Showing papers on "Propulsion published in 1982"

System for controlling the propulsion on motor vehicles

Abstract: A system for controlling the propulsion on motor vehicles which not only enables the output torque of the drive unit of the vehicle to be utilized in an optimum manner in critical driving situations, especially under extreme road conditions, but also endows the vehicle with good stability and enhanced driving safety. A comparator is provided, in a propulsion control system which is triggered by at least one presettable or permanently preset threshold value of the speed of the vehicle, and generating an output signal causing the drive torque to be reduced, as soon as this threshold value is exceeded and a signal is present, which indicates that an individual wheel brake is being activated and/or that one of the driven wheels is tending to spin. The threshold value of the speed of the vehicle, which value governs the control process, is preferably regulated in accordance with the transverse acceleration which acts on the vehicle whenever it follows a curved path.

Inertial energy interchange system with energy makeup by combustion engine on demand

Abstract: Vehicle propulsion system or the like characterized by energy interchange between a plurality of flywheel assemblies each including a driving/driven induction motor/generator, and a plurality of vehicle drive wheel assemblies including drive wheels each directly driving/driven by an induction motor/generator, with energy makeup provided by a heat engine driven generator means, operated on demand, such energy interchange being by means of a multi-directional bus to which the flywheel and drive wheel motor/generators are selectively connected by variable frequency switch means and to which the engine driven generator is connected when operating, the switching being under control of a digital computer type controller, the controller receiving as inputs various vehicle operating conditions including flywheel, drive wheel, brake, steering angle and speed control positions, and bus voltage and heat engine driven generator operating condition, and the controller generating switch means controlling outputs causing energy transfer from or to the bus and to or from the drive wheel motor/generators to accelerate or decelerate the vehicle responsive to operator inputs, and causing energy transfer from or to the bus and to or from the flywheel motor/generators when the bus voltage is greater than or less than a predetermined value and to maintain the flywheels at substantially equal rotational speeds, and operating the heat engine and cause electrical energy transfer from the engine driven generator means to the bus whenever the total energy available from the motion of the vehicle and the kinetic energy of the flywheels is less than a predetermined value.

Energy efficient engine high-pressure turbine detailed design report

Abstract: The energy efficient engine high-pressure turbine is a single stage system based on technology advancements in the areas of aerodynamics, structures and materials to achieve high performance, low operating economics and durability commensurate with commercial service requirements. Low loss performance features combined with a low through-flow velocity approach results in a predicted efficiency of 88.8 for a flight propulsion system. Turbine airfoil durability goals are achieved through the use of advanced high-strength and high-temperature capability single crystal materials and effective cooling management. Overall, this design reflects a considerable extension in turbine technology that is applicable to future, energy efficient gas-turbine engines.

A Theory of Wave Devouring Propulsion (4th Report)

Abstract: In the previous report, a possibility of wave devouring propulsion was discussed qualitatively under the assumption that wave energy is ideally converted into thrust. Furthermore, as a realization of wave devouring propulsion, thrust generation by an oscillatory hydrofoil was discussed on the basis of Wu's theory. And free surface effects which had been neglected in Wu's theory were introduced approximately, and the importance of the free surface effects was pointed out with the results for a linear Wells turbine (non-oscillatory hydrofoil).In the present report, a possibility of the idealized wave devouring propulsion is treated more quantitatively, and the advance speed effect on the wave drift force is correctly introduced under the assumption of the perfect absorption of wave energy.As a main subject of the present report, a concept of power free motions of a hydrofoil in a wave is explained as a basis of passive-type wave devouring propulsion, and it is discussed how to choose an optimized motion among the power free motions. And the importance of the optimized motion is strongly demonstrated. Similar results have already been obtained for thrust constant motions by Wu.The effect of depth of submergence on wave devouring efficiency of a linear Wells turbine is also discussed, and a possibility of an optimum depth of submergence is suggested.

