Abstract: A reactive blade turbine system works vertically, horizontally, or at an angle and clockwise or counterclockwise according to blade angle and locking position and adjusts to variations in fluid flow such as changes in tidal currents to generate power more efficiently regardless of direction of fluid flow. A method for generating electrical power from a continuous fluid flow via the reactive turbine system is also provided herein.

Abstract: A device for producing energy includes an air-towed vessel, and at least one water current turbine linked to the vessel by at least one electric cable. The water current turbine is linked to the vessel by at least one mechanical linking cable to be towed by the vessel. The water current turbine is spaced apart from the vessel, which makes it possible to increase the diameter of the turbine and to reduce the interactions between the turbine and the vessel. Moreover, it is then possible to provide a plurality of water current turbines towed by the same vessel.

Abstract: A continuous fluid flow power generator includes an electrical generator with submersible turbine blades in communication with a flow of fluid in a body of water to generate electricity. The generator may include a water tower and a hydro turbine generator to generate electricity through kinetic actions; a float and piston assembly activated by wave action to deliver water to the water tower; kick turbines to create water flow to the water tower through submersible pumps; and a rechargeable battery in communication with the electrical generator and the hydro turbine generator. The generator may also include solar assemblies and windmills to provide supplemental electricity generation for charging the rechargeable battery. The generator may be connectable to a battery bank aboard a vessel or to an electrical grid.

Abstract: A controller for the yaw function is coupled with a yaw system for controlling the operation of yaw motors in the yaw function of a wind turbine. A control signal is provided to the controller that is reflective of a grid condition of an electric grid. The control signal is evaluated, and the controller selectively delays the yaw function based upon the control signal. In another embodiment, the yaw system includes brakes for the yaw motors that are coupled with an independent power supply. The controller selectively delays the yaw function if the brake power supply is not operational.

Abstract: The present invention is a power storage system for use in a body of water, including a cable strung between at least one lower pulley and an upper pulley. A tank arrangement includes an outer tank disposed in the body of water and having an open bottom end, the outer tank fixed with the cable and configured to move between a lowered position and a raised position. An inner tank is disposed within the outer tank and includes an air compressor configured to move air from the outer tank to the inner tank and a dump valve configured to release compressed air within the inner tank into the outer tank. A generator produces electricity as the air within the inner tank is released to cause the outer tank to rise. A second tank arrangement is fixed to an opposing side of the cable.

Abstract: A continuous fluid flow power generator includes an electrical generator with submersible turbine blades in communication with a flow of fluid in a body of water to generate electricity. The generator may include a water tower and a hydro turbine generator to generate electricity through kinetic actions; a float and piston assembly activated by wave action to deliver water to the water tower; kick turbines to create water flow to the water tower through submersible pumps; and a rechargeable battery in communication with the electrical generator and the hydro turbine generator. The generator may also include solar assemblies and windmills to provide supplemental electricity generation for charging the rechargeable battery. The generator may be connectable to a battery bank aboard a vessel or to an electrical grid.

Abstract: This disclosure is directed to hydrodynamic electric generators, including their structural design, methods of deployment, anchoring systems, drive systems and control systems. The system can be scaled from ones that can be hand carried to large, stationary devices that can generate up to and greater than 20 kw in a current of 3 knots. In a stationary system, the device can be anchored to an underwater floor by an anchoring device supported by four adjustable legs. These legs can eliminate the need for extensive mooring lines, providing the device with a small footprint that is non-hazardous to marine animals or vegetation. Individual components, such as rotors, generators and other mechanical components can be modularly installed for easy removal and servicing without having to disturb the entire system.

Abstract: A method is for making a marine drive for propelling a marine vessel in water. The method includes providing a gearcase; installing a propeller shaft assembly that extends forwardly from the gearcase; coupling front and rear propellers to the propeller shaft assembly, forwardly of the gearcase, such that rotation of the propeller shaft assembly causes rotation of the front and rear propellers, respectively, which thereby propels the marine vessel in the water; and reducing deleterious effects of cavitation on the gearcase by the combination of forming the gearcase with a wide trailing end portion, in particular to maintain pressure alongside the gearcase, and configuring the front and rear propellers so that the front propeller absorbs more torque/thrust load than the rear propeller during said rotation.

