CN201503095U - A Ground Source Directly Coupled Heat Pump Multi-connection Unit - Google Patents

Abstract

The utility model provides a ground source direct coupling type heat pump multi-connection unit, which can be used for central air conditioning systems for indoor air conditioning of small and medium-sized buildings, including compressors, underground vertical U-shaped heat exchange copper tubes, and electronic equipment located indoors and outdoors respectively. The expansion valve is equipped with an indoor heat exchange copper tube of a fan and a four-way reversing valve; wherein the compressor is connected to the underground U-shaped heat-exchanging copper tube through a pipeline through the four-way reversing valve, and the underground U-shaped heat-exchanging copper tube is then The outdoor electronic expansion valve and one-way valve connected in parallel, and the indoor electronic expansion valve are connected to the indoor heat exchange copper pipe provided with the fan in turn, and the indoor heat exchange copper pipe is connected to the compressor to form a circuit. The utility model not only solves the problem that the heat exchange effect of the outdoor heat exchanger fluctuates due to the change of atmospheric meteorological parameters, but also solves the problem that the heat exchange efficiency is relatively low when the traditional water medium is used as the heat exchange carrier. Moreover, the unit has no danger of freezing, has the characteristics of efficient and stable heat exchange, flexible unit installation and strong applicability, so the system has broad development prospects.

Description

A Ground Source Directly Coupled Heat Pump Multi-connection Unit

technical field

The utility model relates to a ground-source direct coupling type heat pump multi-connection unit for small and medium-sized buildings.

Background technique

When the traditional heat pump split unit cools in summer, the condenser directly exchanges heat with the outside air. As the outdoor air temperature rises, the COP of the system will be significantly reduced; while in winter, the four-way reversing valve After conversion, the heat exchanger on the outdoor side is an evaporator, which will require intermittent defrosting as the outdoor temperature drops, and its COP will also be greatly reduced. Compared with the air source, the ground source is a relatively stable temperature field, which attenuates and delays the fluctuation of the surface air temperature. The annual temperature is much lower than the outdoor air temperature in summer and higher than the outdoor air temperature in winter. Therefore, The effect of taking away condensation heat in summer cooling or absorbing heat in winter heating is better than that of air source. Therefore, a lower condensation temperature and a higher evaporation temperature can be provided, thereby increasing the cooling capacity in summer or the heat supply in winter under the same power consumption conditions.

The traditional central air-conditioning system uses water as the heat exchange carrier to transport heat, which is a secondary heat exchange process, and there is heat exchange loss, and its heat exchange efficiency is much lower than that of refrigerant directly exchanging heat with indoor air source or ground source s efficiency.

In addition, the multi-split unit is a hot spot where one outdoor unit is matched with multiple indoor units and has flexible installation. However, the outdoor unit is still air-cooled in essence, and its performance coefficient is also easily changed by the disturbance of the outdoor air.

Utility model content

Aiming at the defects of existing technologies such as the above-mentioned traditional heat pump split unit, traditional central air-conditioning system and multi-connection unit, the purpose of this utility model is to provide a ground source direct coupling type heat pump multi-connection unit, on the one hand to solve the problem of outdoor exchange The heat exchange effect of the heat exchanger is easily fluctuated by changes in atmospheric meteorological parameters. On the other hand, it solves the problem that the traditional water medium is used as the heat exchange carrier to reduce the heat exchange efficiency of the system; the refrigerant directly passes through the indoor heat exchanger and The underground heat exchanger exchanges heat with the indoor air source and the ground source respectively. Due to the direct expansion heat exchange for the refrigerant, the stability and effectiveness of heat exchange are improved, and the traditional water loop is also omitted, and the heat exchange efficiency is greatly improved.

In order to realize the purpose, the technical scheme that the utility model takes is:

A ground-source direct-coupled heat pump multi-unit unit, including a compressor, underground U-shaped heat-exchanging copper pipes, electronic expansion valves located indoors and outdoors, indoor heat-exchanging copper pipes equipped with fans, and a four-way reversing valve; Wherein the compressor is connected to the underground U-shaped heat-exchanging copper pipe through the pipeline through the four-way reversing valve, and the underground U-shaped heat-exchanging copper pipe is then sequentially connected in parallel through the outdoor electronic expansion valve (full open) and the one-way valve, and The electronic expansion valve located indoors is connected to the indoor heat exchange copper tube provided with the fan, and the indoor heat exchange copper tube is connected to the compressor to form a circulation loop.