Evaluation of wind tunnel performance testings of an advanced 45 deg swept 8-bladed propeller at Mach numbers from 0.45 to 0.85

Abstract: The increased emphasis of fuel conservation in the world and the rapid increase in the cost of jet fuel has stimulated a series of studies of both conventional and unconventional propulsion systems for commercial aircraft. The results of these studies indicate that a fuel saving of 15 to 30 percent may be realized by the use of an advanced high-speed turboprop (Prop-Fan) compared to aircraft equipped with high bypass turbofan engines of equivalent technology. The Prop-Fan propulsion system is being investigated as part of the NASA Aircraft Energy Efficient Program. This effort includes the wind tunnel testing of a series of 8 and 10-blade Prop-Fan models incorporate swept blades. Test results indicate efficiency levels near the goal of 80 percent at Mach 0.8 cruise and an altitude of 10.67 km (35,000 ft). Each successive swept model has shown improved efficiency relative to the straight blade model. The fourth model, with 45 deg swept blades reported herein, shows a net efficiency of 78.2 at the design point with a power loading of 301 kW/sq meter and a tip speed of 243.8 m/sec (800 ft/sec.).

Installation for charging a pressure reservoir provided as a pressure source within a propulsion control system of a motor vehicle

Abstract: In a vehicle equipped with a propulsion control system combined with an anti-blocking system, a pressure reservoir provided as a brake pressure supply-source which can be charged by means of the return pump of the anti-blocking system, whereby the charging operation is valve-controlled so that the feed from the return pump is directed into the pressure reservoir during pressure-reduction phases of the propulsion control system, the pressure reservoir can also be charged, outside the control phases of the propulsion control system, either by operating the driver's brake pedal or by automatic activation of a charging circuit accompanied by the operation of the return pump.

Transfer vehicle for use in conjunction with a reusable space shuttle

Abstract: A spacecraft or transfer vehicle for transportation of a payload from a space shuttle parking orbit to a higher operation orbit, wherein the transfer vehicle utilizes housekeeping subsystems integrated into the payload, to avoid unnecessary duplication of these subsystems, for such functions as power supply, guidance, control, and communications. The transfer vehicle disclosed includes a propulsion system with at least one low-thrust bipropellant liquid rocket engine, to provide a "soft" or low-acceleration ascent, and employs two tanking stages, each having four propellant tanks, arranged symmetrically in a circular configuration. The first stage of four tanks is jettisoned during ascent, and the second stage, including the remaining four tanks, the rocket engine, and related supporting structure, is separated from the payload when the operational orbit is reached.

Marine propulsion system

Abstract: A propulsion transmission for a ship having a reversibly driven propeller shaft with a fixed pitch propeller and a torque converter of the single stage and fixed housing type for driving the propeller in the reverse direction. A planetary gear system is provided for driving the ship in a forward direction and a disengageable friction plate type brake is connected between the transmission housing and the planetary gear system and for forward drive. The brake is engaged to anchor a portion of the planetary gear system to drive said propeller shaft in a forward direction. The brake is disengaged when the torque converter is driving the propeller shaft in the reverse direction. One embodiment of the invention also includes a friction plate type clutch connected between the planetary gear system and the propeller shaft for transmitting power to the propeller shaft in a forward direction when the brake is disengaged. The clutch and brake are concentrically located with respect to one another in an axially compact arrangement.

Intestinal wall motion, propulsion, and fluid movement: trends toward a unified theory.