Abstract: Underwater vehicles capable of self-propulsion are described. An underwater vehicle includes a cross-flow turbine including two or more foils spaced apart from a main shaft. The foils have a pitch that is adjustable under control of a pitch control mechanism. The underwater vehicle also includes a frame supporting the main shaft. The frame enables rotation of the cross-flow turbine. The underwater vehicle additionally includes a generator-motor set including rotor and stator elements. The rotor element is in rotary communication with the main shaft.

Abstract: A method for harnessing wave energy includes providing a vehicle to a body of water, the vehicle. The method includes submerging the vehicle to a depth in the body of water. The method includes operating the motor-generator of the vehicle in the first quadrant of the motor-generator. The method includes detecting a phase of a wave in the body of water based information from the processor of the detected phase. The method includes orienting the vehicle to lag the phase of the wave based on the detected phase of the wave. The method includes synchronizing an inertial acceleration of the vehicle to movement of the wave. The method includes switching the motor-generator to the second quadrant for generation mode to convert energy from the movement of the wave to electrical energy. The method includes storing the energy from the wave in the rechargeable battery source.

Abstract: A floating platform comprised of a tower, buoyant outriggers, and an articulated arm can be used in one embodiment to support an offshore wind turbine. The buoyant articulated arm is positioned with a winch system that supports the tower in a nearly horizontal position during assembly at shore and during transport. The winch and articulated arm elevate the system into its operational position at sea. The tower may include a keel structure to reduce motions and stresses on the system. The floating platform may rotate about an area surrounding an anchor system without active wind alignment equipment. The natural alignment with the wind allows for optimization of the structure, resulting in lighter-weight, less material mass and ultimately lower cost. The horizontal transport alleviates clearance restrictions of many bridges. Requiring neither large cranes nor specialized ships during installation, its ability to raise itself is scalable to large sizes lowering cost.

Abstract: The present invention relates generally to facilities and systems capable of initiating and maintaining vertical flow, upward, within an extended-length water column by inducing changes in density throughout the column. Specifically, the induced (vertical) flow of water within an extended water column that is the present invention is accomplished through fluid aeration, with ambient air, which is directed toward producing ascending water flow rates sufficient to generate hydraulic pressure and hydraulic powered energy, through generated radial force in hydraulic turbines. It is another goal of this invention to utilize air infused water, derived from high-density and low depths, to create said vertical flow and induce turbine actuation through said unaltered, recyclable mediums—air and water—resulting in electrical power generation and desalination.

Abstract: A wave power generation apparatus is disclosed. A wave power generation apparatus according to one embodiment can comprise: a floating body floating on the surface of the sea; a power transmission part, which is connected to the floating body so as to receive power generated according to the movement of the floating body, and moors the floating body on the surface of the sea; and a mooring angle adjustment module for adjusting the mooring angle of the floating body for the power transmission part according to the state of the waves acting on the floating body.

Abstract: A waterwheel assembly for a river or similar body of flowing water includes a waterwheel mounted on a support structure, and one or more buoyant members, wherein waterwheel can move up and down, and the buyout members support part of the weight of the waterwheel so that the waterwheel is able to rise and fall with any change to the river level, and the support structure is secured on land by the river or body of water by means of one or more cantilevered beams. The waterwheel has an axle secured between two vertical posts by means of salable bearings that permit the waterwheel to move up and down.

Abstract: The present invention relates generally to facilities and systems capable of initiating and maintaining vertical flow, upward, within an extended-length water column by inducing changes in density throughout the column. Specifically, the induced (vertical) flow of water within an extended water column that is the present invention is accomplished through fluid aeration, with ambient air, which is directed toward producing ascending water flow rates sufficient to generate hydraulic pressure and hydraulic powered energy, through generated radial force in hydraulic turbines. It is another goal of this invention to utilize air infused water, derived from high-density and low depths, to create said vertical flow and induce turbine actuation through said unaltered, recyclable mediums—air and water—resulting in electrical power generation and desalination.

Abstract: A floating drum turbine is used for generating the electrical energy from the kinetic energy of a water stream (sea wave or river flow) that provides the mechanical energy needed to rotate an electrical generator for generating the electricity. The drum turbine is installed on a buoyant skid anchored to the seabed by some chains/ropes to keep it in a fixed position and direction along the water stream. The turbine is coupled to an electrical generator with a power transmission system, and generates the electricity that is transferred to the coast using a cable system floated on the water surface.

