The present invention relates generally to pipes useful for harnessing hydrokinetic energy. More particularly, the present invention relates to novel designs and assembly methods for pipes, which allow for easy inspection and installation of turbines useful for harnessing hydrokinetic energy.
Hydrokinetic energy refers to the generation of energy from the flow, current or velocity of water. This type of energy is different from hydroenergy, which traditionally refers to power generated using dams (impoundment or run-of-river). Since hydrokinetic energy relies on the velocity of water, these energy systems can be placed into sources of flowing water with minimal infrastructure or environmental impacts. As a result, hydrokinetic power is considered cutting-edge waterpower.
To harness hydrokinetic energy, typically turbines operate in rivers, oceans and tidal settings. By way of example, in rivers, turbines can be installed for applications that harness energy from such settings as in-stream, free-flow, open-river or hydrokinetic run-of-river. As other examples, in ocean and tidal settings, turbines harness ocean power and tidal power, respectively.
These turbines may be loaded onto a barge, which is well equipped with cranes to facilitate the raising and lowering of individual turbines and power generating units that accompany them. In other examples, these turbines may be integrated into an in-pipe hydro-electric power generator.
Unfortunately, whether a barge or an in-pipe hydro-electric power generator is used, the current designs and methods of harnessing hydrokinetic energy suffer from drawbacks. By way of example, during operation, the turbine typically undergoes fouling and clogging by bio-growth, debris, sediment, and ice that is dragged by the flowing water. As expected, this results in reduced flow through the turbine, increased head losses and hydrostatic forces. To prevent or minimize such undesired consequences maintenance of the turbine is periodically conducted. The frequency of maintenance depends on, among other things, the amount of fouling and clogging agents present in the water flowing through the turbine. Regardless of the number of times maintenance is carried out, each time maintenance is deemed necessary, a significantly heavy turbine, i.e., typically weighing between about 0.5 tons and about 10 tons, is lifted up and removed from the water flow path. In most instances, the turbine is transported to a maintenance facility. Maintenance, therefore, not only represents a time-consuming and arduous task, but also requires extensive equipment (e.g., cranes and trailers). Furthermore, it is important to be very careful when moving such heavy equipment that the pipe or some portion of the turbine is not damaged because repair or permanent damage translates into additional costs.
What are therefore needed are designs and assembly methods for pipes, which allow for easy inspection and maintenance of turbines useful for harnessing hydrokinetic energy.
In view of the foregoing, this invention provides designs and assembly methods for pipes, which allow for easy inspection and maintenance of turbines useful for harnessing hydrokinetic energy.
In one aspect, the present invention provides a conduit. The conduit includes a cylindrical body having defined therein a first aperture and a second aperture, wherein the first aperture is designed to receive a shaft of a turbine and the second aperture is sufficiently large to facilitate ingress or egress of a probe through the second aperture, and wherein the second aperture is located a distance away from the first aperture such that when the shaft of the turbine is disposed through the first aperture, an entry by a probe into the cylindrical body through the second aperture is not prevented by presence of the turbine. The second aperture is defined by an opening in a cylindrical body perpendicularly disposed on the conduit and protruding outward and the opening is a flanged opening. Inventive conduits of the present invention may further include a generator and a coupling, wherein the coupling serves as an interface between the shaft of the turbine and a shaft of the generator.
In accordance with one embodiment of the present invention, the first aperture has a diameter that is between about 2 inches feet and about 6 inches. In preferred embodiments of the present invention, however, the diameter is between about 2 inches and about 4 inches. Similarly, in one embodiment of the present invention, the second aperture has a diameter that is between about 2 feet and about 3.5 feet, but preferably has a diameter that is between about 2.5 feet and about 3.5 feet. The distance between the first aperture and the second aperture may be between about 2 feet and about 60 feet, but is preferably between about 4 feet and about 10 feet. The cylindrical body may have a diameter that is between about 2.5 feet and about 10 feet.
The turbine may be any one of spherical turbine, helical turbine, troposkein turbine, and circular-, square- or rectangular-shaped turbine. The probe may be a human, a motor-driven object or a remotely controlled object. In preferred embodiments, inventive conduits further include a frame assembly that is mounted on the conduit and disposed above the first aperture, and the frame assembly is designed to secure a generator above the turbine when the turbine is disposed through the first aperture. In certain preferred embodiments, the inventive conduits include a cover which covers the second aperture. The first aperture may be located upstream from the second aperture, but is preferably located located downstream from the second aperture.
