Showing papers on "Turbine published in 1979"

A Vortex Model of the Darrieus Turbine: An Analytical and Experimental Study

Abstract: A preliminary aerodynamic performance prediction model has been constructed for the Darrieus turbine using a vortex lattice method of analysis. A series of experiments were conducted for the express purpose of validating the analytical model. These experiments were conducted on a series of two dimensional rotor configurations which were towed in a large tank of water. The use of water as a working fluid was intended to facilitate both flow visualization and the ability to measure aerodynamic blade forces while allowing operation at sufficiently high Reynolds numbers. The primary purpose of this research was to allow reasonable predictions of aerodynamic blade forces and moments to be made.

Energy Effectiveness of Arbitrary Arrays of Wind Turbines

Abstract: Determination of power degradation due to interference between wind turbines in an array is of importance in the engineering and economic planning of wind farms. A computer model for an arbitrary array of turbines is described. The basic fluid mechanics are treated in a simple but rational way. The turbine wake expands downstream due to ambient turbulence and mechanically generated turbulence (caused by momentum gradients) and entrains momentum and mass. Drag or momentum deficit, though, is conserved. Ground effect is handled by imaging. The effect of ambient turbulence is shown to be much greater than of that due to the momentum deficit generated by the turbine. The basic equations use fundamental fluid mechanical expressions related to drag conservation and wake growth due to turbulent entrainment and a family of self-similar wake profiles derived from experiment. This approach fully defines the wake velocity field. The wake of each turbine is then determined, subject to all upstream interferences. Power outputs of selected arrays as functions of wind direction are presented. The model is very well supported by the limited data available, and has proven effective and easy to implement. Advanced models incorporating nonuniformities in wind and turbulence and tower shadow are also described.

Fluid dynamic aspects of wind energy conversion

Abstract: : A review is made of the fluid dynamic aspects of wind energy conversion. A short survey of the total framework of wind energy conversion is given to bring the fluid dynamics aspect in its proper dimensions. Next, the several wind concentrator concepts are discussed, while the main body of the report is formed by a discussion of the theory of wind-driven turbines, including both the horizontal-axis and the vertical-axis turbines. The report concludes with a survey of inhomogeneous flow and turbulence effects, turbine control and wake interference effects.

Differential geared engine

Abstract: A gas turbine engine comprising a fan, a compressor and a turbine, wherein the torque requirements of the fan or compressor can be modulated, is provided with differential gearing to transmit all of the fan and compressor power requirements from the turbine. The differential gearing maintains an adjustable speed relationship between the fan and compressor with respect to the turbine depending upon the torque requirements thereof and the gear ratios within the differential gearing.

Multi-mode control system for wind turbines

Abstract: A multi-mode electronic wind turbine control system establishes a reference blade angle for a two-bladed, horizontal axis, variable pitch wind turbine rotor, the blade angle being regulated by a hydraulic pitch change mechanism. The rotor, via appropriate shafts and a gearbox, is coupled to a synchronous generator to produce electrical energy which is fed to a power utility grid. The control system provides closed loop pitch control for rotor acceleration rate during start-up, for rotor deceleration rate during shutdown, for speed control when the synchronous generator is off-line, and for power control when the synchronous generator is on-line. A single control integrator is used for all closed loop operating modes, with a rate limiter circuit in front of the control integrator to prevent integrator overtravel. The integrator has maximum and minimum blade angle stops, the minimum stop being variable as a function of rotor speed and wind speed. When on-line, power control is provided by a unique shaft torque control using proportional plus integral plus derivative controls in combination.

Power plant for camping trailer

Abstract: A power plant for mobile homes, camping trailers, and the like, capable of capturing low powered aeolian energy, storing said energy in the form of compressed air, and delivering it on demand in the form of household electrical current. The device comprises a wind turbine driving an air compressor which feeds a storage tank. On demand, the compressed air drives a turbine coupled to an electrical generator. Various pressure regulators are used to regulate the speed of the generator. The wind turbine is also coupled to an alternator which maintains a bank of electrical batteries charged. A DC motor running on the batteries is used when necessary to boost the drive of the air compressor during periods of heavy or long power drain. Provision is made for rapidly recharging the power plant from either a supply of compressed air or from an AC power source.

Directly driven dynamo electric machine-gas turbine generator structure

Abstract: The rotor of a generator for automotive internal combustion engine turbo-superchargers is located on the turbine shaft to rotate therewith, at the turbine speeds of between 20,000 rpm to 80,000 rpm, and positioned between the exhaust gas turbine blade unit and the supercharger-compressor blade unit. The rotor, preferably, is a permanent magnet rotor, cooperating with stationery armature structures which may have different, separate windings thereon to supply different networks at independently selected voltages, for example a vehicular battery through a rectifier network and heating elements, in single-phase and three-phase connections, as desired, such as windshield heaters and the like, which can be directly a-c energized. The generator may have an axial air gap and may be cooled by a compressed air bleeder duct formed in the compressor blade unit.