In order to solve the problem of oil return, an oil separator is installed between the compressor and the four-way reversing valve;

In order to store excess refrigerant to stabilize the refrigerant flow, a liquid receiver is installed between the outdoor electronic expansion valve and the indoor electronic expansion valve; at the same time, a filter is installed between the liquid storage and the indoor electronic expansion valve .

In order to protect the compressor and avoid wet compression, a gas-liquid separator is installed between the compressor and the indoor heat exchange copper tube.

For a system with a load capacity less than 5KW, it is not necessary to install an accumulator, but in a system with a load capacity greater than 5KW, it is necessary to install an accumulator to store excess refrigerant and stabilize the refrigerant flow.

Under cooling conditions, the indoor electronic expansion valve regulates and balances the refrigerant flow, and the outdoor electronic expansion valve is fully open. Under heating conditions, the outdoor electronic expansion valve plays the role of throttling, and the indoor electronic expansion valve plays the role of capacity adjustment and balance. In order to ensure the normal operation of the electronic expansion valve, a filter needs to be installed.

When the utility model is in use, the four-way reversing valve realizes the conversion of cooling in summer and heating in winter:

When operating under refrigeration conditions, the refrigerant becomes a high-pressure and high-temperature gas after passing through the compressor, and enters the underground vertical U-shaped heat-exchanging copper tube (condenser), and the refrigerant exchanges heat with the ground source (soil source or water source) through the copper tube. A refrigerant cooled to a low temperature and high pressure state. Under cooling conditions, the outdoor electronic expansion valve is fully open, and the indoor electronic expansion valve adjusts the refrigerant flow into the indoor heat exchange copper tube to realize the ability to adjust the indoor end. After the refrigerant enters the indoor heat exchange copper tube (evaporator), it absorbs the heat of the indoor air and evaporates into a gaseous state, thereby absorbing the indoor heat to perform indoor air conditioning. The liquid-containing gaseous refrigerant passes through the gas-liquid separator and enters the low-pressure end of the compressor to complete a cycle, and so on.

When the heating operation is in operation, after the four-way reversing valve is converted into a heating path by electric control, the refrigerant becomes a high-pressure and high-temperature gas after passing through the compressor, and then enters the indoor heat-exchanging copper tube (condenser), and through the action of the fan, Through the heat transfer through the copper tube, the heat of the refrigerant is released, the temperature of the indoor air rises due to heat absorption, and the refrigerant is cooled to a low-temperature and high-pressure state. The indoor electronic expansion valve regulates and balances the refrigerant flow, and then enters the underground U-shaped buried pipe heat exchange copper pipe (evaporator) after the throttling and pressure reduction of the outdoor electronic expansion valve. The refrigerant absorbs the ground source (water source or soil source) ) evaporates into a gaseous state. The liquid-containing gaseous refrigerant passes through the gas-liquid separator and enters the low-pressure end of the compressor to complete a cycle, and so on.

In summary, compared with the prior art, the utility model has the following advantages:

1. It directly exchanges heat with the soil, eliminating the intermediate heat exchange process of the water loop, reducing heat exchange links, and improving energy utilization. The system efficiency is improved and more energy-saving.

2. The heat exchange belongs to the phase change heat of the refrigerant. Under the same conditions, its heat transfer coefficient is much larger than that of water, air and other heat transfer media.

3. The heat exchanger is directly filled with refrigerant, there is no danger of freezing, and there is no need to add antifreeze. No need for defrosting, more energy efficient than air source heat exchangers.

4. The indoor unit is relatively independent, can be flexibly arranged, and can save daily operating costs. It can combine rooms with different functions and different use times into the same air-conditioning system.

