517results about "Compression machines with cascade operation" patented technology

The invention discloses an oil return control method and system of a cascade heat pump system, and the control method comprises the following steps: 1, detecting a first state parameter of an intermediate heat exchanger so as to adjust a compressor and a throttling device at a low-temperature side and a high-temperature side, and when a second state parameter at the low-temperature side meets a condition, adjusting the compressor and the throttling device at the high-temperature side; the operation frequency of the compressor on the low-temperature side / high-temperature side is adjusted again, and return oil flushing is conducted on the intermediate heat exchanger; the second method comprises the following steps: respectively calculating the accumulated carbonization time of the corresponding lubricating oil in the low-temperature side or the high-temperature side, and judging whether the lubricating oil is replaced or not based on the accumulated carbonization time; and the third method comprises the steps that the accumulated low-frequency operation duration of the compressor on the low-temperature side or the high-temperature side in the low-frequency state is detected, and when the triggering condition is met, the operation frequency of the compressor is increased. Based on the control method, the operation reliability and the energy efficiency performance of the cascade heat pump system are improved, and the service life of equipment is prolonged.

The invention relates to the technical field of sample storage, particularly provides a cascade refrigeration system and a control method of an ultralow-temperature sample library, and aims to solve the problem that normal operation of a unit is affected due to abnormal oil return of an existing cascade refrigeration system. In order to achieve the purpose, the cascade refrigeration system comprises a high-temperature-stage refrigeration unit, a low-temperature-stage refrigeration unit and an intermediate heat exchanger, the low-temperature-stage refrigeration unit comprises a low-temperature compressor, an oil separation device and a heat exchange device, the oil separation device comprises a plurality of oil separators arranged in sequence, and a heat exchanger is arranged between every two adjacent oil separators; the low-temperature compressor, the oil separation device, the intermediate heat exchanger and the heat exchange device are communicated with one another to form a low-temperature-stage refrigerant circulation loop, and the high-temperature-stage refrigeration unit and the intermediate heat exchanger are communicated with one another to form a high-temperature-stage refrigerant circulation loop. The oil separation efficiency can be improved, deep oil removal is achieved, and oil return is remarkably improved.

An assembly includes a fluid conditioning system including a cascade module and an active charge compensator integrated into the fluid conditioning system. The fluid conditioning system is transformable between a first mode and a second mode. In the first mode, the fluid conditioning system includes a first vapor compression loop and a second vapor compression loop. The first vapor compression loop and the second vapor compression loop are thermally coupled at the cascade module and the second vapor compression loop is fluidly separate from the first vapor compression loop. In the second mode, the fluid conditioning system includes a single vapor compression loop. The active charge compensator is operable to control a working fluid charge within the fluid conditioning system based on the mode of operation selected from the plurality of modes.

The invention discloses an assembly type pressure-bearing refrigeration system, and particularly relates to the technical field of refrigeration equipment, the assembly type pressure-bearing refrigeration system comprises a container and a combined type refrigeration cycle unit integrated in the container, and the combined type refrigeration cycle unit comprises a low-temperature-stage refrigeration cycle assembly and a high-temperature-stage refrigeration cycle assembly; the low-temperature-stage refrigeration cycle assembly comprises a pressure-bearing liquid storage tank, and the bottom of the pressure-bearing liquid storage tank is fixedly communicated with a refrigerant liquid outlet. Through high-temperature-stage and low-temperature-stage double-circulation collaborative design and a safe pressure control mechanism, the technical bottleneck of a traditional refrigerating system is broken through, the contradiction that low temperature and safety of traditional high-pressure refrigerating equipment cannot be considered at the same time is solved, stable and safe operation at the ultralow temperature ranging from-20 DEG C to-30 DEG C is achieved, and the refrigerating efficiency is improved. Ultralow-temperature refrigeration is achieved through pressure bearing and high-temperature-level and low-temperature-level double-circulation cooling, so that larger-area refrigeration is achieved through lower temperature, modularized integration of the whole system is achieved through a container, and the adaptive pain point that a traditional refrigeration system is fixedly installed and cannot be moved is solved.

