CN102927628B - A kind of synchronous brand new air processing group that cold-peace is overheated excessively - Google Patents

Abstract

The invention discloses a synchronous supercooling and superheating fresh air air handling unit, which comprises a compressor, a four-way reversing valve, an outdoor processing unit heat exchanger, a two-way expansion valve and an indoor air supply unit heat exchanger, and a compressor. The intake end and the exhaust end are respectively connected to two opposite ports on the four-way reversing valve, and the cooling inlet of the heat exchanger of the outdoor processing unit and the cooling outlet of the heat exchanger of the indoor air supply unit are respectively connected to the four-way reversing valve. The other two opposite interfaces are connected, and the cooling outlet of the heat exchanger of the outdoor processing unit is connected with the cooling inlet of the heat exchanger of the indoor air supply unit through the bidirectional expansion valve. The equipment of the present invention effectively solves the problem of loss of obtained subcooling degree, enhances the stability and reliability of the expansion valve, avoids wet compression of the compressor, and can improve the safety, reliability and working energy efficiency ratio of the unit.

Description

A fresh air air handling unit with synchronous subcooling and superheating

technical field

The invention relates to a fresh air handling unit, in particular to a fresh air handling unit with synchronous supercooling and overheating, belonging to the technical field of building environment and equipment engineering.

Background technique

The Fresh Air Handling Unit is a device that uses direct evaporative cooling or heat pump heating to deal with fresh air, and directly provides centralized processing of fresh air to confined spaces, rooms or areas through air ducts. It is widely used in pharmaceuticals, chemicals, Food, electronics, metallurgy and other fields. At present, the direct evaporative fresh air air handling unit is usually composed of a compressor, a four-way reversing valve, an outdoor processing unit heat exchanger, an expansion valve and an indoor air supply unit heat exchanger. Under this condition, the heat exchange generated by the phase change of the refrigerant with the external environment is used to improve the indoor temperature and meet the needs of normal life and work.

At present, the vast majority of direct evaporative fresh air air handling units do not have subcooling equipment, and a small number of systems are equipped with subcoolers. Often due to the unreasonable layout of subcoolers, the actual supercooling effect of the system is greatly reduced, and it is difficult to improve the system performance. energy efficiency ratio. In addition, it is difficult to ensure a certain degree of superheat for the refrigerant at the inlet of the compressor, which greatly affects the working stability of the compressor.

Invention patent CN101576297 B A new air handling unit with large supercooling degree. In the refrigeration cycle, the refrigerant enters the heat exchanger of the outdoor processing unit (in this case, the condenser) and the air heat exchange and condenses, and then enters into a high-pressure liquid storage The refrigerant coming out of the high-pressure liquid storage tank enters the subcooler for subcooling treatment, thereby increasing the subcooling degree of the refrigerant.

Due to the uneven flow field on the air side, the heat exchange of each branch of the heat exchanger of the outdoor processing unit is also uneven, some branches have good heat exchange effect, while some branch heat exchange effect is not good. In the branch with good heat exchange effect, the refrigerant is fully condensed, and a relatively large degree of refrigerant subcooling is obtained; in the branch with poor heat exchange effect, the refrigerant cannot be fully condensed, and the degree of subcooling of the refrigerant is not high or not supercooling. The branches with good heat exchange effect and large subcooling degree and the branches with poor heat exchange effect and small subcooling degree merge into one road and enter the high-pressure liquid storage tank together. Due to the gas-liquid two-phase action of the high-pressure liquid storage tank, the subcooling degree of the refrigeration cycle is suppressed together. Consumed by interaction.

After the refrigerant comes out of the high-pressure liquid storage tank, it enters the subcooler to obtain a certain degree of subcooling, which can be said to be a last resort.

Therefore, the invention patent CN101576297 B, a fresh air air handling unit with large subcooling degree, on the one hand sacrifices the refrigerant supercooling capacity of the branch circuit with good heat exchange, on the other hand, it must increase the area of the subcooler to make up for or regain The subcooling degree required by the cooling unit reduces the heat exchange effect of the outdoor processing unit heat exchanger and reduces the cooling energy efficiency ratio; secondly, it increases the area of the subcooler and increases the initial investment of the equipment.

Similarly, in the heating cycle, the refrigerant enters the heat exchanger of the indoor air supply unit (in this case, the condenser) to exchange heat and condense with the air, and then merges into one path and then directly enters the expansion valve. At this time, it is difficult to ensure a certain degree of subcooling of the refrigerant, which is not conducive to the stable operation of the expansion valve.

In addition, it is worth noting that the superheat of the refrigerant imported by the compressor often needs to be controlled at 5°C to 11°C: if the superheat is too low, the compressor will easily form wet compression, which will affect the stability and safety of the refrigeration system; if the superheat is too high , The exhaust temperature of the compressor is too high, the input power of the compressor increases, the performance of the fresh air air handling unit decreases, and its stability and safety cannot be guaranteed. Invention patent CN101576297 B is a fresh air air handling unit with large supercooling degree, which does not consider the problem of refrigerant superheat degree control.

