Showing papers on "Gas compressor published in 1982"

Internal combustion engine with an exhaust gas turbocharger

Abstract: In the operation of supercharged internal combustion engines, certain operating conditions exist during which the exhaust gas turbochargers cannot supply adequate supercharging air for the internal combustion engine due to a low production of exhaust gas by the engine To eliminate this problem, an auxiliary compressor with a flywheel is proposed, which is constantly driven by an auxiliary drive mechanism and whose power input can be considerably reduced by closing its air conduit In case of lacking charging air, the auxiliary compressor is used in a simple way, by opening the closure devices on its air side, in order to enable a supply of supercharging air to the internal combustion engine The power required for driving the auxiliary compressor is derived primarily from energy stored in the revolving flywheel mass as well as from the power of the auxiliary drive mechanism

Specific coefficient of performance measuring device

Abstract: By measuring the power supplied to a compressor motor and by measuring four temperatures within a mechanical vapor-compression system, it is possible to develop a device for measuring and/or displaying the specific coefficient of performance of the mechanical vapor-compression system. The use of the temperatures and power supplied to the compressor motor can be used with information on motor losses and a typical temperature-enthalpy and a typical pressure-entropy diagram to allow substantially instantaneous computation of the actual specific coefficient of performance of a mechanical vapor-compression system as it operates. The measuring device can usually be installed totally external to a building in which the mechanical vapor-compression system is being used as a cooling system, or as a heat pump for heating and cooling.

Variable displacement compressor control valve arrangement

Abstract: There is disclosed in a refrigerant compressor whose displacement is controlled by crankcase-suction pressure differential, a control valve arrangement which is responsive to both compressor suction and discharge pressures to provide controlled communication of same with the compressor crankcase so that the compressor displacement and thereby the discharge flow rate is caused to increase with increasing discharge pressure as well as with increasing suction pressure.

Compressor bleed air control apparatus and methods

Abstract: A turbine engine accessory power unit has a compressor bleed air control system in which a surge bleed valve is proportionally and integrally controlled to maintain a constant minimum compressor bleed flow rate slightly above the compressor's surge flow rate. The system control parameter is automatically reset as a function of the position of the compressor's adjustable inlet guide vanes to assure optimum control system performance throughout the air delivery range of the compressor.

Stirling cycle cryogenic cooler

Abstract: A long lifetime Stirling cycle cryogenic cooler particularly adapted for space applications comprised of a compressor section (10) centrally aligned end to end with an expansion section (12) and respectively including a reciprocating compressor piston (14) and displacer (16) radially suspended in interconnecting cylindrical housings (18, 20) by active magnetic bearings (26, 28, 30, 32) and having adjacent reduced clearance regions (82, 84, 108) so as to be in non-contacting relationship therewith and wherein one or more of these regions operate as clearance seals. The piston (14) and displacer (16) are reciprocated in their housings (18, 20) by linear drive motors (48, 52) to vary the volume of respectively adjacent compression and expansion spaces (44, 46) which contain a gaseous working fluid and a thermal regenerator (95) to effect Stirling cycle cryogenic cooling. Electrical circuit means (140, 142) are additionally included for energizing the magnetic bearings (26, 28, 30, 32) and for controlling the stroke amplitudes and relative phase angle between the compressor piston (14) and displacer (16) during the cooling cycle.

An Investigation of Axial Compressor Rotor Aerodynamics

Abstract: The detailed nature of the three-dimensional flow over the blading, and in the wake, of an isolated compressor rotor has been studied experimentally in a large scale rotating rig. A variety of flow properties were measured including (1) blade profile and endwall surface flow visualization. (2) radial-circumferential arrays of pneumatic wake data acquired in the rotating frame and (3) full-span blade pressure distribution data. 23 refs.

Turbojet with contrarotating wheels

Abstract: A turbojet having a multistage axial compressor with contrarotating blade wheels fitted on inner and outer contrarotating rotors driven in opposite directions by respective turbine wheels. Each blade wheel (105) of the outer compressor rotor is associated with a rotating shell (86, 81, 82) having relatively few thick spokes for transmitting the drive from the turbine wheel, thereby leaving the blades to transmit aerodynamically induced forces only.

