CN111678270A - A heat pipe and vapor compression composite system with a self-operated capacity-regulating accumulator - Google Patents

Abstract

The invention discloses a heat pipe and vapor compression composite system with a self-operated capacity adjustment liquid accumulator, comprising an evaporator, a compressor, a condenser, a throttling device, a first bypass valve connected in parallel with the compressor, and a throttling device. The second bypass valve is connected in parallel, and a self-operated capacity-adjusting liquid accumulator is installed on the condenser outlet pipeline; the self-operating capacity-adjusting liquid accumulator includes a liquid storage chamber, a piston, a regulating chamber, a spring, an inlet pipe end, and an outlet pipe end , Front limit pin and rear limit pin, the inlet and outlet ports are respectively set up and down the liquid storage chamber, the liquid storage chamber and the adjustment chamber are isolated by the piston, the piston is connected with the spring, the front limit pin and the rear limit pin limit Piston movement position. The self-operated capacity-adjusting liquid accumulator of the present invention can ensure that both the heat pipe mode and the vapor compression mode work under their respective optimal refrigerant charge, and ensure that both the heat pipe mode and the vapor compression mode operate efficiently.

Description

A heat pipe and vapor compression composite system with a self-operated capacity-regulating accumulator

Technical field:

The invention relates to a heat pipe and vapor compression composite system with a self-operated capacity-adjusting liquid accumulator, which is suitable for heat dissipation of data centers, communication base stations and electronic equipment, and belongs to the field of equipment thermal management and environmental control.

Background technique:

Heat pipe and vapor compression composite refrigeration technology is a refrigeration technology that integrates the two cycle modes of heat pipe cycle and vapor compression cycle. : 200810118209.2), solar air source heat pump system (a solar air source heat pump, application number: 201511029273.X), high-energy weapon heat dissipation and other fields (a modular composite high-energy weapon heat dissipation system and its control method, application number: 201710252599.1 ). This technology usually includes an evaporator, a condenser, a compressor, a throttling device, a first bypass branch arranged in parallel with the compressor, and a second bypass branch arranged in parallel with the throttling device. When the outdoor temperature is low or the heat dissipation is low, the compressor and the throttling device stop working, the first bypass branch and the second bypass branch are opened, and the system operates in the heat pipe circulation mode. In fact, lower energy consumption can be achieved. Energy saving; when the outdoor temperature is low or the heat dissipation is high, the compressor and the throttling device are operated, the first bypass branch and the second bypass branch are closed, and the system operates in the vapor compression mode to ensure the safe operation of the system. At the same time, the system has the advantages of compact structure, easy control, energy saving, material saving, land saving and initial investment saving, and has a good application prospect.

Then, in the application process, it is found that the composite refrigeration technology is difficult to operate efficiently in both the heat pipe mode and the vapor compression mode. One of the main reasons is the mismatch of refrigerant charge. A composite refrigeration system shares the evaporator and condenser, and the refrigerant charge is also fixed. However, generally, the refrigerant charge required by the heat pipe mode is large, and the charge required by the vapor compression mode is small, so it is difficult to ensure that both working modes are at the optimal charge. When the charging amount is large, the vapor compression mode will have liquid accumulation, resulting in poor performance; when the charging amount is small, the heat pipe circulation mode cannot form a driving liquid column, and the evaporator will overheat, resulting in poor performance. Adding a traditional fixed volume accumulator will not solve this problem, because a large amount of refrigerant will still stay in the accumulator in heat pipe mode and cannot participate in the circulation, and the fixed volume accumulator usually reduces the heat pipe circulation driving fluid. column.

Invention content:

In view of the deficiencies of the prior art, the present invention proposes a heat pipe and vapor compression composite system with a self-operated capacity-regulating liquid accumulator. All refrigerants participate in the heat pipe cycle; in the vapor compression mode, the volume of the liquid storage chamber of the accumulator becomes larger, the excess refrigerant is stored in the liquid accumulator, and only a small amount of refrigerant participates in the vapor compression cycle. In the heat pipe mode and the vapor compression mode, the system can work with their respective optimal charging amounts to ensure the efficient operation of the two working modes of the composite system. In addition, the volume adjustment of the accumulator is self-driven by the pressure difference established by the compressor, no additional power is required, the control is simple and the reliability is high.

The technical scheme adopted in the present invention is as follows: a heat pipe and vapor compression composite system with a self-operated capacity adjustment liquid accumulator, comprising an evaporator, a compressor, a condenser, a throttling device, and a first bypass connected in parallel with the compressor a valve, a second bypass valve connected in parallel with the throttling device, and a self-operated capacity-adjusting liquid accumulator is arranged on the outlet pipeline of the condenser;

The self-operated capacity adjustment liquid accumulator includes a liquid storage cavity, a piston, an adjustment cavity, a spring, an inlet pipe end, an outlet pipe end, a front limit pin and a rear limit pin, and the upper and lower parts of the liquid storage cavity are respectively provided with the inlet pipe ends and the outlet pipe end, the liquid storage chamber and the adjustment chamber are isolated by a piston, the piston is connected with a spring, and the front limit pin and the rear limit pin limit the movement position of the piston.