Contents of the invention

Technical problem: In view of the defects existing in the prior art, the present invention provides a method that can improve the energy efficiency ratio of operation, effectively increase the supercooling degree of the unit and control the superheating degree of the unit, improve the working performance and safety performance of the unit, and improve the operating efficiency of the unit. Synchronized subcooling and superheating fresh air air handling units.

Technical solution: The fresh air air handling unit with synchronous subcooling and superheating of the present invention includes a compressor, a four-way reversing valve, an outdoor processing unit heat exchanger, a two-way expansion valve and an indoor air supply unit heat exchanger, and the compressor The intake end and the exhaust end are respectively connected to two opposite ports on the four-way reversing valve, and the cooling inlet of the heat exchanger of the outdoor processing unit and the cooling outlet of the heat exchanger of the indoor air supply unit are respectively connected to the four-way reversing valve. The other two relative interfaces are connected, and the cooling outlet of the heat exchanger of the outdoor processing unit is connected with the cooling inlet of the heat exchanger of the indoor air supply unit through the bidirectional expansion valve; the heat exchanger of the outdoor processing unit includes an outdoor superheater, an outdoor multi-branch road heat exchanger, high-pressure liquid storage tank, outdoor subcooler and outdoor fan. The branch heat exchangers are parallel, the cooling outlet of the outdoor superheater is connected to the cooling inlet of the outdoor multi-branch heat exchanger, the cooling outlet of the heat exchange coil of the branch with the worst heat exchange effect in the outdoor multi-branch heat exchanger is connected to The cooling inlet connection of the high-pressure liquid storage tank, the cooling outlet of the high-pressure liquid storage tank and the cooling outlet of the heat exchange coil of other branches in the outdoor multi-branch heat exchanger are connected through pipelines and then jointly with the cooling of the outdoor subcooler Inlet connection, the cooling inlet of the outdoor superheater is the cooling inlet of the heat exchanger of the outdoor processing unit, and the cooling outlet of the outdoor subcooler is the cooling outlet of the heat exchanger of the outdoor processing unit.

In the present invention, the heat exchanger of the indoor air supply unit includes an indoor subcooler, an indoor multi-branch heat exchanger, an indoor superheater and an indoor fan, and the indoor subcooler and the indoor superheater are respectively arranged in the heat exchanger of the indoor air supply unit. The positions with the best and worst heat exchange effects in the center are parallel to the indoor multi-branch heat exchanger, the cooling outlet of the indoor subcooler is connected to the cooling inlet of the indoor multi-branch heat exchanger, and the indoor multi-branch heat exchanger The cooling outlet is connected to the cooling inlet of the indoor superheater, the cooling inlet of the indoor supercooler is the cooling inlet of the heat exchanger of the indoor air supply unit, and the cooling outlet of the indoor superheater is the cooling outlet of the heat exchanger of the indoor air supply unit.

The refrigeration cycle is as follows: the refrigerant becomes a high-temperature and high-pressure gas after passing through the compressor, and enters the heat exchanger of the outdoor processing unit (in this case, the condenser) to condense through the action of the four-way reversing valve. In the heat exchanger of the outdoor processing unit, the refrigerant gas enters the outdoor multi-branch heat exchanger to exchange heat with the air after passing through the outdoor superheater; the refrigerant in the branch with the worst heat transfer effect enters the high-pressure liquid storage tank, and then with the rest After the branches are merged, they pass through the common outdoor subcooler located in the branch with the best heat exchange effect for subcooling and heat exchange. Afterwards, the refrigerant with a large subcooling degree is throttled through the two-way expansion valve, and enters the heat exchanger of the indoor air supply unit (the evaporator at this time) for heat exchange. In the heat exchanger of the indoor air supply unit, the refrigerant liquid enters the indoor multi-branch heat exchanger through the indoor subcooler to exchange heat with the air, and then undergoes superheating treatment through the common superheater located in the branch with the worst heat transfer effect, to obtain A certain degree of superheat. After completing the heat exchange, the refrigerant returns to the compressor through a port of the four-way reversing valve, so that the entire refrigeration process is completed.

The heating cycle is as follows: the refrigerant becomes a high-temperature and high-pressure gas after passing through the compressor, and enters the indoor air supply unit heat exchanger (condenser at this time) for heat exchange through the action of the four-way reversing valve. In the heat exchanger of the indoor air supply unit, the refrigerant gas enters the indoor multi-branch heat exchanger through the indoor superheater to exchange heat with the air, and then passes through the common outdoor subcooler located in the branch with the best heat exchange effect for subcooling exchange. hot. Afterwards, the refrigerant with a large subcooling degree is throttled through the two-way expansion valve, and enters the heat exchanger of the outdoor processing unit (the evaporator at this time) for heat exchange. In the heat exchanger of the outdoor processing unit, the refrigerant liquid is divided into two paths after being heat-exchanged by the outdoor subcooler, and one path passes through the high-pressure liquid storage tank and then enters the heat exchange of the branch with the worst heat exchange effect in the outdoor multi-branch heat exchanger. The heat is exchanged in the coil, and the other path directly enters the outdoor multi-branch heat exchanger to exchange heat with the air, and then passes through the common superheater located in the branch with the worst heat exchange effect for superheating treatment to obtain a certain degree of superheat . After completing the heat exchange, the refrigerant returns to the compressor through a port of the four-way reversing valve, so that the entire heating process is completed.

