Abstract: An inert gas fuel consisting essentially of a precise, homogeneous mixture of helium, neon, argon, krypton and xenon. Apparatus for preparing the fuel includes a mixing chamber, tubing to allow movement of each inert gas into and through the various stages of the apparatus, a plurality of electric coils for producing magnetic fields, an ion gauge, ionizers, cathode ray tubes, filters, a polarizer and a high frequency generator. An engine for extracting useful work from the fuel has at least two closed cylinders for fuel, each cylinder being defined by a head and a piston. A plurality of electrodes extend into each chamber, some containing low level radioactive material. The head has a generally concave depression facing a generally semi-toroidal depression in the surface of the piston. The piston is axially movable with respect to the head from a first position to a second position and back, which linear motion is converted to rotary motion by a crankshaft.

Abstract: Apparatus for producing useful work from available heat at super-ambient temperature. The present apparatus includes a pair of working fluid units which supply pressurized vapor to a utilization apparatus. Each working fluid unit includes a generator for boiling the working fluid in response to available heat, and a recovery vessel for receiving condensed working fluid exhausted from the utilization apparatus after expansion to produce useful work. The condensed working fluid from the utilization apparatus is alternatively returned to the recovery vessel associated with the generator presently receiving heat to generate pressurized vapor.

Abstract: A system is described for acoustically controlled rotation of a levitated object (12), which avoids deformation of a levitated liquid object. Acoustic waves (50, 52 in FIG. 6) of the same wavelength are directed along perpendicular directions across the object, and with the relative phases of the acoustic waves repeatedly switched so that one wave alternately leads and lags the other by 90.degree.. The amount of torque for rotating the object, and the direction of rotation, are controlled by controlling the proportion of time one wave leads the other and selecting which wave leads the other most of the time.

Abstract: A gas turbine unit with auxiliary devices and, in the region of the compressor, a compressed air branch or gas under pressure for the operation of the gas turbine. The compressed air branched off from the compressor, or the gas under pressure, serves for direct drive of an energy exchanger which, while avoiding transmissions and the like, generates the oscillating or rotating movement necessary for driving the auxiliary apparatus of the gas turbine unit or the entire system formed therewith. The energy exchanger has working cylinder chambers, and the associated auxiliary apparatus, embodied as pumps, has displacement cylinder chambers, in which chambers pistons embodied in one piece or rigidly connected with each other are arranged axially movable.

Abstract: A power plant and process for converting gas expanding and contracting energy sources into useful forms of energy and utilizing gravitational force, wherein a piston containing a magnet and able to fall within an enclosed cylinder, having a non-magnetically-responsive center portion surrounded by an induction coil is repeatedly impelled upwards thereby inducing an alternating electric current in the coil. In the first alternate embodiment, concentrated solar energy is directed onto a liquid in the bottom of the cylinder to provide an expanding gas beneath the piston. As the piston moves upwards within the cylinder, compressed air is pumped into a reservoir, after which it is available to serve as a source of stored energy.

Abstract: The disclosure is directed to an acoustical heat pumping engine without moving seals. A tubular housing holds a compressible fluid capable of supporting an acoustical standing wave. An acoustical driver is disposed at one end of the housing and the other end is capped. A second thermodynamic medium is disposed in the housing near to but spaced from the capped end. Heat is pumped along the second thermodynamic medium toward the capped end as a consequence both of the pressure oscillation due to the driver and imperfect thermal contact between the fluid and the second thermodynamic medium.

Abstract: A system is described for acoustically moving an object within a chamber, by applying wavelengths of different modes to the chamber to move the object between pressure wells formed by the modes. In one system, the object (96, FIG. 7) is placed in a first end portion of the chamber while a resonant mode is applied along the length of the chamber that produces a pressure well (86) at that location. The frequency is then switched to a second mode that produces a pressure well (100) at the center of the chamber, to draw the object thereto. When the object reaches the second pressure well and is still travelling towards the second end of the chamber, the acoustic frequency is again shifted to a third mode (which may equal the first mode) that has a pressure well (106) in the second end portion of the chamber, to draw the object thereto.