Further, the liquid storage chamber is connected between the outlet of the condenser and the inlet of the throttling device through the inlet pipe end and the outlet pipe end.

Further, a low-pressure connecting pipe is also included, and the regulating chamber is connected with the outlet pipeline of the throttling device through the low-pressure connecting pipe.

Further, the self-operated capacity adjustment liquid reservoir adopts external heat preservation measures.

Further, the heat pipe with the self-operated capacity-adjusting liquid accumulator and each structure in the vapor compression composite system are sequentially connected through a refrigerant pipeline to form a closed system, and the refrigerant pipeline is filled with refrigerant.

Further, the elastic force of the spring is greater than the friction force for pushing the piston, and smaller than the thrust force formed by the difference between the condensation pressure and the evaporation pressure.

The present invention has the following beneficial effects:

(1) The accumulator with self-operated capacity adjustment can ensure that both the heat pipe mode and the vapor compression mode work under their respective optimal refrigerant charge, ensuring that both the heat pipe mode and the vapor compression mode operate efficiently;

(2) The system uses the power of the compressor to independently change the capacity of the accumulator without external power, with simple control and stable and reliable work;

(3) While using the accumulator, the composite system retains the self-regulating performance that the heat pipe can automatically adjust the flow rate according to the size of the heat load.

Description of drawings:

FIG. 1 is a schematic structural diagram of the heat pipe and vapor compression composite system with a self-operated capacity-regulating liquid accumulator according to the present invention.

FIG. 2 is a flow chart of the heat pipe of the heat pipe and vapor compression composite system with a self-operated capacity-regulating accumulator according to the present invention.

FIG. 3 is a flow chart of the vapor compression of the heat pipe and vapor compression composite system with a self-operated capacity-regulating accumulator according to the present invention.

in:

1-Self-operated capacity adjustment liquid accumulator; 2-Evaporator; 3-Compressor; 4-Condenser; 5-Throttle device; 6-First bypass valve; 7-Second bypass valve; 8-Low pressure Connecting pipe; 11-liquid storage chamber; 12-piston; 13-adjustment chamber; 14-spring; 15-inlet pipe end; 16-outlet pipe end; 17-front limit pin; 18-rear limit pin.

Detailed ways:

The present invention will be further described below in conjunction with the accompanying drawings.

As shown in FIG. 1 , the heat pipe and vapor compression composite system with self-operated capacity adjustment liquid accumulator of the present invention includes an evaporator 2 , a compressor 3 , a condenser 4 , a throttling device 5 , and a first parallel connection with the compressor 3 . The bypass valve 6 and the second bypass valve 7 connected in parallel with the throttling device 5 are provided on the outlet pipeline of the condenser 4 with a self-operated capacity adjustment accumulator 1 . The self-operated capacity adjustment accumulator 1 includes a liquid storage chamber 11, a piston 12, an adjustment chamber 13, a spring 14, an inlet nozzle end 15, an outlet nozzle end 16, a front limit pin 1 and a rear limit pin 18; the liquid storage chamber 11 The inlet pipe end 15 and the outlet pipe end 16 are connected between the outlet of the condenser 4 and the inlet of the throttle device 5, the liquid storage chamber 11 and the adjustment chamber 13 are isolated by the piston 12, the piston 12 is connected with the spring 14, and the front limit pin 17 and the rear limit pin 18 limit the moving position of the piston 12 , and the regulating chamber 13 is connected with the outlet pipe of the throttle device 5 through the low pressure connecting pipe 8 . The pressure of the liquid storage chamber is the outlet pressure of the condenser, and the pressure of the regulating chamber is the outlet pressure of the throttling device. The entire self-operated capacity-regulating reservoir 1 adopts external heat preservation measures. In different operating modes of the system, the piston 12 is automatically driven according to the pressure difference established by the compressor, and then the volume of the liquid storage chamber 11 is changed.

Among them, the heat pipe with self-operated capacity-adjusting liquid accumulator and each equipment in the vapor compression composite system are sequentially connected through a refrigerant pipeline to form a closed system, and the refrigerant pipeline is filled with refrigerant.

The working principle of the heat pipe and vapor compression composite system with self-operated capacity-regulating liquid accumulator of the present invention is as follows:

(a) When the system operates in the heat pipe mode, the compressor 3 and the throttling device 5 are closed, the first bypass valve 6 and the second bypass valve 7 are opened, and the liquid storage chamber 11 of the self-operated capacity adjustment accumulator 1 and the adjustment The internal pressure of the cavity 13 is approximately equal. Under the elastic force of the spring 14, the piston 12 is pushed to the front limit pin 17, the volume of the liquid storage cavity 11 becomes smaller, and most of the refrigerant in the system enters the heat pipe cycle. The accumulator 1 participates in the heat pipe cycle as a section of the down pipe to ensure the efficient operation of the heat pipe cycle, as shown in Figure 2.

