Abstract: A dual-pack, aircraft environmental control system has each pack dedicated to providing a temperature-controlled air supply to a corresponding compartment, either the crew or passenger, of the aircraft. Each refrigeration pack is fed hot, compressed bleed air from an associated turbine engine on the aircraft. During normal operation, the pack associated with a particular compartment on the aircraft provides the air supply with independent temperature control to that compartment. However, during failure of one of the refrigeration packs and the resulting operation of the other pack, the environmental control system is able to provide independent temperature control of the air supplied to each compartment.

Abstract: An air cycle environmental control system for an aircraft cabin is disclosed which utilizes cabin exhaust air to power a first stage turbine. This provides a significant increase in compressor power which increases the turbine cooling available in a second stage turbine. The ram air consumption is also reduced due to the cabin exhaust air being ported to the ram air inlet where it merges with the ram air prior to cooling of the bleed air supply in a dual heat exchanger.

Abstract: Gas compression and chilling systems, particularly adapted for compressing and chilling gas for transmission through arctic pipelines are provided with a cross heat exchanger for transferring heat from gas compressed to the inlet gas to the compressor. The heat exchanger is disposed upstream of an expander which may comprise a mechanical expander or a throttling valve, or both, to achieve a predetermined final output pressure and temperature. An aerial heat exchanger is interposed between the compression and expansion stages upstream of the inlet gas heat exchanger. One embodiment of the system uses two stages of compression, aerial cooling and expansion to the final temperature and pressure.

Abstract: A method for supplying cooling air on vehicles such as high speed aircraft includes diverting high pressure air from the compressor section of a gas turbine engine, cooling this air in a heat exchanger, and expanding the diverted high pressure air through an auxiliary turbine. Coolant in the heat exchanger may be inlet ram air, fan air, or aircraft fuel (which may be endothermic), and the coolant is ultimately introduced into the engine downstream of the compressor section. An auxiliary compressor may be used to further compress the diverted high pressure air or coolant prior to the flowing thereof through the heat exchanger, and one or more auxiliary turbines may be used to power the auxiliary compressor, or mechanical accessories on the vehicle.

Abstract: This invention is a gas wave refrigeration method and a corresponding device used in an energy recovery system, which employs a mechanism creating a pulsating flow wave resonant interactions to generate cooling and heating effects without any mobile parts used in the device. The said system includes a precooler, a gas-liquid separator, and a gaseous wave refrigeration device (GWRD). The GWRD consists of a flow buffering chamber, a convergent nozzle, a oscillating chamber, resonant tubes, and a flow stabilizer. The operation of the GWRD is based on a pulsating flow production created by wave interactions between laterally oscillating high speed jets and resonant tubes. Such method of the pulsating flow production omits a conventional bistable element or other flow switching elements used in prior similar devices. A longitudinal resonating phenomenon of resonant tubes which provides a energy transformation and cooling effect is produced simultaneously by such wave interaction process.

Abstract: A gas turbine engine cooling system. Hotter engine compressor air is cooled by a heat exchanger using a colder engine fluid (such as fuel or lower pressure (colder) engine compressor air. The cooled air passes through the compressor section of an auxiliary turbocompressor and is used to cool the engine high pressure turbine. Some of the cooled air (or uncooled discharge air from the engine high pressure compressor) is used to drive the turbine section of the turbocompressor. The spent air exiting the turbine section of the turbocompressor is used to help cool the engine low pressure turbine.

Abstract: A method and apparatus is disclosed to provide a fuel efficient source of readily converted energy to an isolated or remote energy consumption facility. External heat from any of a large variety of sources is converted to an electrical, mechanical, heat or cooling form of energy. A polyatomic working fluid energized by external heat sources is dissociated to a higher gaseous energy state for expansion through a turbine prime mover. The working fluid discharge from the turbine prime mover is routed to a recouperative heat exchanger for exothermic recombination reaction heat transfer to working fluid discharged from the compressor segment of the thermodynaic cycle discharge. The heated compressor discharge fluid is thereafter further heated by the external heat source to the initial higher energy state.