A primary refrigerant circuit allows circulation of a primary refrigerant and includes a primary compressor, a cascade heat exchanger, and a primary heat exchanger. A secondary refrigerant circuit allows circulation of a secondary refrigerant and includes a secondary compressor, the cascade heat exchanger, and a utilization heat exchanger. The primary refrigerant circuit includes a first connecting pipe, a primary first connection pipe, and a liquid connecting pipe connecting the cascade heat exchanger and the primary heat exchanger, a primary suction flow path of the primary compressor, a primary subcooling circuit connecting the liquid connecting pipe and the primary suction flow path, and a primary subcooling expansion valve provided in the primary subcooling circuit.

This invention provides a carbon dioxide recovery cascade refrigeration system, including a circulation loop and a first heat exchanger, a compressor, a condenser, and a first oil drain pipe disposed on the circulation loop. The circulation loop is used for the flow of carbon dioxide heat exchange medium. The first heat exchanger has independent first and second heat exchange channels. The first heat exchange channel has a first inlet and a first outlet. The second heat exchange channel has a second inlet and a second outlet respectively connected to the circulation loop. The carbon dioxide heat exchange medium in the second heat exchange channel is used to reduce the temperature of the medium in the first heat exchange channel. An oil drain port is provided at the bottom of the first heat exchange channel. The gas inlet of the compressor is connected to the second outlet of the first heat exchanger. The condenser is located downstream of the compressor and is used to condense the carbon dioxide heat exchange medium after compression by the compressor. The oil drain port is connected to the inlet of the compressor through the first oil drain pipe. This system uses carbon dioxide as the heat exchange medium, resulting in low cost.

The control method comprises the steps that the rotating speed of a high-temperature-stage inverter compressor is mainly comprehensively determined by the high-temperature-stage exhaust temperature, the high-temperature-stage condenser temperature, the high-temperature-side outlet temperature of an intermediate heat exchanger and the high-temperature-stage return air temperature; through dynamic adjustment of the first fuzzy PID controller, the working condition and energy efficiency of the high-pressure side of the system are optimized; the rotating speed of the low-temperature-stage frequency conversion compressor is mainly comprehensively determined by the temperature in the box, the real-time rotating speed of the high-temperature-stage compressor, the low-temperature-stage exhaust temperature, the temperature of the intermediate heat exchanger and the low-temperature-stage return air temperature, and the rotating speed is dynamically adjusted through the second fuzzy PID controller so as to ensure that the temperature in the box is accurate and stable and is matched with the high-temperature-stage capacity in real time. Through cooperative control of the parameter groups, the problems of low efficiency and unstable operation caused by mismatching of two-stage capabilities of the cascade system are solved, and efficient, stable and reliable operation of the system under all working conditions is realized.

The invention provides a refrigerating system and an air conditioner, the refrigerating system comprises a first compressor, a first heat exchanger, a first valve, a second heat exchanger and an ejector, the first compressor, the first heat exchanger, the first valve and the second heat exchanger are connected to form at least partial structure of a first refrigerating loop; the ejector comprises a first inlet end, a second inlet end and a first outlet end, the first inlet end is communicated to the outlet end of the second heat exchanger, the second inlet end is communicated to the exhaust end of the first compressor, and the first outlet end of the ejector is communicated to the inlet end of the second heat exchanger. According to the invention, the evaporation or condensation heat exchange efficiency can be improved, so that a refrigerant which does not fully exchange heat can continuously participate in heat exchange circulation, and the compressor is prevented from sucking air and carrying liquid; the problem that in a heat exchanger of a refrigerating system in the prior art, heat exchange of refrigerants is not sufficient, and consequently the refrigerants are not completely evaporated or condensed is effectively solved.