In one embodiment of the present invention, inventive conduits include a first block, a first seal, and a first bearing that are disposed near first aperture to secure the turbine at a first location that is adjacent the first aperture. In certain embodiments of the present invention, inventive conduits also include a third aperture disposed opposite to the first aperture such that the shaft of the turbine passes through both the first aperture and the third aperture. Inventive conduits may further include a second seal, a second bearing and a second block to secure the turbine at a second location that is adjacent the third aperture.
In another aspect, the present invention provides a method of assembling a conduit capable of generating power. The method includes: (1) obtaining a cylindrical body having defined therein a first aperture and a second aperture; (2) introducing a turbine through the second aperture; and (3) displacing the turbine inside the conduit towards the first aperture such that a central axis of the turbine, which is capable of receiving a shaft, aligns with the first aperture.
In accordance with one embodiment of the present invention, in the above-mentioned step of obtaining, the second aperture is located on the cylindrical body a distance away from the first aperture such that an entry by a probe into the cylindrical body through the second aperture is not prevented by presence of the turbine.
Inventive methods may further include a step of covering the second aperture with a cover (e.g., blind flange). Furthermore, the step of introducing may include disposing a turbine that is any one of spherical turbine, helical turbine, troposkein turbine, and circular-, square- or rectangular-shaped turbine.
In preferred embodiments, inventive methods further include installing a frame assembly that is mounted on the conduit and disposed above the first aperture. This embodiment may further still include securing a generator using the frame assembly above the turbine.
The cylindrical body, implemented in the inventive methods, may have defined therein a third aperture and preferred embodiments of the inventive methods may include: (1) passing the shaft of the turbine through the first aperture and the third aperture; and (2) securing the shaft of the turbine near the first and the third apertures to prevent substantial lateral displacement of the turbine.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following descriptions of specific embodiments when read in connection with the accompanying figures.
In the following description numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without limitation to some or all of these specific details. In other instances, well known process steps have not been described in detail in order to not unnecessarily obscure the invention.
First aperture 104 may have a diameter large enough to receive a shaft of a turbine, which is ultimately inside conduit 50, as explained with respect to
In accordance with one preferred embodiment of the present invention,
A coupling 114 disposed above bearing 126 serves as an interface between shaft 118 of turbine 108 and generator shaft (not shown to simplify illustration) of a generator 110. A generator frame 112 is attached to conduit 102 using a mounting bracket 124 and serves to secure generator 110 to conduit 102. On conduit 102, adjacent to generator 110 and generator frame 112, disposed is a substantially cylindrically-shaped body 138 that protrudes outwardly from second aperture (which is shown in
Although first, second and third apertures are not shown in
Generator 110 can be any generator that is designed to work in connection with a turbine to produce power. However, in preferred embodiments of the present invention, generator is a permanent magnet three-phase generator. Coupling 114 and blocks 140 and 130 are made from a rigid material, which is preferably made from a material that facilitates a formation of a welded connection to conduit 102. By way of example, in such preferred embodiments of the present invention, coupling consists primarily of intermeshing parts, such as two steel hubs with a more flexible component disposed between them which is capable of flexing slightly in order to compensate for shaft misalignment and transfer torque. Blocks 140 and 130 are preferably made from metal (e.g., steel).
Seals 134 and 136 are made from any material that effectively seals off high pressures encountered at the bottom of third aperture and top of first aperture, respectively. In preferred embodiments of the present invention, these seals are made from either cartridge-type face seal assemblies or radial lip seal assemblies. Bearings 126 and 132 are made from any material that reduces frictional forces acting on shaft 118 when it is rotating. Preferably, however, bearings 126 and 132 are made from a flanged spherical roller bearing assembly.
The present invention also provides a method of assembling an in-conduit hydroelectric power generator 100 shown in
Although the present invention contemplates introducing a turbine (e.g., turbine 108 as shown in
In one preferred embodiment, the inventive processes include covering the second aperture with a cover. By way of example, the cover is a blind flange that is bolted on to 116 to seal it. During installation, the cover is removed to provide a point of entry inside the conduit as described above Similarly, during an onsite inspection, the same cover is removed to provide access to a probe to inspect the turbine (e.g., spherical turbine, helical turbine, troposkein turbine, and circular-, square- or rectangular-shaped turbines) that is installed inside the conduit.
Inventive assembly processes preferably include steps for providing a generator (e.g., generator 110 above the turbine. By way of example, providing a generator begins with installing a frame assembly (e.g., frame assembly 112 shown in
Under operation, the liquid or water impinging upon the blades of the turbine causes a turbine shaft to rotate about its axis. A coupling (e.g., coupling 114 shown in
More importantly, inventive systems and processes which include the provision of a second aperture (e.g., denoted by reference numeral 106 in
Although illustrative embodiments of this invention have been shown and described, other modifications, changes, and substitutions are intended. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the disclosure, as set forth in the following claims