Abstract: A water current catcher system for hydroelectricity generation includes a first L-shaped weir, a second L-shaped weir, a channel opening, an underwater gate assembly, and at least one elevation adjustable hydroelectric generator unit. The first and second L-shaped weir are connected to a subsurface environment and linearly positioned to each other. The channel opening is delineated between the first L-shaped weir and the second L-shaped weir. The underwater gate assembly is integrated into the first L-shaped weir, the second L-shaped weir, and the subsurface environment thus positioning about the channel opening. The elevation adjustable hydroelectric generator unit that includes a first jack-up barge, a second jack-up barge, a waterwheel, and a generator is connected to the subsurface environment and adjacently positioned about the channel opening.

Abstract: A secondary electric power system and method of operation are disclosed. The system contains a grid having an array of turbines by which pressurized fluid is used to generate electricity to power a residential, commercial, agricultural or industrial structure. The secondary system may be a backup power source to the structure when a primary source is temporarily unavailable or may be a primary source in some circumstances. The method pumps fluid from a first pressure to a second pressure and exposes the fluid to a grid of turbine driven generators, the pressure is reduced across the grid to a third pressure that is less than the second. Additionally embodiments of the system are integrated into and incorporate components of other building utilities, e.g. water, sewer and fire control.

Abstract: A water current energy generator comprises a barrel configured to rotate in a water current and a pair of air compressors secured on either side of the barrel. As the barrel spins, the air compressors are actuated and compress air into a cylinder. The compressed air is then capable of being accessed by means of a pneumatic hose.

Abstract: A wind-driven power generating system with a hybrid wind turbine mounted on a floating platform that heels relative to horizontal in the presence of a prevailing wind. The hybrid turbine has a turbine rotor with at least two rotor blades, each mounted to a turbine shaft by at least one strut, and the system is configured so that the shaft forms a predetermined non-zero operating heel angle relative to vertical in the presence of a prevailing wind at a predetermined velocity. The blades and struts are airfoils with predetermined aerodynamic characteristics that generate lift forces with components in the direction of rotation around the shaft of the blades and struts at the operating heel angle to drive an electrical generator carried by the platform. The system can be designed to generate maximum power at the predetermined heel angle or essentially constant power over a range of heel angles.

Abstract: A floating electrical power generator having a three-dimensional (3D) flow passageway configured for increasing the water flow on the paddle wheel to increase the power output.

Abstract: A self-installing offshore column stabilized semi-submersible platform has at least one vertical buoyant ballastable column, a telescoping keel tank or stiffened damper plate movably connected with the vertical column that extends and retracts relative to a lower end thereof, and a tilt and telescoping wind turbine tower assembly pivotally coupled to an upper end of the vertical column telescopes and reciprocates relative thereto between a horizontal retracted position and an axially extended vertical position. A wind turbine with blades is coupled to a top portion of the upper section of the tower assembly. The relative position and weight of the keel tank or damper plate is selectively adjustable to raise or lower the center of gravity of the entire mass of the semi-submersible platform including the wind turbine and tower assembly with respect to the center of buoyancy of the platform.

Abstract: A wind turbine system comprising a plurality of wind turbines mounted to a support structure including a tower, wherein each of the plurality of wind turbines includes a rotor and a power generation system driven by the rotor, and at least one of a rotor blade pitch adjustment means and a generator power control means. The system further includes control means that receives vibration data associated with the support structure and which is configured to determine a damping control command for a respective one of the plurality of wind turbines, wherein the or each of the wind turbines includes a damping controller that receives a damping control command and which is operable to apply a damping control input to one or both of the blade pitch adjustment means and the generator power control means so as to counteract the measured vibration of the support structure.

Abstract: The present invention provides a floating offshore wind turbine capable of suppressing yawing of a nacelle caused by a gyro effect which is a cause of adverse influence of power generating efficiency of a wind turbine and endurance of devices thereof. The floating offshore wind turbine includes a rotor which is rotated by wind, a nacelle in which a rotation shaft of the rotor is accommodated, and a tower including a turning seated bearing which supports the nacelle such that the nacelle can turn with respect to a sea surface to exert a weathercock effect. The tower is provided with yawing suppressing means which suppresses yawing of the nacelle. According to this, it is possible to suppress the yawing of the nacelle generated by a gyro effect caused by yawing generated in the floating body by waves of the sea surface.