The utility model discloses a low-temperature refrigerating system in a high-humidity environment. The low-temperature refrigerating system comprises a dehumidifier arranged below a refrigerating evaporator, the dehumidifier is communicated with the cascade refrigerating unit through a refrigerant pipeline, a refrigerant inlet pipeline is provided with an electromagnetic valve used for controlling refrigerant to enter, and a refrigerating discharge pipeline is provided with a temperature sensor used for monitoring the temperature of an outlet of the dehumidifier. The box body temperature sensor is arranged in the environment test box and is used for acquiring the temperature in the box body. According to the scheme, the problem that the surface of the evaporator frosts during cooling under the high-humidity working condition can be solved.

The installation (21) comprises: a primary refrigerant circuit (22), including: - an outdoor unit (23) comprising at least: a first compressor (34), a first heat exchanger (25) configured to exchange heat between a first refrigerant and the outside air, and at least one first expansion valve (26), - an indoor unit (29) comprising at least one second heat exchanger (30) configured to exchange heat between the first refrigerant and the inside air, a secondary refrigerant circuit (32) independent of the primary circuit (22), intended to be installed inside the dwelling and comprising: - a water heater comprising a tank (33), a condenser (35), a second compressor (34) and at least one second expansion valve (36),the primary circuit (22) comprising at least one third heat exchanger (37) allowing the primary circuit (22) and the secondary circuit (32) to be thermally coupled directly or indirectly. Figure from the abstract: Figure 2,

Systems and methods for regenerative ejector-based cooling cycles that utilize an ejector as the motivating force in a cooling loop to regeneratively sub-cool a refrigerant in a single-stage cooling cycle.

A vapour compression refrigeration system has a main refrigerant circuit having a main gas cooler or condenser arranged in a high pressure branch, a first main evaporator arranged in a first low pressure branch, a main compressor fluidically connecting the first low pressure branch to the high pressure branch, and an expansion device connecting the high pressure branch to an intermediate pressure branch. The system has a by-pass branch connecting the high-pressure branch to the intermediate pressure branch and provided with a by-pass valve, a secondary refrigerant circuit having a secondary gas cooler or condenser arranged in a secondary high pressure branch, a secondary evaporator arranged in a secondary low pressure branch, and a secondary expansion device connecting the secondary high pressure branch to the secondary low pressure branch. A rotary pressure exchanger is fluidically connected to the by-pass branch downstream of the by-pass valve and the secondary refrigerant circuit.

A refrigeration cycle apparatus according to the present disclosure includes a heat medium circuit in which a heat medium circulates. The heat medium circuit includes a plurality of load-side heat exchangers that cause heat exchange to be performed between first refrigerant and the heat medium, a plurality of use-side heat exchangers into which the heat medium supplied from at least one of the load-side heat exchangers flows, and a pump. In the heat medium circuit, the heat medium is supplied to a first load-side heat exchanger and a second load-side heat exchanger by the one pump, where the first load-side heat exchanger is one of the load-side heat exchangers, and the second load-side heat exchanger is one of those of the load-side heat exchangers that supply the heat medium having a temperature different from a temperature of the heat medium that is supplied by the first load-side heat exchanger.

The invention relates to the technical field of ultralow-temperature treatment equipment, in particular to a cascade refrigeration system for a cold therapy instrument, which comprises a first-stage compression cycle module, a second-stage compression cycle module, a third-stage compression cycle module, a fourth-stage compression cycle module, a fifth-stage compression cycle module and a sixth-stage compression cycle module, the first-stage compression circulation module is connected with the second-stage compression circulation module in parallel through the first heat exchanger, and a second heat exchanger and a composite evaporator are arranged on the second-stage compression circulation module; and the third-stage compression circulation module is connected with the second-stage compression circulation module in parallel through the second heat exchanger, and the third-stage compression circulation module is communicated with the composite evaporator. The air conditioner has the effect of increasing the refrigerating temperature range.

