CN205026983U - Take low ambient temperature air source heat pump system of cold loop - Google Patents

Abstract

The utility model relates to an air source heat pump refrigeration system, in particular to a low ambient temperature air source heat pump system with a supercooling circuit, which belongs to the technical field of air source heat pump systems. It includes a main circuit, a secondary circuit, a subcooling circuit and a one-way valve assembly. The first outlet of the supplementary air enthalpy increasing compressor is connected to the first port of the four-way reversing valve, and the second port of the four-way reversing valve is connected to the indoor reversing valve. The first port of the heat exchanger and the second port of the indoor heat exchanger are connected to the inlet port of the one-way valve assembly. The utility model increases the circulating flow rate of the refrigeration system in the low temperature environment of the air source heat pump through the optimized combination of the main circuit, the secondary circuit and the supercooling circuit; the high temperature refrigerant is introduced into the bottom of the outdoor heat exchanger, so that the outdoor heat exchanger can The temperature at the bottom is always higher than zero, and the bottom of the heat exchanger will not freeze. In winter, the condensed water and defrosting water of the outdoor heat exchanger can be discharged smoothly, avoiding the phenomenon that the unit cannot operate normally due to the accumulation of ice in a cold and high humidity environment.

Description

Low ambient temperature air source heat pump system with subcooling circuit

technical field

The utility model relates to an air source heat pump refrigeration system, in particular to a low ambient temperature air source heat pump system with a supercooling circuit, which belongs to the technical field of air source heat pump systems.

Background technique

At present, many areas in northern China still use boilers for heating. The pollutants emitted by boilers burning coal at low altitudes are one of the important killers of smog and PM2.5 in northern areas. To completely control the smog in the north, eliminating small coal-fired boilers is the fundamental way out. Encouraging and supporting the development of new energy, energy-saving and environmental protection industries such as the air source heat pump industry is one of the main ways to solve the smog in the northern region.

However, when air source heat pumps are extended to cold areas such as the Yellow River Basin, North China, and Northwest China (the heating design temperature range is -5 to -20°C), they encounter problems such as serious attenuation of heating heat and low energy efficiency ratio at low ambient temperatures; The temperature is lower than zero degrees Celsius for a long time. If the defrosting water generated during the defrosting of the unit in winter cannot be discharged in time, it will cause the bottom of the outdoor heat exchanger to freeze, and the unit will not be able to operate normally due to the accumulation of ice.

Contents of the invention

The purpose of this utility model is to overcome the above disadvantages, thereby providing a low ambient temperature air source heat pump system with a supercooling circuit, which can not only suppress the attenuation rate of the heating capacity of the air source heat pump in a low temperature environment, but also solve the problem of heating in winter The outdoor heat exchanger freezes in low-temperature and high-humidity environments, and at the same time can improve the cooling performance coefficient during cooling in summer.

According to the technical solution provided by the utility model, the low ambient temperature air source heat pump system with a subcooling circuit includes a main circuit, a secondary circuit, a subcooling circuit and a one-way valve assembly. Directional valve, indoor heat exchanger, liquid storage, outdoor heat exchanger and gas-liquid separator; the secondary circuit includes an economizer, an electronic expansion valve and a gas supply pipe, which is characterized in that the first outlet of the gas supplement enthalpy increasing compressor is connected The first port of the reversing valve is connected, the second port of the four-way reversing valve is connected to the first port of the indoor heat exchanger, and the second port of the indoor heat exchanger is connected to the inlet port of the one-way valve assembly;

The one-way valve assembly includes a first one-way valve, a second one-way valve, a third one-way valve and a fourth one-way valve, the pipeline after the first one-way valve and the third one-way valve are connected in series with the first one-way valve After the second one-way valve and the fourth one-way valve are connected in series, the pipelines are connected in parallel;

The first inlet of the accumulator is connected with the first one-way valve and the third one-way valve, the first outlet of the accumulator is connected to the first inlet of the economizer through the subcooling circuit, and the first outlet of the economizer is connected through the first The branch is connected to the first inlet of the thermal expansion valve, and the first outlet of the thermal expansion valve is connected to the second one-way valve and the fourth one-way valve;