Abstract: WEEMS, WILLIAM A. Intestinal wall motion, propulsion, and fluid movement: trends toward a unified theory. Am. J* Physiol. 243 (Gastrointest. Liver Physiol. 6): G177-G188, 1982.-Research in the field of intestinal motility has progressed to the stage where a formal theory is needed to account for the production and control of fluid motion within the intestinal lumen. Because significant advances toward the development of such a theory require that investigators design their experiments with this specific goal in mind, an initial framework of concepts is proposed to aid in the development of a unified theory of motility. Intestinal motility is viewed as having three aspects: wall motion, propulsion, and fluid movement. The temporal and spatial behavior of any single aspect is not autonomous in origin or caused solely by the behavior of one of the other aspects. The behavior of each emerges from ongoing interactions among all three aspects. Each aspect is discussed both as a separate entity and in terms of the interactions known or expected to occur between or among these aspects. Specific problems associated with traditional approaches used to individually study each aspect are considered. These include difficulties in quantitatively describing wall and fluid motions and in determining the causes of wall motions. Methods currently being used and those suspected of having value in studying interactions among the three aspects of motility are also discussed. The conceptual framework and methods of experimentation advocated in this paper contribute only to the initial stage of a longterm development effort that will require years of research to formulate a theory that integrates wall motion, propulsion, and fluid movement. Further development of a unified theory of motility will depend heavily on the continued modification and application of experimental techniques and conceptual tools borrowed from such fields as systems engineering, fluid mechanics, mathematics, and computer science.

Method and apparatus for safely controlling explosions in black liquor recovery boilers

Abstract: Apparatus and method is disclosed for monitoring black liquor recovery boilers to detect the presence of water leakage into the combustion chamber (furnace) of a black liquor recovery boiler, or extinguishing of flame at the black liquor spray nozzles, to release into the furnace at a relatively high rate of speed an absorption agent to collect the water in the furnace and thereby isolate the water from the smelt, and further to provide a medium from which the water may be evaporated to expedite cooling within the furnace without risk of a water/smelt explosive reaction. The apparatus includes propulsion devices for distributing the absorption agent over the furnace smelt, which propulsion devices are controlled by sensors respectively detecting boiler steam pressure, water pressure, and combustion flame. Manual actuation of the propulsion devices is also contemplated by the invention.

Torsional mode suppressor

Abstract: Damping of a helicopter rotor drive train, the drive train including the free turbines of a gas turbine engine propulsion system, the aircraft main and tail rotors, and associated shafts and gears, is accomplished through active modulation of the fuel flow to the engine gas generator. The fuel flow is varied such that a transient torque will be developed by the free turbines which is opposite in phase to drive train resonances.

NASA's laser-propulsion project

Abstract: Design concepts, study results, and research directions toward development of CW laser heating of remotely flying spacecraft fuels to provide high impulse thrust are presented. The incident laser radiation would be absorbed by hydrogen through a medium of a laser-supported plasma. The laser energy could be furnished from an orbiting solar-powered laser platform and used to drive the engines of an orbital transfer vehicle (OTV) at costs less than with a chemical propulsion system. The OTV propulsion chamber would be reduced in size comparable to the volume addition of the incident laser energy absorber. The temperatures in the hydrogen-fueled system could reach 5000-15,000 K, and studies have been done to examine the feasibility of ion-electron recombination. Kinetic performance, temperature field, and power necessary to sustain a laser thrust augmented system modeling results are discussed, along with near-term 30 kW CO2 laser system tests.

Control system for torque correcting device

Abstract: This invention provides a marine propulsion device comprising a propulsion unit, a transom bracket adapted to be fixedly connected to a boat transom and a swivel bracket mounted on the transom bracket for pivotal movement about an axis which is horizontal when the transom bracket is boat mounted. The marine propulsion device also includes a king pin assembly mounted on the swivel bracket for pivotal steering movement of the propulsion unit and a mounting mechanism for mounting the propulsion unit on the king pin assembly and permitting limited rotational movement of the propulsion unit relative to the king pin assembly. The marine propulsion device also includes a trim tab mounted on the propulsion unit for pivotal movement about an axis transverse to the horizontal axis, and a linkage mechanism for displacing the trim tab about the transverse axis in response to rotational movement of the propulsion unit relative to the king pin assembly.