During the refrigeration process, the refrigerant in the branch with the worst heat exchange effect in the outdoor multi-branch heat exchanger flows through the high-pressure liquid storage tank, and then is summed up with other branches, and passes through the outdoor area where the air heat exchange effect is the best. subcooler. In this way, the heat exchange effect in the outdoor multi-branch heat exchanger is good, and the refrigerant that has obtained a relatively large subcooling degree can be fully utilized. temperature and undergoes the gas-liquid two-phase action of the liquid receiver, and then passes through a section of the outdoor subcooler coil that is located at the best heat effect, so that the subcooling degree of the unit can be maximized and can be appropriately reduced The heat exchange area of the outdoor subcooler reduces the initial investment of the unit. Similarly, during the heating process, after the refrigerant passes through the indoor multi-branch heat exchanger for heat exchange, it enters the coil section of the indoor subcooler located at the best heat exchange effect for subcooling and heat exchange to obtain a certain degree of subcooling. This ensures the high efficiency and stability of the two-way expansion valve. The reason why the subcooler should be placed in the place where the multi-branch condensing coil has the best heat exchange effect with the air is to increase the subcooling degree of the unit and ensure that the subcooling degree of the refrigerant is at least greater than 3°C, thereby ensuring Stability of two-way expansion valve and high cooling/heating effect.

During the cooling process, the refrigerant flows through the indoor multi-branch heat exchanger, and then enters the indoor superheater located at the place where the air heat exchange effect is the worst, so that it can be mixed evenly and its superheat can be controlled, so as to ensure that the refrigerant imported by the compressor is overheated. The temperature is between 5°C and 11°C, which improves the stability and safety of the unit. Similarly, after the refrigerant flows through the outdoor multi-branch heat exchanger during the heating process, it also passes through a section of the outdoor superheater coil section located at the place where the air heat exchange effect is the worst. The reason why the superheater is placed in the place where the air heat exchange effect is the worst in the heat exchanger is to ensure that the unit has a certain degree of superheat. The degree of superheat is generally greater than 5°C to ensure the safe operation of the compressor, but it must be controlled. The greater the degree of superheat, the better. Generally, it should not exceed 11°C. That is to say, the degree of superheat of the refrigeration system needs to be controlled within the range of 5-11°C. Inside.

Beneficial effects: The present invention provides a synchronous supercooling and superheating fresh air air handling unit, which has the following advantages compared with the prior art:

(1) Both the indoor air supply unit heat exchanger and the outdoor processing unit heat exchanger include a subcooler. The subcooler is located in the branch circuit with the best heat exchange effect with the air in the heat exchanger assembly. The common subcooler coil section greatly improves the heat exchange effect of the heat exchanger assembly and ensures the subcooling degree of the refrigerant. The large subcooling degree in the heating process can ensure that there are no air bubbles in the refrigerant when it passes through the expansion valve, enhance the stability and reliability of the two-way expansion valve, and improve the heat exchange effect of the indoor air supply heat exchanger and increase the heating capacity. . The cooling process not only improves the heat exchange effect of the heat exchanger of the outdoor processing unit, increases the cooling capacity of the unit, improves the cooling energy efficiency ratio (EER), but also reduces the area of the subcooler and reduces the initial investment of the equipment. At the same time, the performance of the two-way expansion valve is also guaranteed.

(2) Both the heat exchanger of the indoor air supply unit and the heat exchanger of the outdoor processing unit include a superheater. The superheater is located in the branch of the heat exchanger assembly with the worst heat exchange effect with the air. The superheater effectively controls the superheat of the refrigerant to ensure that the superheat of the refrigerant imported from the compressor is between 5°C and 11°C, avoiding the wet compression of the compressor. The performance of the refrigeration system is improved, and its stability and safety are also guaranteed.

(3) During the refrigeration process, the branch with the worst heat transfer effect in the outdoor multi-branch heat exchanger is selectively made to enter the high-pressure liquid storage tank, and then merge with the other branches to pass through the outdoor processing unit for exchange. The subcooler in the heater performs subcooling and heat exchange with the subcooler located in the air with the best heat exchange effect, which avoids the suppression of the subcooling degree of the refrigeration cycle due to the gas-liquid two-phase action of the high-pressure liquid storage tank, and effectively improves the outdoor processing unit. The heat exchange effect of the heat exchanger improves the subcooling degree of the refrigerant.

