively, the driveline 90 may be a gear drive, for example by means of a first gear arranged on the shaft 2a of the prime mover 2 engaging a toothed outer surface of the rim 11 (i.e. such that the impeller 24 acts as a second gear in the driveline 90). The relative size of the sheave 10 (or equivalent gear, if using a gear transmission) to the rim 11 outer diameter can be designed such as to obtain desired operating speeds of the system components.
In the embodiment illustrated in
The prime mover 1 is in this embodiment an electric motor, but may in any of the embodiments described herein be, for example, a hydraulic motor, a pneumatic motor, or any other machine operable to deliver rotary power. The prime mover 1 is located outside the enclosure 18, and a shaft bearing 15 and shaft seal 16 are arranged to support and seal against the shaft of the prime mover 1 extending into the enclosure 18 and to the sheave 10. The shaft seal 16 may, for example, be a labyrinth seal, a lip seal or a face seal around the shaft 2a of the prime mover 2. The shaft seal 16 may thus isolate the prime mover 2 from any fluid inside the enclosure 18.
A labyrinth seal 17 (or a different type of seal or constriction) may be arranged at the impeller rim 11 to partly or fully isolate the interior of the enclosure 18 from the process fluid flowing through the fluid machine 1. This may help reduce pollution of the bearings 14c and the driveline 90. The constriction or labyrinth seal 17 thus prevents particles, debris or other undesired elements from reaching the engagement surfaces of the bearings 14c and/or the components of the driveline 90. The constriction or labyrinth seal 17 may thus at least partially separate the interior of the enclosure 18 from the annular volume 31.
The impeller 24 in this embodiment has an open centre section and is arranged in an annular volume 31 (see
When operating the prime mover 14, a fluid flow is thus generated through the fluid machine 1, whereby an intake flow 30 is separated in a first flow 30b through the annular volume 31, and a second flow 30a through the duct 23. In the annular volume 31, the impeller 24 accelerates the first fluid flow 30b. Downstream the annular nozzle 32, the high-velocity fluid flow 30b from the annular volume 31 creates a pressure reduction at the throat section 33 (a “suction effect”), thereby generating the first fluid flow 30a through the duct 23. The duct 23 thus provides a restriction-free passage for fish or other non-fluid elements via fluid flow 30a.
The first and second fluid flows 30a,b are joined in a diffuser section 34, whereby a uniform outlet flow 38 is created in the discharge pipe 27.
A grid 22 (see
As can be seen in
In one embodiment, the fluid machine 1 according to the embodiment illustrated in
For example, the injection nozzle 19 may be used to inject a cleaning agent into the enclosure 18 such as to clean the components therein and the interior surfaces. In a fish pump application, this may for example be part of periodic cleaning of the equipment. In other applications, such as in a thruster drive, the fluid may be one which prevents marine growth. In yet other applications, it may be desirable to inject a gas, steam and/or fluids which provide for example rust inhibition, lubrication or surface treatment of the components in the enclosure 18.
In some embodiments, the injection nozzle 19 can be used during operation of the fluid machine 1, either periodically or continuously or semi-continuously. In some embodiments, the enclosure 18 may, in conjunction with the seal 17 and/or the shaft seal 16, allow the fluids to remain within the enclosure 18 for a prolonged period of time, whereby such fluids can provide an effect over longer time and the need for continuous or repeated injections is reduced. This may for example in a fish pump application relate to fluids to prevent bacterial growth in the enclosure 18.
In another embodiment, illustrated in
In this embodiment, the intake flow 30 enters the duct 23 directly when the fluid machine 1 is submerged in a liquid (and not via an intake pipe, as in the embodiments described above). A first flow 30b flows through the annular volume 31, where it is accelerated by the impeller 24, and a second flow 30a flows through the duct 23. The outlet flow 38 flows to the discharge pipe 27.
As above, a grid 22 (which may be a combined grid and guide vanes) can provided at the intake part 21 of the enclosure to prevent larger items (such as fish or debris) to enter the annular volume 31.
A suspension element 9, such as a hook receiver or a shackle, is provided to suspend or hang the fluid machine off, for example, a crane.
The discharge pipe 27 in this embodiment may be a flexible pipe, whereby the fluid machine 1 can be moved to the desired position substantially freely.
In this embodiment, the prime mover 2 may be enclosed in a sealed housing 29, such as to allow the entire fluid machine 1 to be submerged in the liquid to be pumped. Power and control signals to the prime mover 1 may then be provided through the sealed housing 29 via a water-tight extension through a wall of the sealed housing 29.
All other features described in relation to the embodiments shown in
In this embodiment, the requirements for the enclosure 18 to be fully water-tight may be relaxed, which eases the design of the unit and reduces the risk of operational downtime.