Abstract: A method and an arrangement for compressing gas in a compressor station for a gas pipeline, especially in areas of permanent frost, wherein the gas is supplied in the gas pipeline to the compressor station at an entry pressure and the gas is returned to the pipeline for further transportation in the pipeline at a desired exit temperature and at an exit pressure which is higher than the entry pressure. The gas is initially compressed at least during individual time intervals to an excess pressure which is substantially higher than the desired exit pressure. The compressed gas is then cooled by heat exchange to a temperature above the desired exit temperature. Finally, the gas is further cooled to the desired exit temperature by expanding the gas from the excess pressure to the exit pressure.

Abstract: An air conditioning system (10), being powered by a supply of compressed air, includes an air cycle machine (12) and incorporates a pair of regenerable bed filters (44,46). In operation, the filters are alternately cycled in and out of service with one of the filters receiving pressurized air for filtration from the air cycle machine compressor (30), while a backflow of purge air is passed through the other filter to remove accumulated contaminants from the bed thereof, thereby regenerating the filter. The purge air comprises conditioned air from the air cycle machine turbine (32). The contaminant laden purge air discharging from the filter being cleansed, is passed to a subatmospheric pressure region (77) in the ram air duct (20) upstream of the air cycle machine fan (28) and downstream of the heat exchangers (22, 24) for venting therefrom to the atmosphere via the fan (28).

Abstract: In a low temperature generation process, compressed gas (3) at high pressure enters from an inlet nozzle (1) and alternately expands into one of two resonator tubes (A,B) of an expansion engine. The expanding gas excites standing acoustic waves (4) in the resonator tubes (A,B). The acoustic energy of the waves (4) is converted into electrical energy by acoustic/electric power converters and is led away outside the "cold area" of the tubes. The expansion engine contains one or more resonator tubes with a common inlet nozzle (1). Each resonator tube has an acoustic/electric power converter (5) and an exhaust port (6). Together with a compressor, a heat exchanger and a heat sink, the expansion engine provides a very effective cooling system which may be used for the cooling of small electronic devices like chips or modules.

Abstract: Air is conditioned by compressing air at a first location during a first interval of time and storing the compressed air at the first location. Compressed air stored at the first location is transported by pipeline to a second location remote from the first location during a second interval of time different from the first interval of time and expanded at the second location. The expanded air is delivered to enclosures at the second location. The first interval of time is preferably during the night when the power required to compress the air is relatively inexpensive.

Abstract: An air cycle machine (10) has a first stage turbine (60) mounted to a central portion of a common shaft (12), a compressor (50) mounted to the central portion of the shaft (12), a second stage turbine (30) mounted to a first end of the shaft (12), and a fan (40) mounted to a second end of the shaft (12), all for rotation therewith about a longitudinal axis (14). The first and second stage turbines (60, 30) are operative to extract energy from a flow of compressed air for driving the shaft (12), and the fan (40) and the compressor (50), in rotation about the axis (14).

Abstract: In a normal mode, a primary heat exchanger for heated bleed airflow is situated upstream of an aircraft air conditioner compressor. A secondary heat exchanger is located downstream of the compressor. In response to hot and humid environmental conditions, three-way switching valves reposition the primary heat exchanger downstream of the compressor. The result will be the reduction of heat exchange exit temperature, which translates into lower turbine inlet and outlet temperatures at satisfactory airflow rates.

Abstract: A gas turbine engine cooling system. A first turbocompressor and a heat exchanger are fluidly interconnected and are each in fluid communication to receive air of differing pressures and temperatures. Typically, such air is received from various regions of the engine low pressure compressor and the engine high pressure compressor. The system delivers air through a duct to a portion of the engine for cooling, such as the engine high pressure turbine region, at lower temperatures and higher pressures than if cooling air were directly ducted from the engine compressor to the engine turbine.

Abstract: A cryogenic rectification system employing a coupled expander and compressor wherein a process stream employs system energy to drive the expander to compress product nitrogen while generating refrigeration to assist in carrying out the rectification thereby carrying out the rectification at a lower pressure.

Abstract: A system for conditioning working fluid in environmental control systems includes arrangements for minimizing icing from a variable flow velocity turbine exit flow at subfreezing conditions, wherein the turbine is very closely located to the downstream heat exchanger, including a backpressure plate for minimizing flow velocity stratification, an internal bypass passage arranged to produce a relatively predictable bypass flow ratio regardless of the flow velocity stratification, and other anti-icing techniques.