Description of drawings

Fig. 1 is a schematic diagram of a fresh air air handling unit disclosed in the prior art;

Fig. 2 is the schematic diagram of the fresh air air handling unit of synchronous supercooling and superheating of the present invention;

3 is a structural diagram of an outdoor processing unit heat exchanger according to an embodiment of the present invention;

Fig. 4 is the vector diagram of the air wind velocity field of the heat exchanger of the outdoor processing unit according to the embodiment of the present invention;

Fig. 5 is the structural diagram of the heat exchanger of the outdoor processing unit of Embodiment 2 of the present invention;

Fig. 6 is the vector diagram of the air wind velocity field of the heat exchanger of the outdoor processing unit in Embodiment 2 of the present invention;

Fig. 7 is a structural diagram of the heat exchanger of the outdoor processing unit in Embodiment 3 of the present invention;

Fig. 8 is a vector diagram of the air wind velocity field of the heat exchanger of the outdoor processing unit in Embodiment 3 of the present invention;

Fig. 9 is a structural diagram of an indoor air supply unit heat exchanger according to an embodiment of the present invention;

Fig. 10 is a vector diagram of the air velocity field of an indoor air supply unit heat exchanger according to an embodiment of the present invention;

Fig. 11 is a structural diagram of the heat exchanger of the indoor air supply unit in Embodiment 2 of the present invention;

Fig. 12 is the vector diagram of the air velocity field of the heat exchanger of the indoor air supply unit in Embodiment 2 of the present invention;

Fig. 13 is a structural diagram of the heat exchanger of the indoor air supply unit in Embodiment 3 of the present invention;

Fig. 14 is a vector diagram of the air velocity field of the heat exchanger of the indoor air supply unit in Embodiment 3 of the present invention.

In the figure: 1-compressor; 2-four-way reversing valve; 3-outdoor processing unit heat exchanger; 31-outdoor superheater; 32-outdoor multi-branch heat exchanger; 321-outdoor multi-branch heat exchanger Branch coil with the worst medium effect; 33-outdoor subcooler; 34-high pressure liquid storage tank; 35-outdoor fan; 4 two-way expansion valve; 5-indoor air supply unit heat exchanger; 51-indoor subcooler; 52-indoor multi-branch heat exchanger; 53-indoor superheater; 54-indoor fan.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

The fresh air air handling unit with synchronous supercooling and superheating of the present invention comprises a compressor 1, a four-way reversing valve 2, an outdoor processing unit heat exchanger 3, a two-way expansion valve 4 and an indoor air supply unit heat exchanger 5, and the compression The intake end and the exhaust end of the machine 1 are respectively connected to two opposite ports on the four-way reversing valve 2, and the cooling inlet of the outdoor processing unit heat exchanger 3 and the cooling outlet of the indoor air supply unit heat exchanger 5 are respectively connected to the The other two relative interfaces on the four-way reversing valve 2 are connected, and the cooling outlet of the outdoor processing unit heat exchanger 3 is connected with the cooling inlet of the indoor air supply unit heat exchanger 5 through the two-way expansion valve 4; The heater 3 includes an outdoor superheater 31, an outdoor multi-branch heat exchanger 32, a high-pressure liquid storage tank 34, an outdoor subcooler 33 and an outdoor fan 35, and the outdoor subcooler 33 and the outdoor superheater 31 are respectively arranged in the outdoor processing unit The positions with the best and worst heat exchange effects in the heat exchanger are parallel to the outdoor multi-branch heat exchanger 32, the cooling outlet of the outdoor superheater 31 is connected to the cooling inlet of the outdoor multi-branch heat exchanger 32, and the outdoor multi-branch heat exchanger The cooling outlet of the heat exchange coil 321 of the branch with the worst heat exchange effect in the heat exchanger 32 is connected to the cooling inlet of the high-pressure liquid storage tank 34, and the cooling outlet of the high-pressure liquid storage tank 34 is connected to the outdoor multi-branch heat exchanger The cooling outlets of the heat exchange coils of other branches in 32 are connected with the cooling inlet of the outdoor subcooler 33 after being connected by pipelines. The heat exchange coils of other branches here refer to the outdoor multi-branch heat exchange The heat exchange coils in the device 32 except the heat exchange coil 321 of the branch with the worst heat exchange effect. The cooling inlet of the outdoor superheater 31 is the cooling inlet of the heat exchanger 3 of the outdoor processing unit, the cooling outlet of the outdoor subcooler 33 is the cooling outlet of the heat exchanger 3 of the outdoor processing unit, and the outdoor fan 35 is used to transfer the refrigerant and Air enhances heat transfer.