In some embodiments, for example the embodiment illustrated in
The injection nozzle 28 may be utilised to inject, for example, oxygen or pharmaceutical agents into the process fluid. Positioning the injection nozzle 28 downstream the impeller 24 at the annular nozzle 32, throat section 33 or diffuser section 34 may ensure a thorough mixing into the entire fluid volume through the mixing of the first and second fluid flows which naturally occur in the throat and diffuser sections of the discharge part. The positioning of the injection nozzle 28 may thus be chosen to obtain optimal mixing, for example by means of fluid dynamics simulations or testing. Additionally or alternatively, injection of air or a gas into the annular jet may be used to directly modify the flow properties of the annular jet flow for example when it enters the throat and diffuser sections of the discharge part, in order to obtain a desirable flow field out of the fluid machine 1.
In the embodiment shown in
In order to accommodate a greater distance between the impeller/propeller 24 and the prime mover 2, the belt layout is slightly different (a longer drive belt may be used), but otherwise the main operating principles may the same as those described in relation to the embodiments described above. In this embodiment, the combination of nozzle 52 and the neck/steering column 56 make up the watertight enclosure (item 18 in the other embodiments). The entire thruster can azimuth (i.e. rotate) about the central axis of neck/steering column 56. (The actuating mechanism and bearings for the azimuth function are not shown here, as these are well known components.)
In this embodiment, the fluid machine 1 may operate as a thruster for the vessel 80 when in the first position, but may be retracted when not in use, such as to reduce hydrodynamic drag for the vessel 80. The centreboard 55 may be arranged in a sealed trunk 53 or the like in the hull of the vessel 80, which forms an enclosure for the impeller/propeller 24 and associated components similarly as above. The second position may be such that the centreboard 55 is below or partially below a waterline 81 when in the second position.
In one embodiment, the centreboard 55 has an additional third position, in which the centreboard 55 can be moved further into the hull of the vessel 80. The third position is illustrated in
The fluid machine 1 may have flow guide elements, such as an upstream bulb 63 with guide vanes 62 to provide an advantageous flow field towards the impeller 24. The impeller 24 may be open-centred or not open-centred. A downstream bulb 65 with outlet guide vanes 64 may also be arranged downstream the impeller 24 to optimise performance.
The fluid machine 1 may otherwise be of the same design and comprise any of the individual features shown in relation to the embodiments described above, or any combination of such features. The driveline between the impeller 24 and the generator 2′, although in this embodiment operable to generate power from the fluid, may be arranged in the same manner.
The enclosure 18 has a fluid inlet opening 18a connected to an inlet pipe 20 and a fluid outlet opening 18b connected to an outlet pipe 27. The impeller 24 is arranged on a support frame 42a arranged within the enclosure 18, and the support frame 42a is movable between a first position in which the impeller 24 is positioned between the inlet opening 18a and outlet opening 18b, i.e. aligned with the pipes 20,27 in a flow path defined by the inlet and outlet pipes 20,27, and a second position in which the impeller 24 is spaced from the flow path.
In this embodiment, the support frame 42a is connected to the enclosure 18 via a pivot bearing 41, and the support frame 42a is pivotable about an axis which extends through the pivot bearing 41. The axis may coincide with a central axis of the output shaft of the prime mover 2 or generator 2′. This may allow the prime mover 2 or generator 2′ to be spatially fixed in relation to the pipes 20,27 and other components, i.e. that the prime mover 2 or generator 2′ need not move with the support frame 42a. However the fluid machine may, alternatively, be arranged such that the prime mover 2 or generator 2′ moves with the support frame 42a.
While this embodiment shows a pivoting movement of the support frame 42a, it may alternatively be movable between the first and second positions in a different manner, for example by linear displacement.
Alternatively, the second part of the support frame 42b may have a closed wall, such as to block the flow path between the pipes 20,27 when the support frame 42b is in the second position. In these embodiments, it is thereby possible to change the operational setting of the fluid machine 1 according to operational needs. For example, the bypass aperture 43 can be positioned between the pipes 20,27 to allow free flow of fluids through the pipes 20,27, or the closed wall can be positioned between the pipes 20,27 to prevent fluid flow.
The support frame 42b may be manually movable between the first and second positions by an operator, or it may comprise an actuator for driving the support frame 42b between the positions.
In some embodiments, other components of the system may also be fixed to the support frame 42a,b such as to be movable together with the support frame 42a,b. This may include, for example, the duct 23 in the pump application described in relation to
In one embodiment, the fluid machine 1 further comprises a seal system 44 arranged to isolate the interior of the enclosure 18 when in the second position. The seal system 44 may for this purpose seal between the intake and discharge pipes 20,27 and a face on the second part of the support frame 42b when in the second position. The seal system 44 may, for example, comprise seals arranged circumferentially around the end faces of the pipes 20,27. By means of the seal system 44, fluid in the pipes 20,27 can be prevented from flowing into the enclosure 18 when the support frame 42b is in the second position. This allows the enclosure 18 to be drained, and for example cleaning, inspection, maintenance or repairs to be carried out on the impeller, drive line or other components.