Gas turbine engine cooling airflow modulator

Abstract: The invention is a cooling airflow modulation system for use on gas turbine engines. The system utilizes one or more circumferential manifolds for collecting and providing a source of high-pressure cooling air to hot turbine parts. The cooling air is directed to the manifolds through valved passageways that collect compressor discharge air and direct that air radially inwardly and axially downstream to manifold locations. Multiple passageways aand manifolds provide a means for maintaining pressure in the hot turbine parts while cooling airflow volume is being modulated through selected manifold and passageway combinations.

Solid state clutch cycler with charge protection

Abstract: A solid state circuit for cycling the refrigerant compressor of an automotive air conditioning system on and off in accordance with a refrigerant vapor condition and for detecting the duration of compressor energization periods as an indication of low refrigerant charge. If a condition of low refrigerant charge is detected, the compressor is disabled and an instrument panel lamp is lit to notify the operator of the vehicle of the low refrigerant charge condition.

Regenerative gas turbine cycle

Abstract: In a regenerative gas turbine cycle in which heat recovery is carried out by a mixture of air/steam which is obtained by contact between water and a part of or the whole of compressed air, said compressed air being compressed by a compressor for compressing gas using air or air based gas as a combustion supporting/working medium gas; the improvement comprising: the mixture of air/steam and liquid phase cooled water being obtained through the contact between the compressed air and heated water which is used as heat recovering medium; said cooled water being used as heat recovering medium not only for heat recovery of turbine exhaust gas but also, for (a) intercooling of the compressor, and/or (b) precooling of compressed air for the contact operation; supplying water corresponding to the amount of water which contacts the compressed air and is lost by evaporation to the liquid phase water for contact or heat recovery as it is or after using as a heat recovering medium.

Air temperature control system for vehicles

Abstract: An air cooling temperature control system for use in vehicles including a cooler having a compressor, a heater having an air-mix damper and a room air temperature regulator, in which feedback control is effected so that a room air temperature may coincide with a preset temperature value. The output of the heater is regulated to respond to sudden changes in the room air temperature by controlling the opening of the air-mix damper. The duty cycle of the compressor is regulated by a controller so as to respond to gradual changes in room air temperature while the output of the heater is at a low level and to incrementally decrease the duty cycle of the compressor when the output of the heater is above the low level, thereby driving the output of the heater down so as to minimize the counteracting effects of concurrent heating and cooling, so that the desired room air temperature is maintained with minimal energy.

Energy efficient ECS powered by a variable voltage/variable frequency power system

Abstract: The invention is an ECS system designed to utilize an induction motor (12) and a cabin compressor (14) for providing pressurized air that serves as a source of energy for heating, cooling, pressurizing and other air needs of modern aircraft. An aircraft engine driven generator, preferably a permanent-magnet generator (of the samarium-cobalt, SmCo, type), furnishes variable-voltage/variable frequency, VV/VF, power to the motor (12). The electric motor itself in the preferred embodiment is a highly reliable squirrel-cage induction motor (12) powered directly from the VV/VF supply, with the result that its speed is proportional to the generator frequency, which in turn is dependent on the aircraft engine speed. The main cabin compressor (14) and a secondary (auxiliary) supercharging compressor (18) are both mounted on the motor shaft. The motor-compressor configuration is further characterized in that the ac motor has pole-changing winding (typically two), which permits two speed operation, while the cabin compressor is provided with inlet guide vanes (16). The interactive combination of these two features makes it possible to furnish the requisite air mass flow and pressurization levels over the conditions of variable air density and variable atmospheric pressure, as the airplane operates throughout its flight envelope.