In another embodiment of the present invention, the heat exchanger 5 of the indoor air supply unit includes an indoor subcooler 51, an indoor multi-branch heat exchanger 52, an indoor superheater 53, and an indoor fan 54. The heat exchangers 53 are respectively arranged in the best and worst positions of the heat exchanger of the indoor air supply unit and parallel to the indoor multi-branch heat exchanger 52. The cooling outlet of the indoor subcooler 51 and the indoor multi-branch heat exchange The cooling inlet of the indoor multi-branch heat exchanger 52 is connected, the cooling outlet of the indoor multi-branch heat exchanger 52 is connected with the cooling inlet of the indoor superheater 53, and the cooling inlet of the indoor supercooler 51 is the cooling inlet of the heat exchanger 5 of the indoor air supply unit. The cooling outlet of the indoor superheater 53 is the cooling outlet of the heat exchanger 5 of the indoor air supply unit, and the indoor fan 54 is used to enhance heat exchange between the refrigerant and the air.

The present invention is a fresh air air handling unit with synchronous supercooling and superheating. The outdoor processing unit heat exchanger 3 and the indoor air supply unit heat exchanger 5 have three air outlet positions: upper air outlet, lower air outlet, and flat air outlet. , and the corresponding vector diagram of the air wind velocity field is an upper triangle, a lower triangle, and a middle triangle . Based on this, there are three kinds of heat exchange conditions in the heat exchange coil branches in the heat exchanger 3 of the outdoor processing unit and the heat exchanger 5 of the indoor air supply unit. In this way, at least 3×3=9 combinations can be corresponded. These 9 combinations are respectively the upper air outlet of the heat exchanger fan 35 of the outdoor processing unit corresponding to the upper air outlet, lower air outlet, and flat outlet air of the indoor air supply unit heat exchanger fan 54; the outdoor processing unit heat exchanger fan 35 is lower The air outlets respectively correspond to the upper air outlet, lower air outlet, and flat outlet air of the heat exchanger fan 54 of the indoor air supply unit; , Downward out of the wind, flat out of the wind.

Embodiment 1 of the present invention is the first type of outdoor processing unit heat exchanger 3 and indoor air supply unit heat exchanger 5 . Both the fans of the heat exchanger 3 of the outdoor processing unit and the heat exchanger 5 of the indoor air supply unit are upward air outlets, and the distribution vector diagrams of their wind speeds conform to the upper triangle. When the structure of the heat exchanger is determined, this specific air supply mode has a one-to-one correspondence with the upper triangle distribution vector diagram of the wind speed. It can be seen from the upper triangular wind speed distribution vector diagram that the wind speed at the upper part of the heat exchanger is high, so when the external air sweeps across the upper branch of the heat exchanger, the effect of forced heat exchange with the refrigerant in the tube is good. The uppermost branch of the heat exchanger 5 of the device 3 and the indoor air supply unit is set as an outdoor subcooler 33 and an indoor subcooler 51; When the heat exchange effect is poor with the refrigerant in the pipe, the present invention respectively sets the indoor superheater 53 and the outdoor superheater 31 as the indoor superheater 53 and the outdoor superheater 31, and the outdoor superheater 31 respectively. A branch adjacent to the outdoor superheater 31 in the multi-branch heat exchanger 32 is the branch 321 with the worst heat exchange effect. In the cooling condition, the refrigerant becomes a high-temperature and high-pressure gas after passing through the compressor 1, and enters the outdoor processing unit heat exchanger 3 (the condenser at this time) through the action of the four-way reversing valve 2 to condense. In the heat exchanger 3 of the outdoor processing unit, the refrigerant gas enters the outdoor multi-branch heat exchanger 32 to exchange heat with the air after passing through the outdoor superheater 31 located at the place with the worst heat exchange effect. Under the action of the strong air flow field of the outdoor fan 35 , the refrigerant exchanges heat with the air, and the temperature decreases; among them, the refrigerant in the heat exchange coil branch 321 with the worst heat exchange effect enters the high-pressure liquid storage tank 34, and then merges with the other branches, and passes through the common heat exchange effect The outdoor subcooler 33 at the best place performs subcooling and heat exchange. Thereafter, the refrigerant with a large degree of subcooling passes through the two-way expansion valve 4 to throttle. The throttled and cooled refrigerant enters the heat exchanger 5 (the evaporator at this time) of the indoor air supply unit to exchange heat. In the heat exchanger 5 of the indoor air supply unit, the refrigerant liquid enters the indoor multi-branch heat exchanger 52 to exchange heat with the air through the indoor subcooler 51 located at the best heat exchange effect; The superheater 53 at the bottom is subjected to superheating treatment to obtain a certain degree of superheat, and the refrigerant after superheating is returned to the compressor 1 through the four-way reversing valve 2 . Under the heating condition, the refrigerant becomes a high-temperature and high-pressure gas after passing through the compressor 1, and enters the indoor air supply unit heat exchanger 5 (condenser at this time) for heat exchange through the action of the four-way reversing valve 2. In the heat exchanger 5 of the indoor air supply unit, the refrigerant gas enters the indoor multi-branch heat exchanger 52 through the indoor superheater 53 located at the place with the worst heat exchange effect to exchange heat with the air, and then passes through the common place located at the place with the worst heat exchange effect. The optimal indoor subcooler 51 performs subcooling and heat exchange. Afterwards, the refrigerant with a large subcooling degree passes through the two-way expansion valve 4 to throttle, and enters the outdoor processing unit heat exchanger 3 (the evaporator at this time) for heat exchange. In the heat exchanger 3 of the outdoor processing unit, the refrigerant liquid passes through the outdoor subcooler 33 located at the best heat exchange effect and is divided into two paths after heat exchange. heat exchange in the outdoor multi-branch heat exchanger 321, and the other branch directly enters the outdoor multi-branch heat exchanger 32 to exchange heat with the air, and then passes through the common superheater 31 located at the worst heat exchange effect. Overheating treatment to obtain a certain degree of superheating, and the refrigerant after superheating is returned to the compressor 1 through the four-way reversing valve 2 .