Abstract: Provided is a supersonic compressor having a supersonic compressor rotor including a clockable rotor disk allowing restriction or opening of portions of a fluid flow channel of the rotor in order to enhance performance of the rotor during different operational stages, for example rotor start-up or steady state. The supersonic compressor has a first rotor disk, a second rotor disk and a third rotor disk which share a common axis of rotation. The first and second rotor disks are rotatably coupled, and the third rotor disk is disposed between them. The third rotor disk is independently rotatable relative to the first and second disks, and has a raised surface structure for restricting or opening a portion of the flow channel defined by the three rotor disks and at least two vanes. The flow channel contains a supersonic compression ramp and encompasses the raised surface structure.

Abstract: A flowing-water driveable turbine assembly (104) for location in river or sea areas with unidirectional and bidirectional water flows. The turbine assembly comprises a turbine support (106) with positive buoyancy in water. The turbine support (106) is arranged to be anchored by an anchoring system (108) to a water bed. The turbine assembly comprises at least one turbine (110). The positive buoyancy of the turbine assembly in water has an upward force to constrain the turbine support 106 and the at least one turbine (110) to a position of floating equilibrium against a downward force of the anchoring system (108). The turbine assembly may have variable buoyancy, a duct around each turbine for directing water through the turbine to generate power from water flow, and a winch or winches for submerging the turbine assembly or parts thereof.

Abstract: A wind power system comprising a wind turbine resting on a floating support and means for anchoring the system connected to the system by attachment points. The system furthermore comprises means for raising the attachment points above the waterline of the floating support.

Abstract: An offshore wind turbine comprising a buoyancy structure intended to provide a buoyancy force to support the wind turbine, wherein said buoyancy structure comprises at least one floater tank which, in use, contains a pressurized gas.

Abstract: A deployment device and system for a hydrokinetic energy converter such as a hydrokinetic turbine that can be coupled to a generator to produce electricity. The deployment device can include a floatable platform including a central aperture sized to allow a hydrokinetic turbine to be lowered therethrough into water. A pair of deployment swing members are rotatably attached to the platform and located adjacent to the central aperture. Each deployment swing member has a support for connection to an end of a hydrokinetic turbine. Each deployment swing member is rotatably supported for rotating the swing members from a first position in which the swing member and any attached turbine are raised at least partially out of the water, through the central aperture, and to a second position in which the swing member and any attached turbine are lowered beneath the platform at least partially in the water.

Abstract: An underwater turbine mounting includes a rigid tether having one end attached thereto at a pivot, and the other end adapted for connection to an underwater anchorage. The rigid tether is pivotable between a deployment condition and an anchorage condition. The mounting is pivotable between a deployment condition and an operating condition solely by adjusting the buoyancy thereof. The mounting is pivotable between an operating condition and a maintenance condition solely by adjusting the buoyancy thereof.

Abstract: Provided are a floating structure fluid dynamic force use system and a wind-propelled vessel which uses the system whereby it is possible to compensate for overturning moment due to fluid dynamic force and to alleviate both tilting and size increases of a floating structure. A floating structure fluid dynamic force use system (1) comprises an assembly (12) which extracts energy from wind or water, and a floating structure (13) which supports the assembly (12). The assembly (12) comprises a wind receiving part (10) which receives fluid dynamic force, and a support column (11) which supports the wind receiving part (10). The assembly (12) is positioned with the center of gravity (15) thereof below the water line and is supported to be capable of tilting in an arbitrary direction upon the floating structure (13).

Abstract: A propeller has a number of blade surfaces or winglets extending helically around its rotational axis in the most streamlined manner. The winglets gradually project at an increasing distance outward with an arcuate shape, each defining a rearwardly concave channel that increases in volume and degree of encirclement rearward on the propeller. In the front of the propeller, the winglets are shaped so that they have edges angled obliquely and diagonally that conformingly and without cavitation cut into the water and cause it to flow smoothly in the channels. In the middle of the propeller, the winglet edges extend rearward so that water entrained in the channel is directed rearward without centrifugal loss. In the rear portion of the propeller, the channels narrow and reduce in volume so as to expel the water from the concavity.