5. Due to the reduction of intermediate heat exchange pipelines, the consumption of pipe materials is relatively reduced, and the amount of underground construction is also relatively reduced.

Description of drawings

Fig. 1 is the schematic diagram of the refrigeration working condition system in the embodiment;

Fig. 2 is the schematic diagram of the heating working condition system in the embodiment;

1——Underground U-shaped copper tube heat exchanger 2——Compressor 3——Gas-liquid separator

4——Oil separator 5——Four-way reversing valve 10——Reservoir

11——Electronic expansion valve located outside 12——One-way valve

6-1, 6-2, 6-N——Indoor electronic expansion valve 7-1, 7-2, 7-N——Indoor heat exchange copper pipe

8-1, 8-2, 8-N——fan 9-1, 9-2, 9-N——filter

9-1', 9-2', 9-N' - filter

Detailed ways:

As shown in Figures 1 and 2, this embodiment provides a ground-source direct-coupled heat pump multi-unit unit, including a compressor 2, an underground U-shaped heat exchange copper tube 1, an indoor electronic expansion valve, and an outdoor electronic expansion valve. Valve 11, the indoor heat exchange copper pipe 7 provided with the fan 8 and the four-way reversing valve 5; wherein the compressor 2 is connected to the underground U-shaped heat exchange copper pipe 1 through a pipeline through the four-way reversing valve 5, and the underground U-shaped Type heat exchange copper pipe 1 is connected to indoor heat exchange copper pipe 7 provided with fan 8 through parallel connected outdoor electronic expansion valve (full open) 11 and check valve 12, and indoor electronic expansion valve 6 , the indoor heat exchange copper tube 7 is then connected to the compressor 2 to form a circuit. The refrigerant (eg R22, R134) directly exchanges energy with the indoor heat exchange copper tube 7 in the underground U-shaped copper tube heat exchanger 1 . Since the refrigerant pipeline directly exchanges heat underground, the underground buried pipe cannot use plastic pipes due to pressure and leakage, but copper pipes. Underground copper tube heat exchanger 1 adopts vertical U-shaped heat exchange copper tubes (the condensation side is used for cooling in summer, and the evaporation side is used for heating in winter). The depth of buried pipes is between 20 meters and 80 meters below the ground. Determined by the load on the system. The refrigerant exchanges energy with the indoor air in the indoor heat exchange copper pipe 7 through the reinforcement of the fan 8. The diameter of the copper pipe is DN10-DN16, and the number of rows is determined according to the heat exchange. In summer, the cooling acts as the evaporation side to absorb the heat in the room, and in the winter heating, it acts as the condensation side to release heat, so as to achieve the purpose of regulating the indoor air. The indoor electronic expansion valve 6 can adjust the change of refrigerant flow rate according to the change of user side load. The refrigerant directly exchanges heat with the terminals in both the underground U-shaped heat exchange copper pipe 1 and the indoor heat exchange copper pipe 7 , which saves the intermediate heat exchange process and improves the efficiency. Among them, the above-mentioned compressor 2, the underground U-shaped heat exchange copper pipe 1, the electronic expansion valve located indoors, the outdoor electronic expansion valve 11, the indoor heat exchange copper pipe 7 provided with the fan 8 and the four-way reversing valve 5 can all be used Existing devices in the prior art.

Referring to the accompanying drawing 1, when the refrigeration operation is in operation, the refrigerant (such as: R22) is compressed by the compressor 2 to become a high-temperature and high-pressure gas, and first passes through the oil separator 4 to realize the purpose of oil return in the system. After the refrigerant enters the underground U-shaped heat exchange copper tube 1 through the reversing four-way reversing valve 5, the refrigerant directly exchanges heat with the ground source in the U-shaped heat exchange copper tube 1 to become a low-temperature and high-pressure state, and flows through the outdoor electronic system. Expansion valve 11 (fully open) and check valve 12 then flow into the accumulator. The liquid receiver can store a part of excess refrigerant to stabilize the refrigerant flow. Before the refrigerant enters the indoor electronic expansion valve, it needs to pass through the filter 9 to protect the electronic expansion valve. The low-temperature and high-pressure refrigerant becomes a low-temperature and low-pressure state after the throttling and flow regulation of the electronic expansion valve 6 in each room realizes the on-demand distribution of refrigerant flow and throttling and pressure reduction. At this time, the refrigerant (such as: R22 ) to evaporate in the indoor heat exchange copper tube 7 needs to absorb a large amount of heat from the room, coupled with the heat transfer enhancement effect of the fan 8, to realize the physical process of the refrigerant absorbing the heat in the room, and to make itself a low-temperature and low-pressure liquid refrigerant. The gas-liquid separator 3 prevents the compressor 2 from wet compression. Complete a refrigeration cycle, so as to achieve the purpose of cooling in summer.

