An air source heat pump hot water thermal storage defrosting system based on shell and tube heat exchanger

Abstract

The present invention provides an air source heat pump hot water heat storage defrosting system based on a shell and tube heat exchanger, comprising a heating water circulation module, a heat storage module, a refrigerant circulation module, and a heat exchange module; the refrigerant circulation module is connected to the heat exchange module, the heating water circulation module is connected to the heat exchange module, and the refrigerant circulation module and the heating water circulation module transfer heat through the heat exchange module; the heat exchange module is arranged in the heat storage module, and the heat storage module is used to store heat through the heat exchange module; the heat storage medium in the heat storage module includes water. The beneficial effects of the present invention are as follows: the present invention is designed with a plurality of heating and heat storage operation modes, and the switching between different heating and heat storage modes is simple, and the reasonable distribution of the heating amount of the unit under different operating environments can be realized, thereby ensuring that the heating effect and defrosting effect of the unit can satisfy the user, and greatly improving the indoor comfort during heating.

Description

Technical Field

[0001] The invention belongs to the technical field of air source heat pumps for heating, ventilation and air conditioning, and in particular relates to an air source heat pump hot water heat storage and defrosting system based on a shell-and-tube heat exchanger. Background Art

[0002] Air source heat pump water heaters have been widely used in recent years due to their advantages such as energy saving, high efficiency, safety and reliability. However, when operating in a low temperature and high humidity environment (such as the middle and lower reaches of the Yangtze River in my country), the evaporator of the unit will frost. The frost blocks the air passage, increases the heat transfer resistance on the air side, and causes a significant decrease in the heating capacity of the unit, so the evaporator needs to be defrosted periodically. The existing reverse cycle defrosting technology needs to absorb heat from the hot water on the user side or the indoor heat for defrosting, which will cause a significant drop in indoor temperature, seriously affecting the indoor comfort on the user side, and also reducing the heating efficiency of the unit, so it is necessary to develop new defrosting technology to solve this problem. Summary of the invention

[0003] In view of this, the present invention aims to propose an air source heat pump hot water thermal storage defrosting system based on a shell and tube heat exchanger to solve the defrosting problem of the air source heat pump.

[0004] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0005] An air source heat pump hot water heat storage defrosting system based on a shell and tube heat exchanger, comprising a heating water circulation module, a heat storage module, a refrigerant circulation module, and a heat exchange module;

[0006] The refrigerant circulation module is connected to the heat exchange module, the heating water circulation module is connected to the heat exchange module, and the refrigerant circulation module and the heating water circulation module transfer heat through the heat exchange module;

[0007] The heat exchange module is arranged in the heat storage module, and the heat storage module is used to store heat through the heat exchange module;

[0008] The heat storage medium in the heat storage module includes water.

[0009] Further, the heating water circulation module includes a first water pipe, a second water pipe, a first water valve, a fifth water valve, a three-way valve, and a water pump;

[0010] One end of the first water pipe is connected to the heat exchange module through a three-way valve, and the other end is used to transport heating water to the user;

[0011] The heating return water passes through the second water pipe and the first water valve, and then is pressurized by a water pump and returned to the heat exchange module through the fifth water valve.

[0012] Furthermore, the heat storage module includes a shell, and a partition is arranged in the shell, the partition divides the inner cavity of the shell into an upper cavity and a lower cavity, and the upper cavity and the lower cavity are filled with a heat storage medium;

[0013] The inner wall and the outer wall of the shell are provided with a layer of heat-insulating material;

[0014] A conduction unit is arranged between the upper cavity and the lower cavity, and the heat storage medium is transferred between the upper cavity and the lower cavity through the conduction unit.

[0015] Further, the conduction unit includes a fourth water pipe, a fifth water pipe, a third water valve, and a fourth water valve;

[0016] The fourth water pipe is arranged to penetrate the partition plate, and the upper end opening of the fourth water pipe is communicated with the upper cavity;

[0017] The middle part of the fourth water pipe is connected to the fourth water valve through the fifth water pipe, and the fourth water valve is connected to the lower cavity at one end away from the fifth water pipe;

[0018] The lower end of the fourth water pipe is connected to the water outlet of the water pump through the third water valve;

[0019] The conduction unit also includes a third water pipe and a second water valve. One end of the third water pipe is connected to the interior of the lower cavity, and the other end is connected to the second water pipe located between the first water valve and the water pump. The second water valve is arranged on the pipeline of the third water pipe.