Abstract: A system is described for use with acoustically levitated objects, which enables close control of rotation of the object. One system includes transducers (18, 20, 22) that propagate acoustic waves along the three dimensions (X, Y, Z) of a chamber (16) of rectangular cross section. Each transducer generates a first wave which is resonant to a corresponding chamber dimension to acoustically levitate an object, and additional higher frequency resonant wavelengths for controlling rotation of the object. The three chamber dimensions and the corresponding three levitation modes (resonant wavelengths) are all different, to avoid degeneracy, or interference, of waves with one another, that could have an effect on object rotation. Only the higher frequencies, with pairs of them (e.g. 50, 52) having the same wavelength, are utilized to control rotation, so that rotation is controlled independently of levitation and about any arbitrarily chosen axis.

Abstract: A system and method of atmospheric thermal energy conversion is disclosed utilizing pressurized inflatable rising conduit. The method includes the steps of: (a) providing warm or cold gas at a predetermined elevation; (b) transporting the gas vertically from the predetermined elevation to a different elevation through a thin-walled, inflatable, rising conduit, thereby providing gas within the conduit with a density which causes the gas to flow through the conduit; (c) converting the energy of the flowing gas by passing the gas through a transducer; (d) pressurizing the conduit from the inside with the transported gas to thereby inflate and support the thin-walled, inflatable, rising conduit.

Abstract: A sealed package for pressurizing the contents of dispensing containers. The package contains chemicals which react to develop gas pressure to expand the package when in the dispensing container. A series of sequentially rupturable pockets add further increments of internal pressure as dispensing proceeds. These pockets, and additional pockets containing chemicals for initiating package pressurization, are formed in an outer film heat-sealed to a second outer film to define the package. The rupturable pockets are covered with a tape to maintain the chemicals isolated until rupture is effected by progressive lift-off of the tape as the package expands.

Abstract: A self-contained, self-powered hot air distribution system is provided which utilizes a Stirling engine, the hot end of the displacement cylinder of which extends into a fireplace or other heat source, with a fan or blower which is powered by the Stirling engine blowing air over the cold end of the displacement cylinder and into the fireplace or other heat source and back out into an area to be space heated.

Abstract: This is an improvement to a travelling wave heat engine. The latter uses acoustical travelling waves to force a gas in a differentially heated regenerator to undergo a Stirling thermodynamic cycle and thereby converts thermal energy into acoustical energy or vice versa, depending on the direction of the wave propagation. This patent concerns the addition of a resonant cavity around the regenerator to superimpose a standing wave to the travelling wave in order to augment the pressure component of the travelling wave without adding to the velocity component. This increases the level of acoustical power that can be put through the engine for a given level of regenerator viscous loss and so increases the engine's specific power which is limited by regenerator viscous losses.

Abstract: A saturated non-convective solar pond is employed as an unmixing device in conjunction with reverse electrodialysis or pressure-retarded osmosis for power generation.

Abstract: Thermal energy is converted into rotational energy by using the expansion of a fluid medium to propel a plurality of pistons within at least one continuous, closed-loop passageway mounted on a rotatable platform. In at least one region of the passageway, the pistons must move inwardly against centrifugal force as the platform rotates. In at least one other region of the passageway, the pistons are moved outwardly under the influence of centrifugal force. Means are provided for imparting force to successive ones of the pistons to propel them against centrifugal force in said one region; while means are provided for converting the energy of pistons moving outwardly under the influence of centrifugal force in said other region into rotational energy. This rotational energy is used to drive gears mounted on the platform which mesh with a stationary gear carried beneath the platform to cause rotation of the platform about its rotational axis.

Abstract: A cyclic energy transformation apparatus and method for developing streams of working fluid flow with different energy characteristics. The working fluid being passed through a container which effectuates a vortical ring flow pattern. The fluid in one stream is discharged from the container as high pressure flow. The fluid in another stream is discharged from the container as a high temperature flow. The separate streams can be used independently or in conjunction with each other for performing useful work.

Abstract: Apparatus for degrading safety fuel of the type containing an anti-misting polymer and comprising a bank of interfitting stators and rotors with a plenum chamber at some station along the bank, whereby rotation of the rotors will cause safety fuel pumped through the apparatus to be subjected to sufficient shear and local acceleration to be degraded to a state acceptable for engines and their control apparatus.

Abstract: Gas and combined gas/steam power cycles in which chemical energy is stored in a gaseous working fluid by radiolytic dissociation at a temperature below the temperature of thermodynamic macroscopic dissociation, such that the dissociated portion of the working fluid exists under conditions of macroscopic thermal non-equilibrium. The dissociated fluid components are then recombined with the energy of recombination adding heat to the working fluid for extraction in the power cycle.