The outlet end of the one-way valve assembly is connected to the first port of the outdoor heat exchanger, the second port of the outdoor heat exchanger is connected to the fourth port of the four-way reversing valve, and the third port of the four-way reversing valve is connected to the gas-liquid separator The first inlet of the gas-liquid separator, the first outlet of the gas-liquid separator is connected to the first inlet of the gas-supplementing enthalpy increasing compressor;

The first outlet of the economizer is connected to the first inlet of the electronic expansion valve through the second branch, the first outlet of the electronic expansion valve is connected to the second inlet of the economizer, and the second outlet of the economizer is connected to the supplementary air enthalpy increase compression through the air supply pipe Air supply port of the machine.

Further, the pipe body of the subcooling circuit passes through the bottom of the outdoor heat exchanger.

Further, a solenoid valve connected in parallel with the thermal expansion valve is provided beside the thermal expansion valve.

Compared with the prior art, the utility model has the following advantages:

The utility model optimizes the combination of the main loop, the secondary loop and the supercooling loop. First, it increases the circulation flow rate of the refrigeration system in the low-temperature environment of the air source heat pump; The temperature at the bottom of the outdoor heat exchanger is always higher than zero at low temperature, and the bottom of the heat exchanger will not freeze. In winter, the condensed water and defrosting water of the outdoor heat exchanger can be discharged smoothly, avoiding the damage caused by the accumulation of ice in the cold and high humidity environment. Third, if the refrigerant first passes through the economizer and then enters the outdoor heat exchanger, it will lead to the problem that the refrigerant that has been supercooled will be heated again in the outdoor heat exchanger during cooling, and the cooling The flow direction of the refrigerant is set to first pass through the outdoor heat exchanger and then enter the economizer, which effectively avoids the above problems, and at the same time increases the subcooling degree of the refrigerant during cooling, and improves the cooling performance coefficient.

Description of drawings

Fig. 1 is a front view of the utility model.

Explanation of reference numerals: 1-compressor for supplementing air and increasing enthalpy, 2-four-way reversing valve, 3-indoor heat exchanger, 4-liquid receiver, 5-outdoor heat exchanger, 6-gas-liquid separator, 7 -First one-way valve, 8-Second one-way valve, 9-Third one-way valve, 10-Fourth one-way valve, 11-Supercooling circuit, 12-Thermal expansion valve, 13-Solenoid valve, 14- Economizer, 15-electronic expansion valve, 16-air supply pipe.

detailed description

Below the utility model will be further described in conjunction with the embodiment in the accompanying drawing:

As shown in Figure 1, the utility model mainly includes a main circuit, a secondary circuit, a supercooling circuit 11 and a one-way valve assembly, and the main circuit includes a compressor 1 for supplementing air and increasing enthalpy, a four-way reversing valve 2, and an indoor heat exchanger 3 , liquid receiver 4, outdoor heat exchanger 5 and gas-liquid separator 6;

The first outlet of the air supplement enthalpy increasing compressor 1 is connected to the first port of the four-way reversing valve 2, the second port of the four-way reversing valve 2 is connected to the first port of the indoor heat exchanger 3, and the The second port is connected to the inlet port of the one-way valve assembly.

The one-way valve assembly includes a first one-way valve 7, a second one-way valve 8, a third one-way valve 9 and a fourth one-way valve 10, and the first one-way valve 7 and the third one-way valve 9 are connected in series The last pipeline is connected in parallel with the pipeline after the second one-way valve 8 and the fourth one-way valve 10 are connected in series.

The first inlet of the accumulator 4 is connected to the first one-way valve 7 and the third one-way valve 9, the first outlet of the accumulator 4 is connected to the first inlet of the economizer 14 through the subcooling circuit 11, and the economizer 14 The first outlet of the thermal expansion valve 12 is connected to the first inlet of the thermal expansion valve 12 through the first branch, and the first outlet of the thermal expansion valve 12 is connected to the second one-way valve 8 and the fourth one-way valve 10 .