[0020] Further, the heat exchange module includes a shell and tube heat exchanger, the shell and tube heat exchanger includes an inner tube and an outer tube, and an internal hollow portion is provided between the inner tube and the outer tube;

[0021] The outer middle cavity portion of the shell and tube heat exchanger is filled with a heat storage medium;

[0022] The upper part of the shell and tube heat exchanger is the inlet end, and the lower part is the outlet end;

[0023] The inner tube water outlet at the inlet end is connected to the first water pipe through a three-way valve, the inlet end of the three-way valve is connected to the inner tube water outlet, the first water outlet of the three-way valve is connected to the inlet of the first water pipe, and the second water outlet of the three-way valve is connected to the heat storage medium in the lower cavity;

[0024] The heating return water is input to the inner pipe water inlet located at the outlet end through the fifth water valve;

[0025] The refrigerant is input into the heat exchange module through the internal hollow portion inlet located at the inlet end;

[0026] The refrigerant is returned to the refrigerant circulation module through the internal hollow outlet located at the outlet end.

[0027] Furthermore, the refrigerant circulation module includes a compressor, a four-way valve, an air-cooled evaporator, a throttle valve, and a gas-liquid separator;

[0028] The refrigerant transported back through the outlet of the internal hollow part of the heat exchange module is connected to the inlet end of the throttle valve through a pipeline;

[0029] The inlet of the air-cooled evaporator is connected to the outlet of the throttle valve;

[0030] The refrigerant coming out of the outlet of the air-cooled evaporator passes through the four-way valve and the gas-liquid separator and is sucked into the suction port of the compressor;

[0031] The refrigerant output by the compressor is delivered to the heat exchange module through the four-way valve and the inlet of the internal hollow part.

[0032] Compared with the prior art, the air source heat pump hot water heat storage defrosting system based on a shell and tube heat exchanger described in the present invention has the following beneficial effects:

[0033] (1) The technical solution proposed by the present invention is based on the characteristic that the outer part of the shell and tube heat exchanger is hollow. The hollow part is filled with hot water to store the excess heat of the system during normal heating. During defrosting, this part of hot water enters the shell and tube heat exchanger and performs forced convection heat exchange with the refrigerant. Compared with the existing heat storage defrosting technology, the present invention does not need to add an additional heat exchanger, which reduces the space occupied by the unit. In addition, the use of water to store heat greatly reduces the additional cost. At the same time, the heat exchange effect of the heat exchanger during defrosting is improved, which greatly shortens the defrosting time.

[0034] (2) The present invention is designed with a variety of heating and heat storage operation modes. It is easy to switch between different modes, and can achieve reasonable distribution of the unit's heating capacity under different operating environments, ensuring that the unit's heating and defrosting effects can satisfy users, greatly improving indoor comfort during heating.

[0035] (3) During the defrosting process of the system, the shell-and-tube heat exchanger acts as an evaporator. The low-temperature refrigerant in the tube gap can not only perform forced convection heat exchange with the thermal storage hot water flowing in the inner tube, but also perform disturbance heat exchange with the thermal storage hot water (because water continuously flows in and out of the thermal storage hot water, which will cause disturbance to the thermal storage hot water), thereby greatly enhancing the heat exchange effect of the heat exchanger. Compared with the existing hot water, especially the phase change thermal storage defrosting technology (the heat exchange between the refrigerant and the phase change material is mainly the heat conduction of the phase change material), the defrosting time can be greatly shortened. At the same time, it can avoid absorbing heat from the room during the defrosting period, thereby ensuring the indoor comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0037] Figure 1 is a system principle diagram of Embodiment 1 of the present invention;

[0038] Figure 2 This is a schematic diagram of a heating water circulation module and a heat storage module according to the first embodiment of the present invention;

[0039] Figure 3 It is a schematic diagram of a heating water circulation module and a heat storage module according to the second embodiment of the present invention.

[0040] Explanation of the accompanying drawings: 1-compressor; 2-four-way valve; 3-air-cooled evaporator; 4-throttle valve; 5-gas-liquid separator; 6-shell heat exchanger; 61-housing; 62-three-way valve; 7-water pump; 8-first water pipe; 9-second water pipe; 10-third water pipe; 11-first water valve; 12-second water valve; 13-third water valve; 14-fourth water pipe; 15-fourth water valve; 16-fifth water pipe; 17-fifth water valve; 18-partition. DETAILED DESCRIPTION