Abstract: A process and installation for producing cooled air and water or energy and water from hot damp air. In the former embodiment, the hot damp air is first compressed. Then, the compressed air is at least partially dehumidified and cooled. The dehumidified, cooled, compressed air is thereafter expanded. In the latter embodiment, the hot damp air is first expanded. The expanded air is thereafter compressed. In addition to the above, the invention also has utility in desalinating salt water.

Abstract: The incoming compressed air is partly expanded in a high pressure turbine, after which a portion of the expanded air is again expanded in a low pressure turbine. The inlet temperature of the latter is clearly higher than that of the high pressure turbine. Application to the production of liquid nitrogen and liquid oxygen.

Abstract: Energy recovery systems for cold storage warehouses refrigerated by mechanical refrigeration apparatus coacting with a energy recovery unit including a turbine driving an electromotive generator. The cogenerator turbine is driven by the kinetic energy extracted from refrigerant flowing through a first conduit system connecting the compressor, evaporators and condenser of the refrigeration or by the kinetic energy extracted from a coolant being pumped through a second conduit system independent of the first conduit system to cool the compressor as it becomes heated during compression of refrigerant from a vapor phase to a liquid phase during the refrigeration cycle. The extraction of the kinetic energy of the refrigerant flow or coolant flow and the heat generated by the compressor during the refrigerant compression phase represents useful work obtained from the energy recovery system from available surplus energy that otherwise would be wasted.

Abstract: A fan inlet and diffuser apparatus (30) is provided with a lobed mixer (60) for intermixing fan bypass air (25) with a flow of fan discharge air (27). The fan inlet and diffuser apparatus (30) is particularly adapted for use in a inducing a flow of cooling air (21) through an upstream heat exchanger (20) and thence directing a portion (23) of the cooling air passing from the heat exchanger to the inlet side of the fan (14) of an air cycle machine (10), while directing the remaining portion (25) to bypass the fan (14) and pass into the central outlet flow passage (52) flowing over the mixing ejector (60) which imparts a directional swirl to the bypass flow (25) and a counter swirl to the fan discharge flow (27) passing from the fan outlet through the interior of the mixer (60), thereby enhancing the mixing of these two flows within the passage (52).

Abstract: An auxiliary refrigerated air system includes first and second tandemly-arranged auxiliary turbine components, air dividing and mixing valves, an air bypass loop, an auxiliary air compressor, and a heat exchanger. The air dividing valve is connectable to a suitable input air source for receiving and dividing input air into first and second portions. The air mixing valve is connected in communication between an exit side of the first auxiliary turbine component and an entrance side of the second auxiliary turbine component for mixing the first portion of the input air with energy-depleted air exiting from the first auxiliary turbine component. The air bypass loop is connected in communication between the dividing and mixing valves for bypassing to the mixing valve the first portion of the input air diverted from the dividing valve.

Abstract: An auxiliary refrigerated air system includes first and second tandemly-arranged auxiliary turbine components, air mixing and dividing valves, an air recirculation loop, an auxiliary air compressor, and a heat exchanger. The air mixing valve is connectable to a suitable input air source for receiving and mixing input air with dilution air and producing an air mixture. The air dividing valve is connected in communication between an exit side of the first auxiliary turbine component and an entrance side of the second auxiliary turbine component for diverting a portion of the energy-depleted air exiting from the first auxiliary turbine component. The air recirculation loop is connected in communication between the mixing and dividing valves for recirculating to the mixing valve the portion of the air diverted by the dividing valve to provide the dilution air to the mixing valve.

Abstract: An Ericsson cycle machine is disclosed which can be used for refrigeration, liquefaction of nitrogen or as an engine. The invention includes a liquid ring compressor linked to a liquid ring expander by a gas loop that includes a recuperator. As a refrigeration unit, the liquid ring in the compressor is channeled through a heat exchanger to reject waste heat and liquid is tapped from the expander liquid ring and used as a refrigerant.

Abstract: An advanced Environmental Control System (ECS) for use in conjunction with a turbine engine to provide conditioned, pressurized air to an enclosed space such as an aircraft cabin, as well as cooling capacity for the aircraft avionics. The ECS features a dual turbine air cycle machine to minimize the amount of bleed air or power required from the turbine engine.

Abstract: An advanced hybrid air and vapor cycle environmental control system (ECS) to provide conditioned, pressurized air to an aircraft as well as liquid cooling for the avionics of the aircraft.