The outlet end of the one-way valve assembly is connected to the first port of the outdoor heat exchanger 5 , and the second port of the outdoor heat exchanger 5 is connected to the fourth port of the four-way reversing valve 2 . The third port of the four-way reversing valve 2 is connected to the first inlet of the gas-liquid separator 6 , and the first outlet of the gas-liquid separator 6 is connected to the first inlet of the gas-supplementing enthalpy increasing compressor 1 .

The first outlet of the economizer 14 is connected to the first inlet of the electronic expansion valve 15 through the second branch, the first outlet of the electronic expansion valve 15 is connected to the second inlet of the economizer 14, and the second outlet of the economizer 14 passes through the air supply pipe 16 Connect to the air supply port of air supply enthalpy increasing compressor 1.

The tube body of the subcooling circuit 11 passes through the bottom of the outdoor heat exchanger 5 , and the refrigerant in the subcooling circuit 11 increases the temperature at the bottom of the outdoor heat exchanger 5 while reducing the temperature of the refrigerant in the subcooling circuit tube.

A solenoid valve 13 connected in parallel with the thermal expansion valve 12 is arranged beside the thermal expansion valve 12 .

There are two ways to divide the main circuit through the economizer: the first way is that the main circuit refrigerant first passes through the economizer and then divides the flow. The first branch is connected to the thermal expansion valve assembly, and the second branch is connected to the electronic expansion valve; The second way is to divide into two branches before entering the economizer, the first branch is connected to the economizer, and the second branch is connected to the electronic expansion valve.

The working principle of the utility model is: in the heating mode, the high-temperature and high-pressure refrigerant flows from the air-supplementing enthalpy-increasing compressor through the four-way reversing valve, cools in the indoor heat exchanger, and flows into the liquid storage through the one-way valve , the refrigerant flowing out of the liquid receiver passes through the cold circuit and passes through the bottom of the outdoor heat exchanger, which increases the temperature at the bottom of the outdoor heat exchanger and reduces the temperature of the refrigerant in the pipe. After passing through the economizer, it is divided into two branches. The first branch flows into the thermal expansion valve, and the second branch flows into the electronic expansion valve. The refrigerant flowing out from the bottom of the outdoor heat exchanger is throttling in the economizer and the electronic expansion valve. The heat exchange of the final low-temperature refrigerant not only increases the subcooling degree of the refrigerant in the main circuit, but also heats the superheating degree of the refrigerant in the secondary circuit. , when the refrigerant passes through the thermal expansion valve, the solenoid valve is in a closed state, the main circuit refrigerant can only pass through the thermal expansion valve, and the refrigerant that has been throttled by the thermal expansion valve enters the outdoor heat exchanger through the check valve for heat exchange After the heat exchange is completed, it enters the gas-liquid separator through the four-way reversing valve. If the refrigerant is a gas-liquid mixture when entering the gas-liquid separator, the liquid is separated at the bottom of the gas-liquid separator 5, and the gaseous refrigerant passes through The suction port enters into the air-supplementing enthalpy-enhancing compressor to complete a heating cycle.

In the cooling mode, the high-temperature and high-pressure refrigerant flows from the gas-supplementing enthalpy-enhancing compressor through the four-way reversing valve, cools in the outdoor heat exchanger, and flows into the liquid receiver through the one-way valve, and the refrigerant flowing out of the liquid receiver After the cold circuit passes through the bottom of the outdoor heat exchanger, the temperature of the refrigerant in the pipe is lowered again; then it is divided into two branches after passing through the economizer, the first branch flows into the thermal expansion valve, the second branch flows into the electronic expansion valve, and the refrigerant from the outdoor The refrigerant flowing out of the bottom of the heater exchanges heat with the low-temperature refrigerant throttled by the electronic expansion valve in the economizer, which not only increases the subcooling degree of the refrigerant in the main circuit, but also heats the superheating degree of the refrigerant in the secondary circuit. The refrigerant inside enters the air supply port of the air supply enthalpy increasing compressor through the air supply pipe. When the refrigerant passes through the thermal expansion valve assembly, the solenoid valve is in a closed state, and the main circuit refrigerant can only pass through the thermal expansion valve and the thermal expansion valve section. The refrigerant after flow enters the outdoor heat exchanger through the one-way valve for heat exchange. After the heat exchange is completed, it enters the gas-liquid separator through the four-way reversing valve. If the refrigerant is a gas-liquid mixture when entering the gas-liquid separator, The liquid is separated at the bottom of the gas-liquid separator, and the gaseous refrigerant enters the gas-supplementing enthalpy-enhancing compressor through the suction port to complete a refrigeration cycle.