The utility model discloses a cascade refrigerating system which comprises a high-temperature-stage refrigerating unit and a low-temperature-stage refrigerating unit. The high-temperature-stage refrigerating unit comprises a high-temperature-stage compressor, a high-temperature-stage condenser and a cascade heat exchanger serving as a high-temperature-stage evaporator. The low-temperature-stage refrigerating unit comprises a low-temperature-stage compressor, a low-temperature-stage evaporator and the cascade heat exchanger serving as a low-temperature-stage condenser in the low-temperature-stage refrigerating unit. A pre-cooling heat exchanger is arranged on a pipeline between the low-temperature-stage compressor and the cascade heat exchanger and arranged on one side of the high-temperature-stage condenser, and the pre-cooling heat exchanger and the high-temperature-stage condenser share a condensation fan. High-temperature and high-pressure gas exhausted by the low-temperature-stage compressor is primarily cooled through the pre-cooling assembly and then is further cooled through the cascade heat exchanger, and the refrigerating capacity of the high-temperature-stage compressor is effectively reduced.

In a cooling system for cooling the interior of a vehicle by circulating a CO2-containing refrigerant, the refrigerant reliably and efficiently cools a battery. A cooling system (100) is provided with: a compressor (1) that compresses a refrigerant; a heat exchanger (2) for cooling the refrigerant from the compressor (1); heat exchangers (5a, 6a) that use the refrigerant cooled by the heat exchanger (2); a refrigerant passage (17) for supplying the refrigerant from the heat exchangers (5a, 6a) to the battery (6); a refrigerant passage (14) for supplying the refrigerant cooled by the heat exchanger (2) to the refrigerant passage (17) without passing through the heat exchangers (5a, 6a); an expansion valve (E2) provided in the refrigerant passage (17); the flow regulating valve (V3) is arranged on the refrigerant channel (14); wherein the control device (80) increases the opening degree of the flow regulating valve (V3) when the specific enthalpy of the refrigerant supplied to the battery (6) exceeds a prescribed range, and decreases the opening degree of the flow regulating valve (V3) when the specific enthalpy is below the prescribed range.

Temperature control system for temperature-controlling a room, comprising: a primary circuit (11); a secondary circuit; a first heat exchanger (1) with a primary side (10) and a secondary side (12), wherein the first heat exchanger (1) is configured to couple the primary circuit (11) and the secondary circuit, and wherein the primary circuit (11) is configured to extract heat from the secondary side (12) of the first heat exchanger (1) via the primary side (10) of the first heat exchanger, wherein the secondary circuit comprises: the secondary side (12) of the first heat exchanger (1); a manifold (2) which, in operation of the temperature control system, is arranged below (60) the secondary side of the first heat exchanger (1); a pump (3) which is coupled to the manifold (2);and a second heat exchanger (4) which, during operation of the temperature control system, is arranged in thermal interaction with the space (5) to be temperature controlled and is located above the collector (2); and a secondary fluid (50) which, during operation of the temperature control system, is arranged in the secondary circuit and is pressurized such that a phase change from a liquid secondary fluid to a vaporous secondary fluid takes place in the second heat exchanger (4) and a phase change from the vaporous secondary fluid to the liquid secondary fluid takes place in the secondary side (12) of the first heat exchanger (1).

This invention discloses a highly stable binary refrigeration compressor unit, comprising: a base, an evaporator mechanism, a condenser, a liquid receiver, a first compressor, a second compressor, an oil separator, a dryer filter, a first solenoid valve, a first outlet throttling valve, a first return throttling valve, a check valve, a plate heat exchanger, a second solenoid valve, a second outlet throttling valve, and a second return throttling valve. The evaporator mechanism is located on the outer right side of the base, and its interior includes adjustable evaporator components, adjustment components, and auxiliary heat exchange components. This highly stable binary refrigeration compressor unit can achieve a matching relationship between the compressor, condenser, throttling valve, and evaporator, providing an accurate basis combining theoretical calculations and practical application heat absorption and release coefficients, achieving optimal configuration of the entire refrigeration system. Furthermore, it can instantly adjust the evaporator's operating efficiency according to actual needs, achieving energy saving and noise reduction.