Abstract: A mass transit system is provided which derives its basic energy from the solar system and recovered heat energy.

Abstract: A power-producing device, comprising a vertically oriented chamber of enormous height, incorporating within its upper end an electric motor-driven, aftercooled air compressor, being connected via suitable power transmission, to an electric generator driving, reheated air turbine, located within the lower chamber end. Atmospheric air is compressed at a given rate of flow to a given pressure into the upper chamber end, which, due to the gravitational force exerted on its compressed mass, and due to the chamber height, is expanded within the turbine at the lower chamber end at an equal rate of flow, but, at a substantially higher pressure, and at a substantial gain in energy, thus, producing a substantially greater amount of work than is consumed by the compressor.

Abstract: In the embodiment shown, the device comprises a pair of turbine wheels, rotatively journaled, each having a peripheral, concave channel. The wheels are journaled to close onto each other, in close proximity, to define of their channels a circular aperture. A conduit is directed to impel rounds of shot into the aperture, so that rotary torque power will be derived from the turbine wheels. A supply of pressured steam accelerates the rounds through the conduit to the aperture, and a feed wheel singly and successively introduces the shot into the conduit. A drive belt fixed around a hub on the feed wheel and a hub on one of the turbine wheels imparts rotation to the feed wheel, and the spent-missile end of the conduit opens onto the feed wheel to cause the latter to store and advance shot.

Abstract: A reciprocating engine utilizing the mutual repulsion of charged air particles to drive a work-producing means. The engine has pistons reciprocating in cylinders with cylinder spaces between cylinder heads and the pistons. A first enclosed porous conductive electrode is located in fluid flow communication with the cylinder space, typically within the cylinder space itself. The first porous electrode is electrically connected to a second conductive porous electrode in a separate housing. Air is admitted into the first electrode while fuel is admitted into the second electrode. As the air in the cylinder space and first electrode is compressed as the piston moves toward the cylinder head, a current flow takes place from the first electrode to the second electrode because of valance attraction between fuel molecules and oxygen electrons resulting in the ionization of oxygen and fuel.

Abstract: Apparatus for controlling and taking up the axial displacement of large rotating cylinders, comprising a pair of end bearings, of which one is provided with driven rollers, while the other is provided with idle rollers, one of which is carried by a bearing orientable about a vertical axis. A first transducer senses the axial displacement of the cylinder and its output is connected to an input to a first device effecting a comparison with a reference signal; the output of the first comparing device is connected through an amplifier to an input to a second comparing device, a second input of which is connected to the output of a second transducer sensing the displacement of the guide roller bearing. The output of the second comparing device controls a servoactuator mechanically connected to the orientable bearing of the guide roller.

Abstract: Liquid is continuously endowed with mechanical energy by continuously osmosing it across an osmotic membrane across which is maintained a substantial pressure difference of osmotic pressures. Continuity is insured by continuously flowing hypotonic liquid against and away from the hypotonic surface of the membrane, continuously flowing hypertonic liquid against and away from the hypertonic surface of the membrane, and continuously flowing permeate essentially limitlessly away from the hypertonic surface. The substantial osmotic pressure difference across the membrane is maintained, in part, by keeping the hypertonic liquid at or near saturation.

Abstract: In the embodiments shown, the device comprises a turbine wheel, rotatively journaled, having a peripheral, grooved surface onto which rounds of shot are impelled, under steam pressure, to rotate the wheel so that torque power might be derived therefrom. The turbine wheel, in turn, rotates a pulley -- by means of a drive belt -- which operates a sluice-type gating device. The latter device cyclically opens and closes off the pressured steam supply, and feeds a missile -- a round of shot -- to a conduit which terminates in adjacency to the turbine wheel, in order that the round, the missile, will be impelled through the conduit to impact upon the grooved surface of the turbine wheel and deliver a frictional, glancing, energy-transferring blow to the turbine wheel. The turbine wheel is rotatively carried on a support which is pivotally mounted, so that the turbine wheel can be moved into and out of proximity with the missile-impelling conduit in order to optimize missile impact.

Abstract: Sound waves are utilized to apply torque to a body in an enclosure of square cross section, by driving two transducers located on perpendicular walls of an enclosure, at the same frequency but at a predetermined phase difference such as 90.degree.. The torque is a first order effect, so that large and controlled rotational speeds can be obtained.