The second embodiment of the present invention is the second type of outdoor processing unit heat exchanger 3 and indoor air supply unit heat exchanger 5 . Both the fans of the heat exchanger 3 of the outdoor processing unit and the heat exchanger 5 of the indoor air supply unit are downward air outlets, and the distribution vector diagrams of their wind speeds conform to the lower triangle. When the structure of the heat exchanger is determined, this specific air supply mode has a one-to-one correspondence with the lower triangular distribution vector diagram of the wind speed. It can be seen from the lower triangular wind speed distribution vector diagram that the wind speed at the lower part of the heat exchanger is high, so when the external air sweeps across the lower branch of the heat exchanger, the effect of forced heat exchange with the refrigerant in the tube is good. The lowermost branch of the heat exchanger 5 of the heat exchanger 3 and the indoor air supply unit is set as an outdoor subcooler 33 and an indoor subcooler 51; When the heat exchange effect is poor with the refrigerant in the tube, the present invention respectively sets the uppermost branch of the indoor air supply unit heat exchanger 5 and the outdoor processing unit heat exchanger 3 as the indoor superheater 53 and the outdoor superheater 31, and the outdoor superheater 31. A branch of the multi-branch heat exchanger 32 adjacent to the outdoor superheater 31 is the branch 321 with the worst heat exchange effect. In the cooling condition, the refrigerant becomes a high-temperature and high-pressure gas after passing through the compressor 1, and enters the outdoor processing unit heat exchanger 3 (the condenser at this time) through the action of the four-way reversing valve 2 to condense. In the heat exchanger 3 of the outdoor processing unit, the refrigerant gas enters the outdoor multi-branch heat exchanger 32 to exchange heat with the air after passing through the outdoor superheater 31 located at the place with the worst heat exchange effect. Under the action of the strong air flow field of the outdoor fan 35 , the refrigerant exchanges heat with the air, and the temperature decreases; among them, the refrigerant in the heat exchange coil branch 321 with the worst heat exchange effect enters the high-pressure liquid storage tank 34, and then merges with the other branches, and passes through the common heat exchange effect The outdoor subcooler 33 at the best place performs subcooling and heat exchange. Thereafter, the refrigerant with a large degree of subcooling passes through the two-way expansion valve 4 to throttle. The throttled and cooled refrigerant enters the heat exchanger 5 (the evaporator at this time) of the indoor air supply unit to exchange heat. In the heat exchanger 5 of the indoor air supply unit, the refrigerant liquid enters the indoor multi-branch heat exchanger 52 to exchange heat with the air through the indoor subcooler 51 located at the best heat exchange effect; The superheater 53 at the bottom is subjected to superheating treatment to obtain a certain degree of superheat, and the refrigerant after superheating is returned to the compressor 1 through the four-way reversing valve 2 . Under the heating condition, the refrigerant becomes a high-temperature and high-pressure gas after passing through the compressor 1, and enters the indoor air supply unit heat exchanger 5 (condenser at this time) for heat exchange through the action of the four-way reversing valve 2. In the heat exchanger 5 of the indoor air supply unit, the refrigerant gas enters the indoor multi-branch heat exchanger 52 through the indoor superheater 53 located at the place with the worst heat exchange effect to exchange heat with the air, and then passes through the common place located at the place with the worst heat exchange effect. The optimal indoor subcooler 51 performs subcooling and heat exchange. Afterwards, the refrigerant with a large subcooling degree passes through the two-way expansion valve 4 to throttle, and enters the outdoor processing unit heat exchanger 3 (the evaporator at this time) for heat exchange. In the heat exchanger 3 of the outdoor processing unit, the refrigerant liquid passes through the outdoor subcooler 33 located at the best heat exchange effect and is divided into two paths after heat exchange. heat exchange in the outdoor multi-branch heat exchanger 321, and the other branch directly enters the outdoor multi-branch heat exchanger 32 to exchange heat with the air, and then passes through the common superheater 31 located at the worst heat exchange effect. Overheating treatment to obtain a certain degree of superheating, and the refrigerant after superheating is returned to the compressor 1 through the four-way reversing valve 2 .