Sealing system for a turboexpander compressor

Abstract: A turboexpander compressor for use in a gas processing system has a seal system that avoids communication of gas with the oil being pumped through the bearings. The device has a shaft carried in a housing on bearings with a compressor wheel on one side and an expander wheel on the other side. Labyrinth seals seal the wheels from the interior of the housing and the bearings. Mechanical seals are located between the bearings and the labyrinth seals for preventing leakage of oil. The mechanical seals are located in a drainage chamber that allows any oil or gas leaked past the seals to be drained from the system, rather than dilute the oil. Gas is injected from the compressor discharge into a groove on the expander side of the shaft to provide a thermal barrier. The mechanical seals each have a rotating ring carried by the shaft and a nonrotating ring carried by the housing. The nonrotating ring is biased into the rotating ring by means of an O-ring. The O-ring is located in a groove in the bore and a recess formed in the nonrotating ring. The recess is offset to deform the ring and cause it to exert a force on the nonrotating ring against the rotating ring.

Supply and protection unit for a hermetic compressor

Abstract: A supply and protection unit for a hermetic compressor of a thermostatically regulated refrigerator comprising an electrically insulating support body (3) adapted to be fixed to the casing of the compressor (P); said support body being provided with cavities (3a, 3b, 3c, 3d and 3e) opening at one of its faces intended to face towards the compressor for slidably and removably inserting therein of a pair of electrical devices (1, 2) and connection means thereof to be supported against the compressor casing, one of said devices being a thermally operated protection switch (1) and the other being a resistor (2) with a positive temperature coefficient.

A control circuit for a variable displacement air conditioning compressor

Abstract: A control circuit is disclosed for controlling the operation of a variable displacement device in an air conditioning compressor (10) in order to change the capacity of the compressor (10). The control circuit includes at least one solenoid (20) which controls the operation of one more valves in the variable displacement device. The solenoid (20) is connected to a voltage source (18) via a detecting device (21) which includes a pressure sensitive switch responsive to the pressure of the refrigerant in the air conditioning system at the inlet of the compressor (10). The detecting device (21) enables the solenoid (20) to decrease the capacity of the compressor (10) when the refrigerant pressure goes below a first predetermined pressure level and then disables the solenoid (20) when the refrigerant pressure exceeds a second predetermined level. The detecting device (21) also is responsive to the temperature of the refrigerant at the inlet of the compressor (10).

Vertical axis hermetic helical screw rotary compressor with discharge gas oil mist eliminator and dual transfer tube manifold for supplying liquid refrigerant and refrigerant vapor to the compression area

Abstract: A vertical axis hermetic compressor includes an inner cylindrical housing fixed internally of a sealed outer enclosure bearing paired helical screw rotors defining with the inner housing closed thread compressor compression chambers. An electrical drive motor overlies the rotors and is shaft connected to one of the rotors. Compressed refrigerant vapor, where refrigerant is the working fluid, discharges through the motor rotor. Centrifugal force functions as a primary oil separator for oil entrained within the working fluid. An inverted dish deflector underlies a gas discharge port axially within the top of the outer enclosure such that oil impacted by gas flow discharging axially from the motor adheres to the deflector to provide secondary oil separation while the gas passes about the periphery of the deflector to escape through the discharge opening of the outer enclosure. A non-woven plastic mesh pad fixed to the bottom of the deflector acts as a shock absorber for the entrained oil to prevent re-entraining oil in the gas stream in mist form to provide tertiary oil separation thereby reducing oil mist carried by the escaping gas to less than about 0.5 percent by weight. Oil dropping from the deflector into the bottom of the outer enclosure functioning as an oil sump impacts against a two passage parallel flow dual transfer tube including one passage supplying liquid refrigerant from the condenser to the compressor working space for cooling the same through a liquid injection port and within a second passage, intermediate pressure refrigerant vapor injected into the compression process through a vapor injection port. This prevents excessive heating of the working fluid pulsing in the tubes during compression with control valves in the passages leading to the liquid injection and vapor injection ports closed.