System and method for accelerating and sequencing industrial gas turbine apparatus and gas turbine electric power plants preferably with a digital computer control system

Abstract: A gas turbine power plant is provided with an industrial gas turbine which drives a rotating brushless exciter generator coupled to a power system through a breaker. One or more of the turbine-generator plants are operated by a hybrid digital computer control system during sequenced startup, synchronizing, load, and shutdown operations. The program system for the computer and external analog circuitry operate in a multiple gas turbine control loop arrangement. Logic macro instructions are employed in programming the computer for logic operations of the control system.

Energy effectiveness of arbitrary arrays of wind turbines

Abstract: Determination of power degradation due to interference between wind turbines in an array is of importance in the engineering and economic planning of wind farms. A computer model for an arbitrary array of turbines is described. The basic fluid mechanics are treated in a simple but rational way. The turbine wake expands downstream due to ambient turbulence and mechanically generated turbulence (caused by momentum gradients) and entrains momentum and mass. Drag or momentum deficit, though, is conserved. Ground effect is handled by imaging. The effect of ambient turbulence is shown to be much greater than of that due to the momentum deficit generated by the turbine. The basic equations use fundamental fluid mechanical expressions related to drag conservation and wake growth due to turbulent entrainment and a family of self-similar wake profiles derived from experiment. This approach fully defines the wake velocity field. The wake of each turbine is then determined, subject to all upstream interferences. Power outputs of selected arrays as functions of wind direction are presented. The model is very well supported by the limited data available, and has proven effective and easy to implement. Advanced models incorporating nonuniformities in wind and turbulence and tower shadow are also described.

Vertical axis wind turbine for generating usable energy

Abstract: A wind turbine for converting wind forces into usable energy has a main shaft rotatably mounted in the axis of rotation for the wind turbine, and a pair of coacting complementary longitudinally extending vane members are connected to each other by a plurality of support and transmission assemblies in the form of articulated members and to the main or driven shaft for driving engagement thereof. The coacting vane members may either have straight side edges or preferably have spiralled or helically shaped side edges which in the closed position are aligned and in abutment with each other to define and form a right circular cylinder in side elevation. The vanes are movable between a normally open starting position and a closed position to vary the total vane surface available for contact by the wind forces acting at any given time when the wind turbine is in operation. Articulated members of the support and transmission assemblies are pivoted to permit translational or side wise movement to and fro of the complementary vanes transverse relative to each other and the vertical axis through the main shaft, and pivotal cross members on each of the articulated support and transmission assemblies are vertically linked together to simultaneously alter the articulated members during such movement. The respective complementary and cooperating vanes have their weight so distributed that centrifugal forces will act to move the complementary vanes towards the closed or right circular cylindrical form automatically as high rotational speeds result from excessive wind. Additionally the wind turbine as above described with resilient means to move the coacting cooperating vanes to the normally open starting position.

Turbine cooling air modulation apparatus

Abstract: The cooling air flowpath for a turbomachine includes a plurality of valves placed in mutually parallel relationship to collectively provide for the modulation of the cooling airflow. Minimum flow requirements are assured while economizing on air to increase efficiency. Any single valve passes only a small portion of the total air so that a valve failure does not appreciably reduce the overall cooling function.

Air ejector augmented compressed air energy storage system

Abstract: Energy is stored in slack demand periods by charging a plurality of underground reservoirs with air to the same peak storage pressure, during peak demand periods throttling the air from one storage reservoir into a gas turbine system at a constant inlet pressure until the air pressure in the reservoir falls to said constant inlet pressure, thereupon permitting air in a second reservoir to flow into said gas turbine system while drawing air from the first reservoir through a variable geometry air ejector and adjusting said variable geometry air ejector, said air flow being essentially at the constant inlet pressure of the gas turbine system.

Combined gas turbine-rankine turbine power plant

Abstract: A combined gas turbine-Rankine cycle powerplant with improved part load efficiency is disclosed. The powerplant has a gas turbine with an organic fluid Rankine bottoming cycle which features an inter-cycle regenerator acting between the superheated vapor leaving the Rankine turbine and the compressor inlet air. The regenerator is used selectively as engine power level is reduced below maximum rated power.