The cascade type cold and heat cogeneration system comprises a high-temperature-stage circulation unit and a low-temperature-stage circulation unit, and the high-temperature-stage circulation unit and the low-temperature-stage circulation unit are coupled through an intermediate heat exchanger; a cooling heat exchanger is arranged in front of a refrigerant inlet of a high-temperature-stage valve in the high-temperature-stage circulating unit; a low-temperature fluid inlet / outlet of a low-temperature heat exchanger in the low-temperature circulation unit communicates with a low-temperature fluid inlet / outlet of the cooling heat exchanger to form a circulation path; and the cooling heat exchanger is used for reducing the temperature of the high-temperature refrigerant passing through the cooling heat exchanger according to heat exchange between the flowing-in low-temperature-stage fluid and the high-temperature-stage refrigerant. In this way, the temperature of the high-temperature-stage refrigerant passing through the cooling heat exchanger can be reduced, local temperature limiting cooling is conducted on the high-temperature-stage valve, it is guaranteed that the high-temperature-stage valve operates within the normal temperature range, the service life of the high-temperature-stage valve is prolonged, and the structural stability of the high-temperature-stage valve is improved.

The invention provides a cascade heat pump and an adjusting method, and relates to the technical field of heat pumps. The cascade heat pump comprises a first-stage heat pump circulation system, a second-stage heat pump circulation system and a tail end pipeline, the first-stage heat pump circulation system comprises a first compressor, a hot side channel of a gas cooler, a hot side channel of a cascade heat exchanger, a first expansion valve and an evaporator which are sequentially connected to form a first refrigerant circulation; the second-stage heat pump circulation system comprises a second compressor, a condenser, a second expansion valve and a cold side channel of the cascade heat exchanger which are sequentially connected to form a second refrigerant circulation; the tail end pipeline is sequentially communicated with a cold side channel of the gas cooler and a cold side channel of the condenser in the conveying direction. According to the cascade type heat pump, due to the flow direction arrangement of the gas cooler and the tail end pipeline, the effective energy of the hot side channel and the cold side channel in the condenser in the heat exchange process can be effectively improved, the heating load of the condenser is effectively reduced, and therefore the overall performance coefficient of the cascade type heat pump is improved.

Methods for forming an improved, centralized refrigeration systems by: (a) providing an existing refrigeration circuit with an existing high GWP refrigerant; (b) disconnecting the fluid connection between the existing refrigerant liquid from the condenser and the evaporators; (c) disconnecting the fluid connection between the existing refrigerant vapor from the evaporators and the compressor suction; (d) establishing a new first refrigeration circuit comprising the compressor and the condenser; (e) establishing a new second refrigeration circuit comprising the evaporators by removing existing refrigerant from the evaporators and the disconnected conduits and replacing the removed refrigerant with a second refrigerant comprising at least 50% of R1234ze(E) and being Class Al and having an OEL greater than 400 and a GWP of about 150 or less; and thermally interconnecting the new first refrigeration circuit and the new second refrigeration circuit with an inter-circuit heat exchanger.

A refrigerant circuit includes a first compressor connected to a first suction pipe and a first discharge pipe and configured to compress a refrigerant, a second compressor connected to a second suction pipe and a second discharge pipe and configured to compress the refrigerant discharged from the first compressor, a radiator, and a high-pressure passage connecting the second discharge pipe and the radiator. A first oil drain passage guides an oil in the second compressor to one of the first suction pipe and an intermediate port of the first compressor, without via the high-pressure passage.

The invention relates to a thermoelectric heat pump including a heat exchanger block with a first channel for flow therethrough of a first heat transfer fluid such as a liquid medium and a separate second channel for flow therethrough of a second heat transfer fluid such as a liquid medium. The heat exchanger block includes a heat exchange cavity which is hydraulically separated by a partition into a first and a second sub-cavity which are connected to respectively the first and second channel and wherein the first heat transfer fluid in the first sub-cavity is in heat-exchanging contact with a first side of the partition and the second heat transfer fluid in the second sub-cavity is in heat-exchanging contact with a second side of the partition lying opposite the first side. The partition includes a thermoelectric element with a cold side and a hot side lying opposite thereto and at a distance therefrom. An outer peripheral edge extends between the cold and hot side, which thermoelectric element is configured to transport heat from the cold side to the hot side and wherein the cold side is in heat-exchanging contact with the first heat transfer fluid and wherein the hot side is in heat-exchanging contact with the second heat transfer fluid and wherein each channel is provided with a pump for pumping the respective heat transfer fluid through the channel.