The third embodiment of the present invention is the third type of outdoor processing unit heat exchanger 3 and indoor air supply unit heat exchanger 5 . Both the fans of the heat exchanger 3 of the outdoor processing unit and the heat exchanger 5 of the indoor air supply unit are flat air outlets, and the distribution vector diagrams of their wind speeds conform to an equilateral triangle. When the structure of the heat exchanger is determined, there is a one-to-one correspondence between the specific air supply mode and the equilateral triangle distribution vector diagram of the wind speed. It can be seen from the equilateral triangle wind speed distribution vector diagram that the wind speed in the middle of the heat exchanger is high, so when the external air sweeps across the middle branch of the heat exchanger, the effect of forced heat exchange with the refrigerant in the tube is good, so the present invention uses the outdoor processing unit heat exchanger 3 and the middlemost branch of the heat exchanger 5 of the indoor air supply unit are respectively set as an outdoor subcooler 33 and an indoor subcooler 51; Or the heat exchange effect with the refrigerant in the tube is poor in the lower branch, then there are three options for the setting of the superheater, which are the uppermost branch, the lowermost branch or the uppermost and the lowermost two. Each branch is used as a superheater at the same time. In this embodiment, the uppermost branch of the outdoor processing unit heat exchanger 3 and the indoor air supply unit heat exchanger 5 is selected as the outdoor superheater 31 and the indoor superheater 53, so the outdoor treatment The lowest branch in the unit heat exchanger 3 is the worst effect branch 321 . In the cooling condition, the refrigerant becomes a high-temperature and high-pressure gas after passing through the compressor 1, and enters the outdoor processing unit heat exchanger 3 (the condenser at this time) through the action of the four-way reversing valve 2 to condense. In the heat exchanger 3 of the outdoor processing unit, the refrigerant gas enters the outdoor multi-branch heat exchanger 32 to exchange heat with the air after passing through the outdoor superheater 31 located at the place with the worst heat exchange effect. Under the action of the strong air flow field of the outdoor fan 35 , the refrigerant exchanges heat with the air, and the temperature decreases; among them, the refrigerant in the heat exchange coil branch 321 with the worst heat exchange effect enters the high-pressure liquid storage tank 34, and then merges with the other branches, and passes through the common heat exchange effect The outdoor subcooler 33 at the best place performs subcooling and heat exchange. Thereafter, the refrigerant with a large degree of subcooling passes through the two-way expansion valve 4 to throttle. The throttled and cooled refrigerant enters the heat exchanger 5 (the evaporator at this time) of the indoor air supply unit to exchange heat. In the heat exchanger 5 of the indoor air supply unit, the refrigerant liquid enters the indoor multi-branch heat exchanger 52 to exchange heat with the air through the indoor subcooler 51 located at the best heat exchange effect; The superheater 53 at the bottom is subjected to superheating treatment to obtain a certain degree of superheat, and the refrigerant after superheating is returned to the compressor 1 through the four-way reversing valve 2 . Under the heating condition, the refrigerant becomes a high-temperature and high-pressure gas after passing through the compressor 1, and enters the indoor air supply unit heat exchanger 5 (condenser at this time) for heat exchange through the action of the four-way reversing valve 2. In the heat exchanger 5 of the indoor air supply unit, the refrigerant gas enters the indoor multi-branch heat exchanger 52 through the indoor superheater 53 located at the place with the worst heat exchange effect to exchange heat with the air, and then passes through the common place located at the place with the worst heat exchange effect. The optimal indoor subcooler 51 performs subcooling and heat exchange. Afterwards, the refrigerant with a large subcooling degree passes through the two-way expansion valve 4 to throttle, and enters the outdoor processing unit heat exchanger 3 (the evaporator at this time) for heat exchange. In the heat exchanger 3 of the outdoor processing unit, the refrigerant liquid passes through the outdoor subcooler 33 located at the best heat exchange effect and is divided into two paths after heat exchange. heat exchange in the outdoor multi-branch heat exchanger 321, and the other directly enters the remaining branches of the outdoor multi-branch heat exchanger 32 to exchange heat with the air, and then go through the common superheater 31 located at the worst heat exchange effect. Overheating treatment to obtain a certain degree of superheating, and the refrigerant after superheating is returned to the compressor 1 through the four-way reversing valve 2 .