Compact drive assembly

Abstract: A drive system for a tracked vehicle includes a composite transmission having a primary transmission unit and a secondary transmission unit which is driven by components of the primary transmission unit. The primary transmission unit includes a propulsion gear and a steering gear both of which are driven from an engine drive shaft. The secondary transmission unit includes a pair of planetary gear sets which drive a pair of output wheels, tracks or chains of the vehicle. In order to conserve space, the transmission is configured such that the propulsion gear and the steering gear are positioned alongside the engine adjacent the drive shaft end of the engine and the secondary transmission components extend in front of the drive shaft end of the engine with a portion of each planetary gear set projecting alongside the engine. In an alternate embodiment, the propulsion gear and steering gear are positioned alongside the engine adjacent the drive shaft end while the secondary transmission components are positioned adjacent the opposite end of the engine.

Introduction to Vehicle Dynamics

Abstract: Today’s and tomorrow’s vehicles are based on various principles and travel with very different speeds. For a first classification of all kinds of vehicles the support and propulsion principles are used. The support mechanism has to balance the gravity acting on vehicles and the propulsion generates the forward speed, Fig. 1.

Selectively disengageable, tiller actuated vane steering system

Abstract: A steering system for a marine drive having a propulsion unit pivotally mounted on the transom of a watercraft and a tiller. The steering system includes a steering vane rotatably mounted on the propulsion unit for generating hydrodynamic forces to pivot or assist in pivoting the propulsion unit and to counteract propeller torque. A mount interposed between the propulsion unit and the tiller mounts the tiller for movement relative to the propulsion unit. A cable connects the tiller to the steering vane so that movement of the tiller with respect to the propulsion unit rotates the vane. The mount includes mutually engageable elements that can lock the tiller against movement relative to the propulsion unit so that the tiller may be used to directly steer the propulsion unit, if desired. For this purpose, the elements of the mount may be engaged by applying a downward pressure on the tiller.

A concept for light-powered flight

Abstract: The concept for an advanced flight transport vehicle propelled by variable cycle laser propulsion engines is described. The vehicle is designed for efficient propulsion both within the atmosphere (by momentum exchange) and in space (as a rocket). Pulsed laser power is absorbed directly into gaseous reaction propellants by electrical gas breakdown and inverse Bremsstrahlung. Small scale experiments on each key engine component have been performed, and their performance characteristics are known. Innovation results from the synergism of the various engine parts. The resultant system can demonstrate substantial performance improvements over conventional chemical thrusters and flight vehicle configurations--in a future era of plentiful beamed space power.

Electric and hybrid vehicles

Abstract: The publication presents a number of papers which examine developments in the field of electric vehicle technology, and includes the following: Electric and Hybrid Vehicles: An Introduction (Lafferty, JM); What Technology will Solve the Mobility Problems of the Year 2000 and What Steps Must be Taken Today? (Seiffert, U, Heitland, H, Kalberlah, A and Heinzel, G); The Technical and Economic Effectiveness of Electric Vehicles (Brusaglino, G); Social and Environmental Impacts of Electric and Hybrid Vehicles (Hamilton, WF, Morecraft, LM and Carriere, WM); Computer-Aided Design of Electric and Hybrid Vehicles (Wilson, JWA and Turnbull, FG); Regeneration Potential of Electric Vehicles (Kuzak, DM, Patil, PB and Bates, B); Rebirth of the Lead-Acid Battery--Meeting the Electirc Vehicle Challenges of the 1980s (Mrotek, EN and Gurlusky, PJ); A Generic Battery Model for Electric and Hybrid Vehicle Simulation Performance Prediction (Chapman, P and Aston, M); A Systems Approach to the Aerodynamic Design of Electric and Hybrid Vehicles (Kurtz, DW); The Daihatsu Charade' Electric Vehicle (Honda, S); A Hybrid Electric Bus (Brusaglino, G). (TRRL)

Carrier for a dropload to be dropped from an aircraft

Abstract: A load such as supply containers, weapons or the like is dropped from an craft by a carrier which has a longitudinal support beam and wings which are hinged to the support beam to normally extend in the direction of the longitudinal support beam when the load is secured to the aircraft through the support beam. Once the beam with the load attached thereto is released from the aircraft the wings are automatically spread out for controlling the flight of the load to the ground. The longitudinal carrier or the load itself may be equipped with a propulsion system that may be controlled automatically by control means forming part of the load or it may be controlled by remote control.