The invention relates to a refrigerant circuit (10) comprising: - a first main loop (A1) comprising successively, according to the direction of refrigerant flow: - a first compressor (7), - a first heat exchanger (1) thermally coupled with a first external airflow (Fe1) to the passenger compartment of a motor vehicle, - a first expansion valve (31), - a second heat exchanger (2), - a second main loop (A2) comprising successively, according to the direction of refrigerant flow: - a second compressor (8), - a third heat exchanger (3) thermally coupled with a second external airflow (Fe2) to the passenger compartment of the vehicle, - a second expansion valve (32), - a fourth heat exchanger (4) thermally coupled with an internal airflow (Fi) to the passenger compartment of the motor vehicle.- a fifth heat exchanger (5) arranged jointly on the first main loop (A1) and on the second main loop (A2). Figure from the abstract: Figure 1,

The ultralow-temperature refrigerating system comprises a low-temperature system, a high-temperature system and a compressor, the low-temperature system comprises a low-temperature evaporator and a low-temperature condenser, the high-temperature system comprises a high-temperature evaporator and a high-temperature condenser, and the low-temperature condenser and the high-temperature evaporator are staggered to form an evaporative condenser. Pipe sets of the low-temperature condenser are arranged in a vertical S shape at equal intervals in the left-right direction, and pipe sets of the high-temperature evaporator are arranged in a horizontal S shape at equal intervals in the up-down direction, so that the cold exchange area of the low-temperature condenser and the high-temperature evaporator is increased, and the cold exchange efficiency of the low-temperature condenser and the high-temperature evaporator is improved; in cooperation with the structural design of a heat dissipation air inlet system, an exhaust hole, a condensation bin and the like, a single driving element is adopted for conducting heat dissipation on a compressor and a high-temperature condenser, then the refrigeration efficiency of a low-temperature system and a high-temperature system is improved, and operation energy consumption is reduced.

The utility model relates to the field of air refrigeration, and discloses a gas cooling system with a precooling function, which comprises a compressor I, a condenser I, a dry filter I, a throttling device I and a heat exchange device I which are sequentially connected end to end, the first compressor, the first condenser, the first drying filter, the first throttling device and the first heat exchange device form a first-stage refrigerating loop. The compressor II, the condenser II, the dryer II, the throttling device II and the heat exchanger II are sequentially connected end to end; the compressor II, the condenser II, the dryer II, the throttling device II and the heat exchanger II form a secondary refrigerating loop; wherein the condenser II is connected with the dryer II through a heat exchanger I; an air inlet pipeline bypasses the first heat exchanger, and the air outlet end is connected to the second heat exchanger. Air is pre-cooled by the first heat exchanger, enters the second heat exchanger for secondary heat exchange and then flows out from the air outlet end. The refrigerating system has the advantages of reliable refrigeration, low power, energy conservation and the like.

A transport climate control system and method for providing a first temperature for cooling a first conditioned space and a second temperature for cooling a second conditioned space. The transport climate control system including a first climate control system including a first compressor, a first condenser, a first expansion device, and a primary heat exchanger that is configured to thermally communicate with a coolant loop, a secondary climate control system including a second compressor, a cascaded heat exchanger, a second expansion device, and an evaporator; and the coolant loop having a coolant. The coolant loop is configured to thermally communicate with the primary heat exchanger, and the coolant loop is further configured to thermally communicate with one or more of the cascaded heat exchanger and the second conditioned space.

A high temperature heat pump apparatus is disclosed. The apparatus can include a first compression stage including a first evaporator that evaporates a first working fluid to form a first vapor, a first compressor that compresses the first vapor to increase the pressure of the first vapor, and a condenser that condenses the first vapor having increased pressure to deliver heat. The apparatus can include a second compression stage including a second evaporator that evaporates a second working fluid using the heat from the condenser of the first compression stage, where the second evaporator evaporates the second working fluid to form a second vapor, and a second compressor that compresses the second vapor to deliver high temperature heat.