Turbocharger and adaptations thereof

Abstract: Turbocharger (20), compressor (170) and turbine (172) rotors mounted on a shaft (160) supported by ball bearing assemblies (162, 164) such that the compressor rotor (172) and turbine rotor (170) are overhung to one side of the bearing assemblies with the turbine rotor separated from the bearing assemblies by the compressor rotor. The turbocharger (20) includes a turbine nozzle area (230) having a plurality of nozzle vanes (234) spaced circumferentially about the turbine rotor and in the nozzle area through which exhaust air from the engine is received into the turbine. A control linkage (228) is positioned intermediate of the compressor rotor and turbine rotor and controls the position of the nozzle vanes to vary the flow of exhaust gases to the turbine rotor. A concentrically positioned cylindrical module (60) is supported within the compressor inlet by struts (62) extending from the inlet wall (64) to the module (60) thereby dividing the inlet into more than one inlet passage. In one embodiment of the invention, a second compressor rotor (450) is mounted on the shaft (160) in the compressor rotor (172). In other embodiments of the invention, the turbocharger (20) is modified to function as a turbojet (500, 750) and as a turbofan (650).

Electrical power generating system

Abstract: A geothermal energy system in which a bore hole is drilled into the earth to a depth where a predetermined temperature gradient exists between the earth's surface and the bottom of said bore hole. A liquid refrigerant line passes down the bore hole and connects to an evaporator where the geothermal energy is used to vaporize the refrigerant and from there it passes back up through a high pressure gaseous refrigerant return line to a gas operated turbine located at the earth's surface. The spent refrigerant exiting from the turbine is cooled in a condensing unit and recirculated to the subterranean evaporator unit. The turbine may be used to drive a suitable electrical generator for power production purposes.

Variable clearance control for a gas turbine engine

Abstract: Clearance control between an outer air seal of a gas turbine engine and an internal, turbine section of the engine is controlled by selectively modulating a cooling air supply that is directed to selected portions of the air seal supporting structure to control its thermal growth. Impingement of the cooling air causes contraction of the seal structure, thereby lessening the clearance for the purpose of improving engine performance. The flow of cooling air is modulated in response to engine speed and engine altitude to maintain relatively low clearance during critical periods of engine operation.

Electricity generation from jet-stream winds

Abstract: The feasibility of generating electricity from jet-stream winds has been investigated. Analysis of published meteorological data indicates that annual average power densities approaching 20 kW/m2 are available in the jet-stream altitudes over the complete west-east extent of Australia at a latitude of about 30° S. Computer-based optimization studies indicate that a 100 MW power station based on tethered aerodynamic generating platforms located at a jet-stream altitude would generate electricity at capital and operating costs that are competitive with other methods of electricity generation. The design of the tethered aerodynamic generating platform requires a high lift-to-weight ratio platform housing high power-to-weight ratio diffuser-augmented wind turbines and tethered by a high strength-to-weight ratio cable. Key design parameters include the turbine power coefficient and power-drag coefficient, the rated speed, and the stall speed. The required turbine area is determined primarily by the power coefficient and the rated speed. The cable weight depends directly on the drag associated with the maximum (rated) power generation which follows from the choice of rated speed. The wing area of the aerodynamic platform is fixed usually by the stall speed.

Free wing turbine

Abstract: Apparatus to convert wind energy into mechanical and electrical energy including a variable pitch air-foil supported by tension guy wires on a wheeled structure constrained to move upon a continuous track. The structure includes electrical generators powered by the rotation of the structure's wheels to convert movement of the structure into electrical energy. The air-foil is supported upright on the wheeled structure, which is designed to resist upward, downward and sideways forces, to capture wind energy at a higher elevation above the ground where winds blow stronger.

Multi-stage, wet steam turbine

Abstract: A multi-stage, wet steam turbine employs working fluid, such as steam for example, in its two-phase region with vapor and liquid occurring simultaneously for at least part of the cycle, in particular the nozzle expansion. A smaller number of stages than usual is made possible, and the turbine may handle liquid only. Simple construction, low fuel consumption and high reliability are achieved.

Gas turbine cooling systems

Abstract: A gas turbine engine having a turbine with internally cooled, stationary nozzles incorporated into first and second stage nozzle segments and a system for supplying air to the nozzles, for effecting a flow of cooling air into impingement and film cooling relationships with a tip shoe mounted in the nozzle case, and for generating a flow of air which first impingement cools a nozzle case lip supporting the upstream ends of the second stage nozzle segments and then acts as a buffer, keeping hot gases from entering the space between the nozzles and the nozzle case.

Experimental Demonstration of the Diff user-Augmented Wind Turbine Concept

Abstract: The surface area requirements of an efficient diffuser has been reduced by innovative use of the external wind to produce a cost-effective wind energy conversion system (WECS). Three sets of tests were conducted on very compact diffusers: 1) on small-scale models using screens to simulate a real turbine; 2) on ten times larger scale models with screens; and 3) on a real turbine. The first-generation nonoptimized diffuser-augmented wind turbine (DAWT) configuration is a conical, 60 deg included angle diffuser with an area ratio of 2.78 controlled by two tangential injection slots for boundary-layer control. This baseline model provided over three times the power of a conventional WECS with the same turbine efficiency, diameter, and free wind. An optimized configuration should provide augmentations greater than four.