When the device of the present invention is in operation, the subcooler located at the branch path with the best heat exchange effect with the air in the heat exchanger assembly greatly improves the heat exchange effect of the heat exchanger assembly under the strong wind field of the fan , to ensure the subcooling of the refrigerant. In the heating process, the large subcooling degree can ensure that there are no air bubbles in the refrigerant passing through the two-way expansion valve 4, enhance the stability and reliability of the work of the two-way expansion valve 4, and improve the heat exchange effect of the indoor air supply heat exchanger 5 , increasing the heating capacity. In the cooling process, not only the heat exchange effect of the heat exchanger 3 of the outdoor processing unit is improved, the cooling capacity of the unit is increased, and the energy efficiency ratio (EER) of the cooling unit is improved, but also the area of the outdoor subcooler 33 can be reduced, reducing the equipment cost. The initial investment, but also to ensure the performance of the two-way expansion valve 4. The superheater located at the branch with the worst heat exchange effect with the air in the heat exchanger assembly effectively controls the superheat of the refrigerant to ensure that the superheat of the refrigerant at the inlet of compressor 1 is between 5°C and 11°C, avoiding compression Machine 1 performs wet compression, which effectively improves the performance of the unit and also ensures its stability and safety. In addition, especially during the refrigeration process, after the refrigerant in the branch 321 with the worst heat exchange effect in the outdoor multi-branch heat exchanger enters the high-pressure liquid storage tank 34, it is then mixed with the refrigerant in the other branches. Together, they pass through the outdoor subcooler 33 with the best air heat exchange effect for subcooling and heat exchange, which avoids the inhibition of the subcooling degree of the refrigeration cycle due to the gas-liquid two-phase action of the high-pressure liquid storage tank 34, and effectively improves The heat exchange effect of the heat exchanger 3 of the outdoor processing unit improves the subcooling degree of the refrigerant. All refrigerant equipment of the present invention is connected through refrigerant pipelines, and the refrigerant working medium adopts R22, R134a or R410A and the like.

In addition to being applicable to direct evaporative fresh air air handling units, the present invention can be widely used in other heat pump air-cooled cold (hot) air vapor compression refrigeration cycles to meet the needs of users for stable, high-efficiency, and energy-saving refrigeration (heat). It is expected to produce huge social benefits.

Claims (2)

1. the synchronous brand new air processing group that cold-peace is overheated excessively, it is characterized in that, this unit comprises compressor (1), four-way change-over valve (2), outdoor processing unit heat exchanger (3), Bidirectional expansion valve (4) and indoor blowing unit heat exchanger (5), two interfaces that the inlet end of described compressor (1) is above relative with four-way change-over valve (2) respectively with exhaust end are connected, the refrigeration import of described outdoor processing unit heat exchanger (3) and the refrigeration outlet of indoor blowing unit heat exchanger (5) respectively two other relative interface upper with four-way change-over valve (2) are connected, the refrigeration outlet of outdoor processing unit heat exchanger (3) is connected by the refrigeration import of described Bidirectional expansion valve (4) with indoor blowing unit heat exchanger (5),

Described outdoor processing unit heat exchanger (3) comprises outdoor superheater (31), outdoor multiple branch circuit heat exchanger (32), high pressure fluid reservoir (34), outdoor subcooler (33) and outdoor fan (35), described outdoor superheater (31) and outdoor subcooler (33) are separately positioned on poor with the most best position of heat transfer effect in outdoor processing unit heat exchanger (3) and parallel with outdoor multiple branch circuit heat exchanger (32), the refrigeration outlet of outdoor superheater (31) is connected with the refrigeration import of outdoor multiple branch circuit heat exchanger (32), in outdoor multiple branch circuit heat exchanger (32), the refrigeration outlet of the heat exchange coil (321) of the poorest branch road of heat transfer effect is connected with the refrigeration import of high pressure fluid reservoir (34), the refrigeration outlet of high pressure fluid reservoir (34) is connected with the refrigeration import of outdoor subcooler (33) after being connected by pipeline with the refrigeration outlet of the heat exchange coil of other branch roads in outdoor multiple branch circuit heat exchanger (32) more jointly, the refrigeration import of outdoor superheater (31) is the refrigeration import of outdoor processing unit heat exchanger (3), the refrigeration outlet of outdoor subcooler (33) is the refrigeration outlet of outdoor processing unit heat exchanger (3).

2. the synchronous brand new air processing group that cold-peace is overheated excessively according to claim 1, it is characterized in that, described indoor blowing unit heat exchanger (5) comprises indoor subcooler (51), indoor multiple branch circuit heat exchanger (52), indoor overheating device (53) and indoor fan (54), it is best parallel with indoor multiple branch circuit heat exchanger (52) with the poorest position that indoor subcooler (51) and indoor overheating device (53) are separately positioned on heat transfer effect in indoor blowing unit heat exchanger (5), the refrigeration outlet of indoor subcooler (51) is connected with the refrigeration import of indoor multiple branch circuit heat exchanger (52), the refrigeration outlet of indoor multiple branch circuit heat exchanger (52) is connected with the refrigeration import of indoor overheating device (53), the refrigeration import of indoor subcooler (51) is the refrigeration import of indoor blowing unit heat exchanger (5), the refrigeration outlet of indoor overheating device (53) is the refrigeration outlet of indoor blowing unit heat exchanger (5).