Integrated auxiliary power and environmental control unit

Abstract: An integrated auxiliary power unit and environmental control unit for an airplane 2, said integrated unit 2 comprising a prime mover 4, a variable geometry compressor 22 operable selectably by bleed air from the propulsion engine of said airplane or connectable via an overrunning clutch 18 to said prime mover, a controlled emission turbine 24 which is shaft-coupled to said compressor 22 and cooperating with said compressor to form an environmental control unit, and means for diverting a portion of the output of said compressor for use as an auxiliary power unit.

Isothermal positive displacement machinery

Abstract: In such machinery, e.g. a Stirling cycle heat pump, improved heat flow, and thereby thermal efficiency, is achieved by providing a large chamber wall area to chamber volume ratio through the use of bellows-like walls for the compression and expansion chambers 1 and 2. The gas chambers have movable end walls 4 and 5 which are reciprocated by connecting rods driven by cranks 6 and 7 on a motor-driven shaft 8. The machinery may instead consist of a positive displacement engine or a compressor. Significant gains in thermal efficiency, up to a factor of 2, are attainable because the largest inefficiency in all isothermal machinery is imperfect control of heat flow. A regenerator for extracting heat from and returning it to the gas in the chambers is preferably provided between the chambers 1 and 2. The regenerator minimizes cycle losses due to gas transfer friction, gas thermal conduction, dead volume, regenerator heat mass, regenerator heat mass thermal skin depth, and regenerator mass thermal conductivity in the gas flow direction.

A variable inlet area turbine

Abstract: A turbocharger for a diesel engine 34, wherein combustion air is supplied under pressure to the engine's intake manifold 32 from a centrifugal compressor 20 rotated by a turbine wheel 18 driven by exhaust gas from the engine supplied to inlet volute 44. Exhaust gas from the volute impinges on the turbine wheel after passing between stationary vanes 60 in an annular inlet passage between thin wall 50 and wall 46 of turbine housing 40. In this passage is a thin wall annular flange 64 slotted to fit over the vanes. The flange is part of a thin wall ring 62 stamped from stainless steel movable across the passage to control the inlet area thereof. The ring 62 is movable by actuators 80 (only one shown) having rods 74 connected to the ring. Springs 116 act on the rods 74 to urge the flange 64 towards the wall 46 thus reducing the area of the inlet passage so exhaust gas rushes through the reduced inlet and speeds the turbine and compressor providing at manifold 32 an increased air pressure. This increased pressure is used to urge diaphragm 100 in the actuators 80 in opposition to the springs and thus move ring 62 to increase the inlet passage area. The thinness of the ring 62 minimizes the chance that exhaust products will make it stick to vanes 60 and enables the ring to move quickly in response to actuators 80.

Motion Analysis of Rolling Piston in Rotary Compressor

Abstract: This paper is concerned with rolling piston type rotary compressor for alr conditioner. rotating · motion of the rolling piston is theoretically analysed using mathematical model which consists of dynamic equation of rolling piston, equation of force equilibrium and equation of bearing characteristic. Also the motion in operating compressor is measured by detecting the change of electrostatic capacity between rolling piston face and electrode mounted on cylinder head surface. After signal analysis, it is proved that rolling piston is sliding positive and negative alternately on the vane tip and it is rotating forward slowly around its center. Theoretical results are in good agreement with experimental results and the validity of the model is verified.

Pressure control means for refrigeration systems of the energy conservation type

Abstract: A refrigerating system of the type used in supermarkets for refrigerating foods merchandised in refrigerated display cases, utilizes a control valve sensitive to pressures in a surge receiver and the liquid line. The valve opens whenever the receiver pressure drops below that of the liquid line more than a predetermined amount, to force hot gas from the compressor discharge line into the receiver. An elevation of the receiver pressure results, until the predetermined pressure differential between the liquid line and the receiver is re-established.

Head pressure maintenance for gas defrost

Abstract: A closed circuit refrigeration system includes a compressor, a remote condenser connected to the output of the compressor, and one or more evaporators coupled within the system. A hot gas defrost system is included to rapidly obtain a high operating defrost gas pressure upon the initiation of a defrost cycle and to thereafter maintain an adequate pressure for hot gas defrosting of the evaporators. The hot gas defrost system includes a differential pressure regulated valve which closes the compressor discharge line to shunt the hot gas discharge directly into a hot gas defrost manifold. The differential valve is controlled by a defrost control means. The refrigeration system can also include a receiver tank and a by-pass conduit for shunting refrigerant liquid through the by-pass conduit rather than through the receiver tank depending upon operating conditions. A method of operating a closed circuit refrigeration system with the above features is set forth.