Abstract: A hybrid vapor cycle-air cycle environmental control system (ECS) for efficiently providing a flow of conditioned, pressurized air to an enclosed space such as an aircraft cabin.

Abstract: A ram air cooling system for cooling electronic components in an aircraft ovides automatic switching from a high ram air speed cooling mode (ACM) to a low ram air speed cooling mode (RAM). The cooling system receives variable speed ram air during the flight of the aircraft and includes an automatically controlled valve for either directing high speed ram air to a precooling means prior to cooling the electronic components or directing low speed ram air directly to the electronic components without precooling. The automatically controlled valve is controlled by programmable logic module means for comparing the cooling efficiency of the electronic components by precooled ram air with the cooling efficiency of the electronic components by the non-precooled ram air. The cooling efficiencies are calculated from temperature measurements of the ram air at several locations in the system of the invention.

Abstract: The cooling circuit for cooling a computer in a room employs a work-performing expansion. The heat generated by the expansion is supplied to the back flowing coolant in the coolant circuit via a second closed coolant circuit. The second circuit may employ a cooler outside the room to withdraw the heat added to the second circuit.

Abstract: The present invention utilizes a turboexpander coupled with a compressor in place of the Joules-Thomson expansion valve in a conventional refrigeration to achieve higher efficiency. More specifically the refrigeration is used in removing condensable hydrocarbons or chemical vapors from air which has been contaminated during loading and unloading at bulk plants. The more efficient turboexpansion cycle allows the use of saturated lower aliphatic hydrocarbons, such as ethane as refrigerant, the use of which would be precluded from normal Joules-Thomson expansion cycles. The turboexpander work is used to drive a compressor which partially recompresses the expanded refrigerant gas, providing an essentially isentropic expansion. Because the turboexpander and the compressor operate on the same fluid, the mass flows through both are equal thereby alleviating control and loading problems.

Abstract: The plant for the periodic charging and discharging of a gas reservoir comprises a gas circuit containing a compressor and a heat exchanger. A line for supplying the gas for storage and for discharging stored gas to a consumer is connected to the gas circuit. The gas is stored as a gas at low temperature and elevated pressure or as a liquid gas at substantially ambient pressure. A heat exchanger disposed in the gas circuit is operated as a cooler or heater depending on whether gas is to be stored or discharged. The heat-transfer or refrigerant liquid flowing through the heat exchanger is either cooled in a refrigerating machine or heated in a heater. Depending upon requirements, a gas, e.g. natural gas, can be prepared in one and the same plant for charging a reservoir or for emptying the same.

Abstract: A cooling plant load reduction mechanism utilizing "waste" heat for powering a rankine cycle device for the simultaneous additional cooling of a structure and production of electricity that substantially eliminates the need to purchase external power to run the device. Overall cost of producing cool air in a typical cooling process is thereby substantially reduced.

Abstract: A cryocooler system including a reversed Brayton cycle turbo-refrigerator system having a surge control valve in the bypass line between the compression section inlet and outlet. The compression section includes at least one compressor and an aftercooler which rejects the heat of compression to a heat sink. The cooling section includes at least one regenerator and a turbo-alternator for expansive cooling of the working fluid.

Abstract: The method consists of recovering heat contained in the combustion gases in a first heat exchanger or boiler, recovering the heat given off by the engine or turbine in the form of steam and/or hot water, leading the previously cooled, in a second heat exchanger, combustion gases to a pressure gas holder, impelling the gases to a washing and cooling column and passing them through CO.sub.2 absorption columns wherein this latter is picked up whereas the remainder of gases, specially N.sub.2, are left free, and conventionally performing the steps for obtaining both gases. For performing all of the obtention procedure, use is made of only the combustion generated energy, thus thoroughly recovering the above gases with a whole benefit of the energy contributed by the hydrocarbons.

Abstract: A fluid pressure, free piston engine, such as a centrifugal piston expander, provides a cyclically varying torque to a rotatable output shaft. A unidirectional or overrunning rotational clutch comprising two relatively rotatable elements has one element secured to a unidirectionally rotatable load and the other element driven by the output shaft of the centrifugal piston expander. The engine output shaft further drives, through appropriate gearing, a battery operated, starting motor-generator unit. The motor-generator is employed to initially rotate the expander to sufficient speed to ensure the centrifugal return of the free pistons of the centrifugal piston expander to their radially outermost positions. After start-up of the centrifugal piston expander, the starting motor functions as a generator to recharge the battery during the high torque portions of rotation of the engine output shaft, and during the low torque portions of the power output shaft, again functions as a motor to increase such speed.