Abstract: A floating platform including a plurality of pontoons providing buoyancy to the platform, and a ballast section imparting a spatial orientation to the platform. The ballast section includes a high density ballast being an aggregation of rocks, an aggregation of chunks of iron ore, or an aggregation of any other high density material. Further, the ballast section is permeable to a fluid medium in which the platform floats so as to cause a high friction between the high density ballast and the fluid medium.

Abstract: A floating turbine, including a vertical substantially fixed structure such as a pile or cable, a hydroelectric turbine, a connecting piece between the turbine and the structure that is operative to enable vertical motion of the turbine on the surface of the water.

Abstract: A floating wind turbine (1) for electric power production and a method for use of said wind turbine (1), is described, where the wind turbine (1) comprises a hull (2) attached to a supporting column (2?) for a wind turbine (3) which is arranged to be put into rotation by wind force acting on rotor blades (3?), the wind turbine (1) is connected to a buoyancy device (4) by means of a coupling device (5), the buoyancy device (4) is arranged encircling at least a portion of the hull (2), and the buoyancy device (4) is arranged to be able to support at least a portion of the mass of the wind turbine (1), the coupling device (5) is a rotary coupling arranged in such a way that the wind turbine (1) is arranged to be able to rotate an angle from an essentially vertical position towards a horizontal position, or the opposite, and the hull (2) is provided with an adjustable ballast means (9, 12) arranged to be able to balance the wind turbine (1) about the rotary coupling (5) in any position between said positions.

Abstract: Support platform for wind generators, comprising a central body (5) provided with a seat engaging with a final section (4) of a pillar (1) of a wind generator (2); this central body (5) is connected by means of a series of radial elements (6) to an annular floating structure (7) and provided internally with position-adjusting means (10) cooperating on the one hand with the base of this final section (4) of the pillar (1) and on the other hand with suitable support elements (9), these position-adjusting means (10) being able to receive and contain a given quantity of fluid and vary the height of the wind generator (2) by means of the raising or lowering of said pillar (1).

Abstract: A platform-like device for generating electricity from moving fluids has two has at least two fluid turbines coupled to one another through a frame. The fluid turbines are adapted to rotate in opposite directions. The fluid turbines also provide buoyancy for the platform so that the platform is self supporting in the water. The fluid turbines preferably have helicoid flights (screw-like threads) mounted to generally prolate casings. The fluid turbines preferably connect to electric generators through belt, chain-drive, or other transmission systems. The platform may additional support a wind turbine.

Abstract: An offshore wind turbine generator comprises an elongated, buoyant tower, having an internal service tube, the service tube extending from the lower end of the tower to above the waterline when in use, a connection arrangement comprising an upper connection assembly, and a lower connection assembly. An intermediate tension/torsion leg is arranged between the upper and lower connection assemblies. The connection assembly is adapted for lowering and raising within the service tube.

Abstract: A method of deploying offshore wind turbine assemblies includes mounting a wind turbine assembly horizontally on a vessel and transporting the wind turbine assembly to an offshore site. The wind turbine assembly is raised to a vertical condition at the site and attached to anchor weights. Blades are attached to the turbine head after the wind turbine assembly is in the vertical condition. In one embodiment, the wind turbine assembly can include a tower including tapered lower and upper sections joined together at their respective wide ends, a turbine head connected to the upper section, and a platform connected to the lower section. The platform includes a buoy tank partially filled with ballast to provide mass and buoyancy. A wave piercing cowling is rotatively attached to the lower section. The turbine head can include an adjustable journal bearing, scabbard blade mounts, and a gearless induction generator with flux adjusting capabilities.

Abstract: The present invention relates to a device and method for capturing the kinetic energy of a fluid and converting it to rotational, electrical or mechanical energy, the device including a rotating bar mechanism for enabling rotation of a flow-capturing blade around a central axis of the device while retaining the flow-capturing blade in an orientation perpendicular to the fluid flow direction throughout the rotation cycle.

Abstract: A floating offshore wind turbine comprises a rotor with a plurality of blades, a nacelle and a nacelle support structure having a central longitudinal axis. A plurality of tuned mass damping configurations is arranged around the central longitudinal axis of the nacelle support structure to dampen vibrations in all 6 degrees of freedom.