The main circuit of the utility model has two ways of shunting when passing through the economizer: the first way is that the main circuit refrigerant first passes through the economizer and then shunts, the first branch is connected to the thermal expansion valve, and the second branch is connected to the electronic Expansion valve; the second way is to divide into two branches before entering the economizer, the first branch is connected to the economizer, and the second branch is connected to the electronic expansion valve. The utility model optimizes the combination of the main loop, the secondary loop and the supercooling loop. First, it increases the circulation flow rate of the refrigeration system in the low-temperature environment of the air source heat pump; The temperature at the bottom of the outdoor heat exchanger is always higher than zero at low temperature, and the bottom of the heat exchanger will not freeze. In winter, the condensed water and defrosting water of the outdoor heat exchanger can be discharged smoothly, avoiding the damage caused by the accumulation of ice in the cold and high humidity environment. Third, if the refrigerant first passes through the economizer and then enters the outdoor heat exchanger, it will lead to the problem that the refrigerant that has been supercooled will be heated again in the outdoor heat exchanger during cooling, and the cooling The flow direction of the refrigerant is set to first pass through the outdoor heat exchanger and then enter the economizer, which effectively avoids the above problems, and at the same time increases the subcooling degree of the refrigerant during cooling, and improves the cooling performance coefficient.

Claims (3)

1. one kind with the low ambient temperature air source heat pump system of cold loop, comprise major loop, subloop, cross cold loop (11) and check valve assembly, major loop comprises tonifying Qi and increases enthalpy compressor (1), four-way change-over valve (2), indoor heat exchanger (3), reservoir (4), outdoor heat exchanger (5) and gas-liquid separator (6); Subloop comprises economizer (14), electric expansion valve (15) and blowdown pipe (16), it is characterized in that: tonifying Qi increases the first port of the first outlet connection four-way change-over valve (2) of enthalpy compressor (1), second port of four-way change-over valve (2) connects the first port of indoor heat exchanger (3), and the second port of indoor heat exchanger (3) connects the arrival end of check valve assembly;

Described check valve assembly comprises the first check valve (7), the second check valve (8), the 3rd check valve (9) and the 4th check valve (10), and the pipeline after the pipeline after the first check valve (7), the 3rd check valve (9) are connected in series and the second check valve (8), the 4th check valve (10) are connected in series is connected in parallel;

First entrance of reservoir (4) is connected with between the first check valve (7) and the 3rd check valve (9), first outlet of reservoir (4) connects economizer (14) first entrance by crossing cold loop (11), first outlet of economizer (14) connects the first entrance of heating power expansion valve (12) by the first branch road, the first outlet of heating power expansion valve (12) is connected with between the second check valve (8), the 4th check valve (10);

First port of the port of export junction chamber external heat exchanger (5) of check valve assembly, second port of outdoor heat exchanger (5) connects the 4th port of four-way change-over valve (2), 3rd port of four-way change-over valve (2) connects the first entrance of gas-liquid separator (6), and the first outlet of gas-liquid separator (6) connects the first entrance that tonifying Qi increases enthalpy compressor (1);

First outlet of economizer (14) connects the first entrance of electric expansion valve (15) by the second branch road, first outlet of electric expansion valve (15) connects the second entrance of economizer (14), and the second outlet of economizer (14) connects by blowdown pipe (16) gas supplementing opening that tonifying Qi increases enthalpy compressor (1).

2. as claimed in claim 1 with the low ambient temperature air source heat pump system of cold loop, it is characterized in that: the described bottom of body through outdoor heat exchanger (5) crossing cold loop (11).

3. as claimed in claim 1 with the low ambient temperature air source heat pump system of cold loop, it is characterized in that: described heating power expansion valve (12) is other is provided with the magnetic valve (13) be connected in parallel with heating power expansion valve (12).