Abstract: A liquified hydrocarbon is vaporized in the installation by being brought into direct contact with heated compressed hydrocarbon in a heat exchanger. The hydrocarbon is compressed in a compressor (2), which is driven by a steam turbine (1). To heat the compressed hydrocarbon, the hydrocarbon is brought into heat exchange with the waste steam from the steam turbine, in the process of which the waste steam condenses. The product can be withdrawn before or after the compressor (2).

Abstract: Cogeneration of electricity and saleable refrigeration is achieved by passing pipeline gas with added methanol through a turbo-expander coupled to an electrical generator so that moisture in the gas forms an aqueous methanol condensate separable from the cold, expanded gas. The condensate is distilled to separate discard water from recycle methanol. After recovering refrigeration therefrom, the expanded gas is warmed to a temperature above 32.degree. F. by adding all the required heat as reboiler heat for the distillation and passing the expanded gas in heat exchange with distilled methanol vapor which is liquefied and used partly as reflux and partly as recycle methanol.

Abstract: A gas separating method and a gas separating apparatus according to the present invention effectively carry out the generation of the cryogenic effect within a plant for separating and extracting valuable gases such as nitrogen, oxygen, argon or the like from raw gas. For this purpose, the arrangement is such that low temperature gas within a process is subjected to a thermal exchange with the raw gas in a heat exchanger and is thermally restored; the thus restored gas is fed to a booster driven by an expansion turbine to be pressurized therein; the thus pressurized gas is cooled to the normal temperature by a cooler; the cooled gas is further cooled in the heat exchanger; and the still lower temperature gas is supplied to the expansion turbine to be adiabatically expanded, thereby generating the cryogenic effect.

Abstract: A process of and a device for power- and air-conditioning fresh air generation in an aircraft, which are equipped with main power plants and an auxiliary power unit driving an air-conditioning compressor, both of which are supplied with air-conditioning exhaust air from the passenger- and/or pilot cabin and/or with exhaust air from the boundary layer suction for the purpose of economical operation.

Abstract: An apparatus for providing relatively dry, oil free compressed instrument air includes a first compressor for receiving air at ambient temperature and pressure and compressing it to an elevated pressure. A cooler is provided for cooling the compressed air while a vortex directs its cold fraction discharge air to a second compressor. A heat exchanger is disposed intermediate the cooler and the vortex tube for transferring heat from the cooled, compressed air to the cold fraction discharge air. An air-water separator may be disposed between the vortex tube inlet and the heat exchanger for removing any condensed water from the compressed air. The second compressor receives the cold fraction discharge air and generates a supply of instrument air at a pressure not in excess of 25 p.s.i.g. and which has a dewpoint below the freezing temperature of water. A method for producing relatively dry, compressed instrument air is also disclosed.

Abstract: Apparatus and method for conditioning a flow of working fluid includes a parallel, bypass anti-icing flow of warm fluid which is induced and automatically controlled in relation to critical system operating parameters while minimizing parasitic power losses to improve overall system efficiency.

Abstract: An air cycle air conditioning system (10) for rgulating the temperature and pressure of diverse loads includes open and closed loop sections (12) and (16). A first load (14) requiring heating or cooling with constantly supplied fresh air is provided with chilled air from first turbine (75) and warm air from first bypass valve (50). A second load (20) which can be heated or cooled with a supply of recirculating air is provided with chilled air from second turbine (130) and warm air from a second bypass valve (170). Air is supplied to the second turbine from a compressor driven by the first turbine whereby the first turbine maintains the temperature of both loads either by the direct supply of air thereto or by driving another turbo-compressor system.

Abstract: The present invention relates to the recovery of heat and/or condensable liquid from a gaseous environment utilizing an open cycle heat pump system. The open cycle heat pump system is employed to alter the temperature of a gas by compression, expansion, heat exchange, and combinations thereof, to condense selected vapors carried in the gaseous environment for removal from the gas. The open cycle heat pump system can also be used to extract the heat from a gas for use as desired.