Abstract: The invention relates to an device for production of energy from currents in water, comprising a first element (10), a second element (20) and a plurality of turbine modules (750) connected to the first element. The second element is mounted on the first element in an approximately perpendicular relationship, the first element is adapted for submersion below a water surface, and an upper part of the second element projects up above the water surface when the plant is in production. The invention also relates to an anchoring device for a floating plant (10, 20), comprising mooring lines (24a, 24b) which are connected at one of their respective ends to the plant and which are connected at their respective second ends to buoys (50, 52), where the mooring lines (24a, 24b) extend substantially horizontally between the plant and the respective buoys.

Abstract: A kinetic hydropower generation system has a turbine and a generator coupled to the turbine. An underwater intake nozzle assembly is fluidly coupled to the turbine. For one embodiment, an underwater tower nozzle may be fluidly coupled between the turbine and the underwater intake nozzle assembly. The underwater intake nozzle assembly may include a collector and a converging nozzle.

Abstract: The invention relates to the field of methods and floating platforms for exploiting wind energy offshore. In particular, the invention provides a floating platform (1) anchored to at least one anchor point (7, 7?), including a wind turbine (2), and a shift device for shifting the wind turbine (2), which device is configured to shift the wind turbine (2) as a function of a set of parameters, including wind direction (V), in order to minimize the aerodynamic wake effects, and the invention also provides a method of exploiting wind energy by means of a set of floating platforms (1), each of which includes at least one wind turbine (2) and is anchored to at least one anchor point (7,7?). In this method, at least one wind turbine (2) of said set of floating platforms is shifted as a function of a set of parameters, including wind direction (V) in order to minimize the aerodynamic wake effects and in order to maximize the power generation of the set of wind turbines.

Abstract: A support system for at least one water drivable turbine (1) that when in operation is immersed in a column of flowing water, characterized in that the system includes a deck or raft (3) for supporting said at least one turbine when immersed, the deck or raft (3) having an inherent buoyancy which is such as to enable the deck or raft (3) to rise through the column of water upon reduction of the buoyancy, the arrangement being such that the associated turbine or turbines (1) can be raised above the surface of said column in order to access the turbine for maintenance purposes.

Abstract: A series of helical Savonius turbine generators for use in the ocean, each turbine generator being an independent system, but all sharing a common mooring/bus-bar cable. An anchor connects one generator to the ocean floor, and a buoyancy device system buoys the turbines so that they can generate power from passing currents. The generators are coreless, and generate electrical or hydraulic power. The turbine blades rotate on bearings that are lubricated with ambient water. A control system separately tracks the power generation level of each turbine, and controls the buoyancy of the buoyancy device system.

Abstract: A floating structure has a hull and a propeller propulsion system having a gear arrangement that is connected via a first intermediate shaft to at least one electromotor, the electromotor being arranged onboard the floating structure, and via a second intermediate shaft to a propeller. The gear arrangement has an angular gear. The first intermediate shaft forms an angle relative to the second intermediate shaft. The gear arrangement is arranged as a separate unit in an appendage or addition to the hull of the floating structure. The appendage or addition is designed to allow an interior thereof to be accessed from within the vessel, whereby maintenance, replacement, or repairs of the gear arrangement can be carried out. The angular gear has at least one angled gearwheel set and one cylindrical gearwheel set.

Abstract: A wind turbine has an impeller surrounded by a turbine shroud and/or an ejector shroud, wherein the turbine shroud and/or the ejector shroud include inflatable portions and/or flexible inflatable portions. In some embodiments, the turbine shroud and/or the ejector shroud include internal rib members whose shape or length can be changed to alter the characteristics of the wind turbine.

Abstract: The present invention relates to a floating wind turbine (1), comprising a rotor (3), an upper column (5) connected to the rotor (3), and a stabilizer tank (4) disposed between the upper column (5) and a lower column (6), and an anchor (7) rotatably connected to the lower column (6), the stabilizer tank (4) having its centre of buoyancy eccentrically arranged in relation to a longitudinal centre axis through the upper (5) and the lower (6) column. The invention also relates to a method for the mounting and installation of a floating wind turbine (1).

Abstract: Floating energy producing plant (1), comprising at least three wind generators (2) attached to a common floating unit which can be placed on water independent of placement and water depth. The unit comprises a frame work (F) constructed of pipes (4) connected in at least three attachment points having the shape of nodes (3, 5). The pipes (4) are sealed in their respective ends (4a, 4b) and forms separate floating parts adapted to be connected to the nodes (3, 5).