Turbo charger for a combustion engine

Abstract: The invention relates to a turbocharger making it possible to super charge an internal-combustion engine, especially an internal- combustion engine equipping a vehicle This turbocharger comprises a reversible generating/receiving electromagnetic machine 9 associated with the connecting shaft 1 connecting the compressor 2 and the turbine 3; the windings 9b of the stator of this machine are connected electrically to electrical switching means and to control and regulation means which make it possible to carry out the switchings from one state to another, in order either to supply a charging current to a battery or to participate in the driving and acceleration of the connecting shaft 1 and therefore of the compressor 2

Steam cooled gas generator

Abstract: A reheat gas and double reheat steam turbine combined cycle is provided in which the outer compressor shell and gas generator turbine are modified for steam cooling to control tip clearances of the rotating blades of the compressor and gas generator turbine with the respective shells which confine the blading.

Multi-purpose compressor controller

Abstract: The compressor motor controller of the present invention includes a hot motor detector adapted to be coupled to a plurality of temperature sensors for detecting an overtemperature condition of the compressor motor. The hot motor detector incorporates logic switching means for generating a motor control signal. A self diagnostic sensor is coupled to the hot motor detector for detecting an electrically shorted condition of the temperature sensors while a low voltage detector is coupled to the hot motor detector for sensing a low line voltage condition. Means are provided for protecting the compressor motor against the undesirable effects of short cycle operation while a lubricating oil pressure detector receives signals from a pressure transducer which are representative of oil pressure. A self-contained power supply provides a source of electrical power to the controller while an isolated output means is coupled to the separately mounted motor starting contactor for controllably energizing the compressor motor.

The Performance of Centrifugal Compressor Channel Diffusers

Abstract: Test results pertaining to the characteristics of single-stage centrifugal compressors with backswept impellers and channel-type diffusers are presented and analyzed to formulate major performance criteria influencing maximum diffusion capability. For any given stage, it was determined that stage surge (when triggered by diffuser stall), occurred near a constant mean stream velocity diffusion ratio between the impeller tip and diffuser throat. This diffusion ratio attained a maximum value of 1.8 for impeller tip Mach numbers less than unity, but was not unique for all stages, being more intimately coupled with throat blockage accumulation as a function of diffusion rate. This was identified by testing some vaned diffusers beyond the stall limit where rapid blockage accumulation precipitated an immediate decrease in channel diffuser and system static pressure recovery. The results of various experiments in the vaneless space are also described to illustrate the sensitivity of the vaneless space flow upon centrifugal compressor performance.Copyright © 1982 by ASME

Compressor boundary layer bleeding system

Abstract: Acoustically sized bleed passages are provided in the shroud wall of a rotary compressor to admit expansion waves to the suction-sides of successive passing blades to control the boundary layer. The expansion waves are generated by reflecting compression waves formed in the passages by the pressure sides of passing blades. The passages are oriented to receive high pressure bleed gas at maximum gas particle velocity, and the passages are configured to diffuse the gas to increase static bleed pressure.

Method and apparatus for controlling the operation of an indoor fan associated with an air conditioning unit

Abstract: A method of operating an air conditioning system including a refrigeration circuit having a compressor and a thermostat for sensing heating and cooling needs together with an indoor fan is disclosed. The indoor fan operation is controlled based upon a microprocessor control remembering whether or not the unit was in continuous fan operation prior to the compressor operating to satisfy a heating or cooling need. Through the setting of a flag the microprocessor remembers the previous inputs such that operation of the fan may be controlled regardless of the condition of the compressor especially as concerns operation of the fan when the compressor is prevented from operating due to a safety, overload or timed off condition.