Abstract: A heat engine that rotates on a shaft set at an angle to the lines of force of a gravitational or centrifugal field. Elongated chambers (divers) are arranged radially and about the shaft with their long axes parallel to the shaft. There are an equal number of hot and cold divers. Each cold diver connects through its base, so a liquid may flow between, with other cold divers located about the shaft. Each hot diver connects through its base, so liquid may flow between, with other hot divers located about the shaft. Each cold diver is connected from its top, so that gas may pass between, through a suitable regenerator to the top of one warm diver. The so-connected pairs of divers are arranged so that the warm diver is always ahead of the cold diver some phase angle 19 radially about the shaft. The divers are filled approximately 1/2 full of liquid and 1/2 full of a gas. As the shaft turns the phase angle causes the gas to flow from warm to cold to warm diver.

Abstract: A method and apparatus for converting thermal energy to rotational energy by impressing a contained fluid with a thermal gradient in the presence of a centrifugal force field.

Abstract: A traveling wave heat engine can be used both as a heat engine and a heat pump. When it operates as an engine, thermal energy is converted into acoustical traveling waves from an acoustical wave source, which if desired, can be further converted into more conventional forms of electrical and mechanical power. When it operates as a heat pump, acoustical traveling waves supply the motivating force to pump heat. An object such as a flame holding screen, heat exchanger, or regenerator creates a stationary temperature gradient in the compressible working fluid of the engine. As acoustical traveling waves pass through this temperature gradient, they cause the fluid there to move through the gradient and back and so be heated or cooled in conjunction with the compression and expansion phases of the wave.

Abstract: The method converts a conventional four cycle internal combustion engine into a single acting reversible steam, or fluid pressure, operated engine by changing the timing cycle of the valves relative to the crankshaft and connecting the valve ports to a reversing valve for admitting live steam to the intake ports while connecting the exhaust ports to the atmosphere, and for reversing the connection, selectively.

Abstract: High-temperature (1200-1500K) electrolysis of water and recombination of the products in a medium-temperature (530K) fuel cell achieve a practical efficiency exceeding 50%. A solid electrolyte is chosen for the electrolytic cell and in combination with the Bacon fuel cell, which offers high efficiency and automatic replenishing of water vapor into the cycle realizes a high-efficiency electrochemical cycle. Both high-temperature, gas-cooled reactors and conventional combustion processes may be used as heat sources. Unconventional heat sources, such as concentrated solar energy, can also be used. A regenerative counterflow heat exchanger and a waste-heat power plant serve as energy-conserving devices. An important feature of this cycle is the flexibility of operation that can be achieved by adding hydrogen storage. Switching among power-generating, load-averaging, and hydrogen-generating modes can then be done by simple gas-flow valves.

Abstract: A method of recovering energy by means of a cyclic thermodynamic process which is induced by means of a medium comprising at least two substances or groups of substances, one of which substances is separated from the other at a point w' defining a first thermodynamic parameter of the medium and combined with the other one of said substances at a second point w" defining second thermodynamic parameter of the medium while a differential in total pressure of the medium is maintained between the two points. The separation and combination of the two substances are induced by diffusion whereby one of the substances or groups of substances is diffused out of the other one of the substances or groups of substances at the first point and diffused into the other substances at the second point.

Abstract: An integrated power generating plant includes a fuel cell for generating electrical energy directly, an auxiliary power generating plant that utilizes both the sensible heat and the heating value of effluents from the fuel cell by using working fluids in a closed cycle. The working fluid is vaporized by sensible heat and is superheated by combusting incompletely reacted fuels from the fuel cell.

Abstract: A shaft-driven power device, such as an electric generator or pump, is mounted on a base which is subjected to fluctuating movements, such as those of waves in a body of water or those of an automotive vehicle. An input shaft at the upper end of the power device is connected by a rigid arm to an off-center weight located just slightly above the base. The weight may be adjustable and replaceable. The power device may be spring-mounted on the base.