Abstract: The high pressure of pipeline gas is reduced to the low pressure of a distribution system with simultaneous generation of refrigeration by passing the gas through two successive centrifugal compressors driven by two turbo-expanders in which the compressed gas is expanded to successively lower pressures. Refrigeration is recovered from the gas as it leaves each turbo-expander. Methanol is injected into the pipeline gas before it is expanded to prevent ice formation. Aqueous methanol condensate separated from the expanded gas is distilled for the recovery and reuse of methanol.

Abstract: The disclosure provides an oscillatable body mounting a cylinder defining an elongated fluid pressure chamber having at least one end thereof remotely located with respect to the axis of oscillation. The elongated fluid pressure chamber accommodates a free piston which reciprocates along the length of the chamber according to fluid pressure applied thereto. Solenoid operated inlet and exhaust valves are provided at each end of the elongated fluid pressure chamber, and sensing devices, responsive to the passage of the free piston therethrough are disposed on opposite ends of the elongated fluid pressure chamber and adjacent the medial portions thereof to control the operation of the inlet and exhaust valves in accordance with the desired objective to either maximize the extraction of mechanical energy from a pressured gas in the form of oscillating movements of the body, or maximize the expansion of the pressured gas to derive the greatest possible cooling effect therefrom.

Abstract: The fuel required to provide the energy for compressing a gas can be reduced by compressing the gas substantially adiabatically through a pressure ratio of at least 2.5:1 in a compressor, cooling the hot compressed gas by heat exchange with water at superatmospheric pressure, further heating the water to produce super-heated steam and using the superheated steam to drive the compressor. The total amount of fuel consumed can be considerably less than that used for compressing gas conventionally (i.e. substantially isothermally).

Abstract: An air conditioning system of the air cycle heat pump type for selectively heating and cooling a residence or similar space environment. In one embodiment, a combustor and associated Brayton cycle turbine provide the primary drive to a compressor constituting the heat pump. In a second embodiment, the Brayton turbine is replaced by an electric motor coupled to drive the compressor shaft. An auxiliary turbine is also coupled to the drive shaft to provide auxiliary drive derived from the operation of a portion of the system at sub-atmospheric pressure. In this portion, during the cooling mode, water is evaporated into the system to further assist in cooling by removing the latent heat of vaporization.

Abstract: An air conditioning system of the air cycle heat pump type for selectively heating and cooling a residence or similar space environment. In one embodiment, a combustor and associated Brayton cycle turbine provide the primary drive to a compressor constituting the heat pump. In a second embodiment, the Brayton turbine is replaced by an electric motor coupled to drive the compressor shaft. An auxiliary turbine is also coupled to the drive shaft to provide auxiliary drive derived from the operation of a portion of the system at sub-atmospheric pressure. In this portion, during the cooling mode, water is evaporated into the system to further assist in cooling by removing the latent heat of vaporization.

Abstract: The herein disclosed method of cold generation provides for the compression of refrigerant and its subsequent cooling. Then, at least part of the refrigerant flow is expanded, accompanied by the generation of acoustic or another type of wave energy which is extracted from the expansion zone by way of converting it to energy of another kind. Provision is made of a plant for accomplishing the method, wherein a refrigerant expansion device 20 includes a gas-jet mechanowave converter 21 and a wave energy converter 22 in the wave relationship therewith.

Abstract: The invention provides a method and apparatus for operating any centrifugal piston expander to convert energy derived from a heat source into mechanical energy. Pressured gas received from the heat source is circulated through the centrifugal piston expander, then to a series connected heat exchanger and compressor to recompress same and to remove sufficient heat to satisfy the entropy requirements of the closed cycle, and then is resupplied to the heat source for recirculation. Several types of centrifugal piston expanders are disclosed including one type wherein the centrifugally produced stroke of each piston is utilized to force the expanded gas into the subsequent apparatus.

Abstract: The invention relates to a plant for utilization of low-potential waste heat of a gas-pipeline compressor station in a heat consumer which is outside the station such as e.g. district heating systems for homes, for industrial or agricultural purposes. The compressor stations of this type have a compressor driven by a gas motor or gas turbine.The improvement is in that a surface heat exchanger (7) cooled with liquid, preferably with water is provided for cooling the gas after leaving the compressor and being warmed in the course of compression. The heat exchanger is connected to the heat consumer through a liquid conduit having a circulation pump in it (FIG. 1).