(b) When the system operates in vapor compression mode, the first bypass valve 6 and the second bypass valve 7 are closed, the compressor 3 and the throttling device 5 are opened, and the liquid storage chamber of the self-operated capacity adjustment accumulator 1 is at this time. The inside of 11 is the condensing pressure, the regulating chamber 13 of the accumulator is the evaporation pressure, and the pressure difference between the two is relatively large, usually greater than 2bar. Under the action of the pressure difference between the condensation pressure and the evaporation pressure, the spring 14 is squeezed, the piston 12 is pushed to the rear limit pin 18, the volume of the liquid storage chamber 11 of the self-operated capacity adjustment accumulator 1 becomes larger, and the excess refrigerant is removed Stored in the accumulator, only a small amount of refrigerant participates in the vapor compression cycle, ensuring the efficient operation of the vapor compression cycle, as shown in Figure 3.

It should be noted that the elastic force of the spring 14 should be greater than the frictional force pushing the piston 12 and less than the thrust force formed by the difference between the condensation pressure and the evaporation pressure. The volume of the self-operated capacity adjustment accumulator 1, the positions of the front limit pin 17 and the rear limit pin 18, and the initial refrigerant charge should be determined according to the actual situation to ensure that both the heat pipe mode and the vapor compression mode are optimal charge amount. For example, the optimal charging capacity of heat pipe mode is 500g, the charging capacity of vapor compression mode is 300g, and the initial charging capacity can be designed to be 600g. Refrigerant 300g, at least 100g refrigerant. This ensures that in the heat pipe mode, the refrigerant in the liquid storage chamber is about 100g, and the refrigerant in the heat pipe cycle is about 500g; in the vapor compression mode, the refrigerant in the liquid storage chamber is about 300g, and the refrigerant in the vapor compression cycle is about 300g.

In addition, in the combined heat pipe and vapor compression system, the position of the condenser 4 is higher than that of the evaporator 2, and the self-operated capacity-regulating accumulator 1 should be installed at the outlet of the condenser to maintain a certain height difference with the evaporator 2, so as to facilitate the The driving liquid column is formed in the heat pipe mode.

The above are only the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, several improvements can be made without departing from the principles of the present invention, and these improvements should also be regarded as the invention. protected range.

Claims (6)

1. A heat pipe and vapor compression composite system with a self-operated capacity-regulating liquid storage device, characterized in that: comprising an evaporator (2), a compressor (3), a condenser (4), a throttling device (5), A first bypass valve (6) connected in parallel with the compressor (3), a second bypass valve (7) connected in parallel with the throttling device (5), and a self-contained capacity is provided on the outlet pipeline of the condenser (4) Regulating reservoir (1); The self-operated capacity adjustment liquid accumulator (1) comprises a liquid storage chamber (11), a piston (12), an adjustment chamber (13), a spring (14), an inlet pipe end (15), an outlet pipe end (16), The front limit pin (17) and the rear limit pin (18), the liquid storage chamber (11) is respectively provided with an inlet pipe end (15) and an outlet pipe end (16), the liquid storage chamber (11) and the The adjusting chamber (13) is isolated by the piston (12), the piston (12) is connected with the spring (14), and the front limit pin (17) and the rear limit pin (18) limit the movement position of the piston (12). 2. The heat pipe and vapor compression composite system with a self-operated capacity-regulating liquid accumulator according to claim 1, wherein the liquid accumulating cavity (11) passes through the inlet pipe end (15) and the outlet pipe end (16). ) is connected between the outlet of the condenser (4) and the inlet of the throttling device (5). 3. The heat pipe and vapor compression composite system with self-contained capacity regulating liquid accumulator according to claim 1, characterized in that: it also comprises a low pressure connecting pipe (8), and the regulating cavity (13) is connected by a low pressure connecting pipe (8). 8) Connect to the outlet pipeline of the throttle device (5). 4 . The heat pipe and vapor compression composite system with a self-operated capacity-regulating liquid accumulator according to claim 1 , wherein the self-operating capacity-regulating liquid accumulator ( 1 ) adopts external heat preservation measures. 5 . 5. The heat pipe and vapor compression composite system with a self-operated capacity-regulating liquid accumulator according to claim 1, wherein each structure in the heat pipe with a self-operating capacity-regulating liquid accumulator and the vapor compression composite system is one of the They are connected in turn through a refrigerant pipeline to form a closed system, and the refrigerant pipeline is filled with refrigerant. 6. The heat pipe and vapor compression composite system with a self-operated capacity-adjusting liquid accumulator according to claim 1, characterized in that: the elastic force of the spring (14) is greater than the frictional force of the pushing piston (12), and less than the condensation pressure The thrust formed by the difference between the evaporation pressure and the evaporation pressure.

Images