Air-powered vacuum cleaner floor tool

Abstract: A vacuum cleaner floor tool is provided which comprises a housing formed by upper and lower members which mate with one another along a single plane inclined with respect to the base plane or bottom of the lower member. An air-powered turbine motor is positioned in the housing and includes a turbine chamber for the turbine motor, and a rotary floor agitator is provided which partially extends from the housing. The agitator is coupled to the turbine motor and is driven thereby. A base plate is removably mounted on the housing and forms a portion of a wall thereof, with the agitator extending from the housing through an opening in the base plate. Air passes through the opening in the base plate into the turbine chamber. The base plate includes a ramp which extends from the base plate into the housing, where the ramp and a portion of the turbine chamber form a nozzle for the turbine motor.

Exhaust pipe of turbine

Abstract: The exhaust pipe of a turbine accommodates in the inner portion (3) thereof a guide (8). The inner side surface of the guide (8) is essentially the surface of a body of revolution about an axis coincident with the axis (6) of the turbine. The guide (8) is disposed so that one of its ends (9) adjoins the outer ends (10) of the blades (4) of the runner (5) of the turbine. In accordance with the invention, the guide (8) is adapted to vary the area of the flow cross-section of the inlet portion (3) of the exhaust pipe.

Water and steam injection system for emission control of gas turbines

Abstract: A control system for the injection of water or steam into the combustion chambers of a combustion turbine for reducing the emission of oxides of nitrogen in the exhaust gas of a combustion turbine is described. The control system includes a water control valve having a linear flow versus stroke characteristic which is controlled by an error signal representing the difference between a predetermined water-to-fuel schedule and the actual water-to-fuel schedule. Instruments for monitoring and recording water and fuel flow are also described.

Counter-rotating wave energy conversion turbine

Abstract: A counter-rotating turbine for converting energy from waves. A turbine is positioned in a pneumatic-type wave energy converter and converts the energy of alternating air flow above the internal water surface into mechanical energy. The turbine has counter-rotating runners and guide vanes located both upstream and downstream, and the alternating air flow in the energy converter excites the turbine runners after being turned by the guide vanes.

Method of and apparatus for the cooling of natural gas

Abstract: A method of cooling natural gas in a system in which the natural gas contains components other than methane which are separable by dewpoint condensation and the natural gas is available from a source, e.g. a well, at an elevated pressure. In accordance with the present invention, the natural gas is initially expanded in a work-producing expansion turbine to cool the natural gas to a temperature below the dew point of the components to be separated and the portion of the natural gas remaining after separating these components is compressed in a compressor which can in part be driven by the turbine so that at least a portion of the work output of the turbine is at least in some cases utilized for compressing the methane-containing portion which can be forced under pressure into a pipeline. In dependence upon the variable pressure difference between the input of the expansion turbine and the output of the compressor, energy is recovered from the turbine or supplied to the set formed by the turbine and compressor and the compression of the expanded methane-containing portion is effected after heat exchange with the natural gas to be expanded and/or is directly carried out at the expansion temperature.

Wind turbine of cross-flow type

Abstract: Wind turbine of cross-flow type with constant or cyclically adjustable blade angle. The vanes (2) consist of one or more sets of blades with arched or, in sections, straight extension in longitudinal direction, comprising several substantially parallelly extending blades (3, 4 8), the spacing of which from one another is fixed by means of a number of spacing elements (5, 9) having aerodynamic profiling and providing a spacing of the order of magnitude of between 1/2 and 3 times the blade chord.

Air cooled turbine for a gas turbine engine

Abstract: An air cooled turbine which has cooling air provided through pre-swirl nozzles into an annulus formed between radially inner and outer seals and then into cooling air inlets to the turbine blading, has leakage air deflector means to prevent the leakage flow from the inner to outer seal interfering with the cooling air flow. The deflector means may comprise leakage flow inlets adjacent the inner seal, channels extending radially and cooperating with the turbine rotor to provide passages for the leakage flow to a location radially outboard of the cooling air inlets to the turbine blading, and open portions through which the cooling air can flow to the cooling air inlets. The channel outlets of the deflector may be arranged so that some of the leakage flow can be directed to cool a less critical part of the turbine blading the remaining leakage flow being directed radially outboard of the cooling air inlets to a more critical part of the turbine blading which are arranged to receive the normal cooling air flow.

Utilization of solar energy

Abstract: Solar energy is utilized to convert water into steam for use in driving a turbine which, in turn, is used to generate electricity. At the same time air in a solar panel is utilized to drive another turbine which in turn generates electricity. The water recovered by condensation of the steam is permitted to drop from the elevation at which it is accumulated and that water is used to drive another turbine which in turn generates further electricity.