Abstract: A plurality of translation rods are mounted in a cage for pivoting about a common axis and pass through the pivot axis, being at fixed circumferentially spaced positions but movable bidirectionally along their individual axes during rotation about the fixed axis shaft. Cam follower rods pivotably mounted on respective ends of the translation rods are slidable axially relative to their axis and through their pivot axis. The cam follower rods carry rotatable cam followers through tension springs, which normally maintain the cam followers at a predetermined distance from the cam follower rod pivot axis in the absence of cam follower contact with a fixed cam mounted in juxtaposition to the path of the rotation of the translation rods. The major surface of the fixed cam is generally at right angles to the direction of constant forces applied to respective ends of each translation rod.

Abstract: An engine having a main power turbine operating on the Brayton cycle, has its air supply furnished by a compressor independently driven by a Rankine turine which derives its heat energy from the exhaust of the Brayton turbine. The engine is constructed in modules. One module consists primarily of a single stage Brayton turbine, with an output gearing system, and a coaxial extension containing an intercycle heat exchanger. A second module comprises a single stage Rankine turbine and a single stage compressor driven thereby for supplying air to the Brayton turbine, a feed pump for the Rankine fluid interposed between the Rankine turbine and the compressor, and accessory devices driven by the Rankine turbine for starting the engine. The second module has its axis perpendicular to the axis of the first-mentioned module. A condenser-regenerator module is disposed in a plane perpendicular to the axis of the second module and parallel to the axis of the first-mentioned module.

Abstract: This invention provides novel mechanical work generating means. Basically, the novel mechanical work generating means provided by the present invention comprise: first means for mechanically generating a heat component of work; second means, mechanically interconnected to the first means, for mechanically generating a non-heat component of work; and third means, mechanically interconnected to the first and second means, for combining the heat and non-heat components of work into a resultant mechanical work output.

Abstract: A multirotary energy conversion valve comprising inlet and outlet passages interposed by meshing pairs of inlet and outlet rotors of unequal constant volume displacements with an enclosed channel in between having energy conversion means and additionally interposed by meshing intermediate rotors of unequal constant volume displacements with at least one rotary linkage connecting an inlet and an outlet rotor and additionally an intermediate rotor in synchronous rotation about one axis, said valve being applicable in a range including check valves, heat pumps, heat engines, vacuum pumps, vapor flash valves, cool engines, direct air conditioners and nuclear fusion devices.

Abstract: A device for rotating a turbine, particularly during starting, comprises a positive displacement-type main oil pump which has a main pump suction which is connected to the discharge of a high pressure oil pump which also has a connection to supply oil to the bearings. An auxiliary oil pump is mechanically coupled to the high pressure pump and it is also hydraulically connected in series to the high pressure pump. When the pressure builds up between the high pressure pump and the main pump, the main pump may be driven as a motor by the high pressure pump to effect a turning of the turbine.

Abstract: An apparatus and method for separating hydrogen and oxygen from water molecules. A solar reflecting means reflects solar energy onto a water containing tank to boil water contained therein and form steam. The steam is transferred either to a turbine-generator assembly for producing power, or to a dissociating means for producing hydrogen and oxygen. The steam in the dissociating means is forced to traverse a spiral path wherein it undergoes a circular motion to subject it to centrifugal force while contacting a heat transfer surface. Solar energy is concentrated on the heat transfer surface and heat in amounts sufficient to raise the temperature of the steam to the dissociation temperature thereof is transferred thereto. Hydrogen and oxygen are separated from each other by the centrifugal forces, and are withdrawn from the dissociating means. An electric starter and means for moving solar reflecting means are also disclosed.

Abstract: An energy converter of the type primarily intended for transforming thermal energy into mechanical energy. The converter accomplishes this transformation by using heat to expand a fluid, resulting in movement of a mass which is in turn attached to a flywheel surrounding an axle. Moving the mass imbalances the flywheel causing its rotation. A usable work force is generated by this rotation.

Abstract: An accumulator arrangement for the storage and release of braking energy, and for the braking and driving of a rotating shaft by means of a flywheel. The rotating shaft which is to be braked or driven, is connected to a drive or gear unit having 2.degree. of freedom; one output of which is coupled to the flywheel via an installation operable either as a generator or a motor, and whose other output is connected with a second installation operable as a generator or a motor, and the two installations are connected with each other for energy transmission, preferably through a buffer or shock absorbing device.