Direct access to the impeller 24 and associated components within the enclosure 18 may thus be possible without dismantling the entire enclosure 18 or the pipe system, for example via a hatch or a service door in the enclosure 18. In embodiments with a bypass aperture 43, the pipe system can continue to be operational during for example maintenance and operational downtime of the overall plant can be avoided. For example, if several fluid machines 1 are arranged in series, one fluid machine 1 may be subject to inspection or maintenance, while the others are still operational on the fluid flowing through the pipes 20,27.
Alternatively, or additionally, to that described above, the fluid machine 1 may be arranged such that the impeller 24 in the second position is positioned higher than the pipes 20,27. This may allow such access to the internal components in the enclosure 18 to be carried out with less risk of leakage, and less demands on the seal system 44. Depending on the fluid pressure in the pipes 20,27, this may in certain embodiments allow the enclosure 18 to be opened without a seal system 44. For example, if non-pressurized liquid stands in the pipes 20,27, the enclosure 18 may still be opened and accessed without draining down the pipes 20,27 entirely.
In a fish pump application, such as that illustrated in
In a tunnel thruster application, such as that illustrated in
Although the above illustrative embodiments are described with a view to operation in sea- or freshwater, it is to be understood that the invention is not limited to applications in water, as other process fluids may be of interest in other applications or markets.
In any of the embodiments described herein, the prime mover 2 or generator 2′ may be located in air (or an inert gas), and the driveline 90 and related components located inside the waterproof enclosure 18 submerged in a fluid. This may relax the need for a waterproof rating of the prime mover 2 or generator 2′, which may for example enable the use of low cost, standard machines. Having a waterproof enclosure 18 around the driveline 90 and associated components may allow the use of a simple, off-the-shelf shaft seal for the prime mover 2 or generator 2′, and avoid large-diameter, customized solutions for example for sealing around the impeller 24.
In any of the embodiments described herein, the prime mover 2 or generator 2′ may be located inside a watertight enclosure 29. This may allow the use of low cost, standard machines without waterproof rating also in applications where the entire machine is submerged, such as for example the embodiment shown in
In any of the embodiments described herein, the impeller 24 may be an open centre impeller. An open centre impeller may be an advantage in various applications, such as in a fluid pump for live fish or in a thruster for a vessel, where an open centre impeller/propeller may allow debris such as ropes, nets, etc. to pass through the impeller with less risk of entanglement and damage to the thruster.
In any of the embodiments described herein, the fluid machine 1 may be configured to handle a process fluid, and the bearings 14c may be configured to operate submerged in the process fluid. They bearings 14c may additionally be lubricated by the process fluid. The process fluid may, for example, be water.
In any of the embodiments described herein, the driveline 90 may be configured for operation submerged in the process fluid.
In any of the embodiments described herein, the prime mover 2 or the generator 2′ may be arranged vertically higher than, and optionally vertically above, the impeller 24. This may reduce the sealing requirements for the enclosure 18, particularly for the shaft seal between the prime mover 2/generator 2′ and the sheave 10. In some embodiments, for example if using a belt drive 12, this arrangement further allows the belt tension to partially carry and centre the mass of the impeller 24, and thereby reduce the load on the bearings.
In any of the embodiments described herein, the prime mover 2 or generator 2′, as well as the driveline 90, may be fixed to the enclosure 18 or may be carried by a dedicated support structure within the enclosure 18. This allows the enclosure 18 to provide structural support for these and associated components.
If large lifting heights or high flow volumes are required, several fluid machines according to any of the embodiments described herein can be operated in series.
In any of the embodiments described herein, the discharge pipe 27 can have an increasing cross-sectional area downstream the annular nozzle 32 (see e.g.
The duct 23 may have a cylindrical shape, having a constant cross-sectional area along its longitudinal extension. Fluid openings to the annular volume 31 may be provided as radial openings in the cylindrical duct. A cylindrically shaped duct 23 may ease manufacturing and assembly of the fluid machine.
The teaching herein thus provides fluid machines with simplified production and/or maintenance, with relaxed requirements for specialist skills for their manufacture, operation, maintenance and/or repairs. For example, if a belt drive transmission is used, a fault-tolerant system can be obtained, which is less sensitive to alignment errors. Additionally, or alternatively, embodiments which use standard electric or hydraulic motors may reduce cost and ensure highly reliable operation.
Some embodiments may provide solutions which reduce the risk of damage to the fluid machine itself, and/or to items being pumped, such as fish.
Some embodiments provide flexibility to design a compact machine with reduced requirements for external equipment or piping.
As will be appreciated when reading the disclosure, the principles described herein may be applicable to a wide range of applications and the invention is not limited to the embodiments described herein. Other applications may, for example, be a pump for pumping fluids comprising solids that may damage the impeller blades if coming into contact with them, or fluids comprising other elements which may, like fish, themselves be damaged if they come into contact with the impeller blades. For example, pumps for stripping (i.e. emptying) of ballast water or liquid cargo tanks in ships or removal of flood water which may contain debris are other examples of potentially suitable applications.
Number | Date | Country | Kind |
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20180926 | Jun 2018 | NO | national |
Filing Document | Filing Date | Country | Kind |
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PCT/NO2019/050118 | 6/11/2019 | WO | 00 |