Referring to Figure 2, when the heating operation is in operation, the four-way reversing valve 5 is switched first, and the refrigerant (such as: R22) is compressed by the compressor 2 to become a high-temperature and high-pressure gas, which is passed into the oil separator 4 to realize oil return. After the purpose, the refrigerant (such as: R22) directly enters the indoor heat exchange copper pipe 7 to condense and release heat under the strengthening effect of the fan 8, bringing a large amount of heat to the room to achieve the purpose of heating. Refrigerant (such as R22) becomes a low temperature and high pressure state after condensing and exothermic heat. Refrigerant enters the liquid storage after being adjusted and balanced by the indoor electronic expansion valve 6, and then enters the underground U-shaped heat exchange copper tube after being throttled and depressurized by the outdoor electronic expansion valve 11, directly from the ground source Absorb heat and evaporate into gaseous refrigerant. In order to avoid the wet compression of the compressor 2 as much as possible, the gas-liquid separation of the gas-liquid separator 3 before entering the low-pressure end of the compressor protects the normal operation of the compressor. So far, a cycle of heating is completed, and the purpose of heating in winter is reached again and again.

In order to ensure the normal and stable operation of the system, auxiliary devices are required. The oil separator 4 is installed to solve the oil return problem, and the liquid receiver 10 is installed to store excess refrigerant to stabilize the refrigerant flow; in order to protect the compressor and avoid wet compression, the refrigerant needs to pass through the gas-liquid separator 3 before entering the compressor 2 protection of. The refrigerant needs to be protected by the filter 9 before entering the electronic expansion valves 6 and 11.

Claims (7)

1. a ground source direct coupled type heat pump multi-joint unit is characterized in that comprising compressor, and underground vertical U type heat exchange copper tube lays respectively at the electric expansion valve of indoor and outdoors, is provided with the indoor heat exchange copper tube and the four-way change-over valve of blower fan; Wherein compressor is connected with underground U type heat exchange copper tube by pipeline through four-way change-over valve, described underground U type heat exchange copper tube is more successively through outdoor electric expansion valve and the check valve that connects arranged side by side, and be positioned at indoor electric expansion valve and insert the indoor heat exchange copper tube that is provided with blower fan, described indoor heat exchange copper tube inserts compressor at last, constitutes closed circuit.

2. according to the multi-joint unit of source, described ground of claim 1 direct coupled type heat pump, it is characterized in that being provided with oil eliminator between described compressor and the four-way change-over valve.

3. according to the multi-joint unit of source, described ground of claim 1 direct coupled type heat pump, it is characterized in that being provided with reservoir at outdoor electric expansion valve with between indoor electric expansion valve.

4. according to the multi-joint unit of source, described ground of claim 3 direct coupled type heat pump, it is characterized in that between reservoir and indoor electric expansion valve, being provided with filter.

5. according to the multi-joint unit of source, described ground of claim 1 direct coupled type heat pump, it is characterized in that being provided with gas-liquid separator between compressor and the indoor heat exchange copper tube.

6. according to the multi-joint unit of source, described ground of claim 1 direct coupled type heat pump, it is characterized in that described underground U type heat exchange copper tube adopts the perpendicularly buried pipe form to install, pipe laying depth is 20 meters-80 meters of below grounds.

7. according to the multi-joint unit of source, described ground of claim 1 direct coupled type heat pump, the diameter that it is characterized in that indoor heat exchange copper tube is DN10-DN16.

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