Abstract: An air driven engine of the reciprocating piston type wherein the pistons are each disposed in their own cylinder and connected in cranking relation to the crank shaft that is the powered component of the engine, in which the piston power strokes are effected using heated air under pressure, and their return strokes are accentuated by exposing the working surfaces of the pistons to a cooled source of vacuum. Timer mechanisms are provided for controlling the sequencing of the differential force applications to the pistons. The sources of air pressure and vacuum are tanks associated with the engine. The apparatus includes an air pump operated as required through a crank shaft to restore the pressure and vacuum tanks to the desired pressure levels, this being done by recycling the air through the system with adequate make up as required to replace energy losses due to friction and leakage.

Abstract: A superconducting microwave engine that achieves mechanical to microwave rgy conversion or microwave to mechanical energy conversion. Such is accomplished by employing a superconducting resonator to increase the decay time of the microwaves inside the resonator and thereby provide the resonator with sufficient time to adiabatically deform and change its eigenfrequency so as to effect a change in the frequency and corresponding energy state of such microwaves in accordance with the Boltzmann-Ehrenfest Theorm. This invention may be in the form of a cylindrical cavity and piston combination, a cavity and vibrating diaphragm combination, or a cylindrical cavity and concentric rotor combination.

Abstract: An internal combustion engine in which heat is derived from the engine cooling system and/or the exhaust to heat a working fluid in a closed circulatory system. This heat transforms the working fluid into a gas which is delivered to a turbine which drives a generator. The generator delivers DC current to an electrolysis cell in which water is decomposed. The water is decomposed by the electric current into its oxygen and hydrogen components. The oxygen is passed to the air intake of the engine carburetors, while the hydrogen is conveyed to a carburetor therefor. Also included is a carburetor for conventional hydrocarbon fuels. The two carburetors are connected by linkage which may be operated either manually or by pressure to vary the ratio of the carbureted fuels which are delivered to the engine.

Abstract: A superconducting microwave engine that achieves mechanical to microwave rgy conversion or microwave to mechanical energy conversion. Such is accomplished by employing a superconducting resonator to increase the decay time of the microwaves inside the resonator and thereby provide the resonator with sufficient time to adiabatically deform and change its eigenfrequency so as to effect a change in the frequency and corresponding energy state of such microwaves in accordance with the Boltzmann-Ehrenfest Theorm. This invention may be in the form of a cylindrical cavity and piston combination, a cavity and vibrating diaphragm combination, or a cylindrical cavity and concentric rotor combination.

Abstract: The small temperature differential between a warmer zone and a colder zone is exploited to produce work by confining a liquid having a temperature between the temperatures of the warmer and colder zones within a substantially closed air-free chamber in the warmer zone so as to vaporize part of the liquid and drive the remainder by its own vapor pressure to perform work by conversions of the potential or kinetic energy of the liquid. The liquid can pass over and drive a turbine for example. The liquid then flows into another chamber closed to the atmosphere. Once the liquid has been transferred from the first to the second chamber, the chambers may be functionally interchanged or the liquid again transferred to the first chamber.

Abstract: A vortex tube construction in which the cold and hot fluids are recirculated to the inlet and energy is extracted from or added to the fluids either by heat exchange or by mechanical removal. This concept is adapted for other devices in which a flow of substantially homogeneous fluid is divided into separate flows at different energy levels.

Abstract: The method of purging entrained air or vapor from fuel stored in two or more tanks in an aircraft, and more particularly in multi-engine aircraft during crossfeed fuel delivery when the aircraft is climbing to altitude, which method consists of reversing the fuel booster pump, or pumps, in the temporarily unused tank, or tanks, while all fuel is withdrawn from one tank to supply the engines, whereby the fuel agitation produced by the reversed pump or pumps effectively frees the entrained air or vapor from the fuel to escape to atmosphere through the fuel tank vent system.

Abstract: An engine is provided which will greatly reduce atmospheric pollution and noise by providing a sealed system engine power source which has no exhaust nor intake ports. The engine includes a spherical hollow pressure chamber which is provided with a reflecting mirror surface. A noble gas mixture within the chamber is energized by electrodes and work is derived from the expansion of the gas mixture against a piston.

Abstract: A new and improved low-speed, high-torgue power unit including a power means that is mounted on a drive wheel for rotation in a receptacle holding a body of fluid. The power means includes a propelling means which acts against the fluid body to rotate the drive wheel about a power output shaft on which the drive wheel is mounted. A movable gate means may be provided with the receptable to restrict circular flow of the fluid and increase thrust of the propelling means.