Shaft brake for marine propulsion system

Abstract: A marine propulsion system for a water craft comprises a relatively large engine or power plant and a power transmission including an output shaft for driving the propeller. The power transmission includes forward and reverse shafts, gear trains between these shafts and the output shaft, and clutches for the forward and reverse shafts. A shaft brake is provided to stop rotation of the output shaft for the propeller which minimizes damaging shocks to the propulsion system which sometimes occur during maneuvering operations. The brake is located concentrically with the forward shaft of the power transmission and is effective to brake the propeller shaft through interconnecting gears when both clutches are disengaged.

Propulsion controller for automobile

Abstract: A system for controlling the propulsion on motor vehicles which not only enables the output torque of the drive unit of the vehicle to be utilized in an optimum manner in critical driving situations, especially under extreme road conditions, but also endows the vehicle with good stability and enhanced driving safety. A comparator is provided, in a propulsion control system which is triggered by at least one presettable or permanently preset threshold value of the speed of the vehicle, and generating an output signal causing the drive torque to be reduced, as soon as this threshold value is exceeded and a signal is present, which indicates that an individual wheel brake is being activated and/or that one of the driven wheels is tending to spin. The threshold value of the speed of the vehicle, which value governs the control process, is preferably regulated in accordance with the transverse acceleration which acts on the vehicle whenever it follows a curved path.

Main-belt asteroid exploration - Mission options for the 1990s

Abstract: Mission configurations, propulsion systems, and target bodies for possible NASA asteroid exploration projects are examined. Noting that an announced delay in the development of a solar electric propulsion system has led to a consideration of chemical rocket systems, asteroid missions are grouped in terms of five potential areas for investigation, each successively further from the sun. The Shuttle-launched IUS is suggested as the prime candidate for boosting probes into trajectories for asteroid rendezvous with a number of the 3000 known asteroids. Planetary swingbys are mentioned as the only suitable method for satisfying the large energy requirements of the asteroid missions. Performance analyses are presented of the IUS 2-stage/Star-48 and Centaur vehicles, and sample missions to Fortuna, Anahita, and Urania in 1990 and further missions to the middle, outer, and Trojans asteroids are outlined.

Resistojet propulsion for large spacecraft systems

Abstract: Resistojet propulsion systems have characteristics that are ideally suited for the on-orbit and primary propulsion requirements of large spacecraft systems. These characteristics which offer advantages over other forms of propulsion are reviewed and presented. The feasibility of resistojets were demonstrated in space whereas only a limited number of ground life tests were performed. The major technology issues associated with these ground tests are evaluated. The past performance of resistojets is summarized and, looks into the present day technology status is reviewed. The material criteria, along with possible concepts, needed to attain high performance resistojets are presented.

Compound propulsion unit comprising heat engines working on different principles

Abstract: The invention relates to a compound propulsion unit consisting of any heat engines working on different principles, preferably a spark- ignition engine and a Stirling engine. The heat from the spark- ignition engine is used to operate the Stirling engine. The spark- ignition engine and the Stirling engine may be accommodated either in a common housing or in two separate housings and their output energies given off via a collective drive output or two separate drive outputs. Compound propulsion units may also be so designed that a plurality of component engines are used in different numbers in each case. The compound propulsion unit improves the efficiency of conventional heat engines and is particularly suitable for constant or slightly varying modes of operation such as, for example, current generators, ship propulsion and locomotive propulsions.