[0041] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0042] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0043] An air source heat pump hot water heat storage defrosting system based on a shell and tube heat exchanger, the system includes a compressor 1, a four-way valve 2, an air-cooled evaporator 3, a throttle valve 4, and a gas-liquid separator 5, characterized in that the system also includes a shell and tube heat exchanger 6, a shell 61, a three-way valve 62, a water pump 7, a first water pipe 8, a second water pipe 9, a third water pipe 10, a first water valve 11, and a second water valve 12. The shell and tube heat exchanger 6 is composed of an inner tube and an outer tube, the inner tube carries water, and the gap between the inner tube and the outer tube carries refrigerant. The inlet end of the heat exchanger 6 is provided with a hot water inlet end and a refrigerant inlet end, and the outlet end of the heat exchanger 6 is provided with a hot water outlet end and a refrigerant outlet end. The outer middle cavity of the heat exchanger is filled with hot water. The shell 61 only wraps and seals the heat exchanger 6 inside, so that the heat exchanger 6 and the hot water are isolated from the outside. The shell 61 is provided with a heat preservation material. The inlet of the three-way valve 62 is connected with the hot water outlet end, and the first outlet of the three-way valve 62 is connected with the inlet of the first water pipe 8. The three-way valve 6 The second outlet of the first water pipe 2 is connected to the hot water, the outlet of the first water pipe 8 is connected to the heat exchanger in the heating room, the hot water inlet end is connected to the inlet of the second water pipe 9, the outlet of the second water pipe 9 is connected to the heat exchanger in the heating room, the second water pipe 9 is provided with a water pump 7, a first water valve 11 is provided on the pipeline between the water inlet of the water pump 7 and the outlet of the second water pipe 9, the inlet of the third water pipe 10 is connected to the hot water in the housing 61, the outlet of the third water pipe 10 is connected to the water inlet of the water pump 7, the third A second water valve 12 is provided on the water pipe 10, the refrigerant inlet end of the shell and tube heat exchanger 6 is connected to the second port of the four-way valve 2, the first port of the four-way valve 2 is connected to the exhaust port of the compressor 1, the third port of the four-way valve 2 is connected to the inlet of the gas-liquid separator 5, the outlet of the gas-liquid separator 5 is connected to the intake port of the compressor 1, the fourth port of the four-way valve 2 is connected to the outlet of the air-cooled evaporator 3, the inlet of the air-cooled evaporator 3 is connected to the outlet of the throttle valve 4, and the inlet of the throttle valve 4 is connected to the refrigerant outlet end of the shell and tube heat exchanger 6.

[0044] The system further comprises a partition 18, a fourth water pipe 14, a fifth water pipe 16, a third water valve 13, a fourth water valve 15 and a fifth water valve 17. The partition 18 is located at the upper part of the shell and tube heat exchanger 6 and contacts the shell and tube heat exchanger 6. The partition 18 divides the shell 61 into two closed spaces, the upper half of which is filled with hot water, and the lower half of which is filled with hot water and submerges the shell and tube heat exchanger 6. The inlet of the fourth water pipe 14 is connected to the outlet of the water pump 7. The fourth water pipe 14 passes through the partition and its outlet The third water valve 13 is arranged on the fourth water pipe 14, the fifth water pipe 16 is located in the lower half of the outer shell 61, the inlet of the fifth water pipe 16 is connected to the pipeline between the third water valve 13 and the outlet of the fourth water pipe 14, the outlet of the fifth water pipe 16 is connected to the hot water in the lower half of the outer shell 61, the fourth water valve 15 is located on the fifth water pipe 16, and the fifth water valve 17 is located on the pipeline of the second water pipe 9 between the outlet of the water pump 7 and the hot water inlet end of the shell heat exchanger 6.

[0045] The height of the upper half of the housing 61 is approximately 20% of the lower half.

[0046] About 20% of the outer surface of the shell-and-tube heat exchanger 6 is wrapped with insulation material.

[0047] Embodiment 1

[0048] like Figure 1 and Figure 2 As shown, the technical solution of this embodiment is as follows:

[0049] The working principle of this embodiment is as follows:

[0050] When the system operates in heating and heat storage mode, the first water valve 11 is opened, the second water valve 12 is closed, the first outlet of the three-way valve 62 is opened, and the second outlet is closed. This mode consists of refrigerant circulation, heating water circulation and heat storage hot water circulation. The working principles of each part of the circulation are as follows.

[0051] Refrigerant circulation: The high-temperature and high-pressure gas refrigerant coming out of the compressor 1 enters the gap between the inner tube and the outer tube in the shell and tube heat exchanger 6 through the four-way valve 2, flows from top to bottom, and performs forced convection heat exchange with the heating return water in a countercurrent manner, transferring heat to the heating return water through the wall of the inner tube. At the same time, the refrigerant also transfers heat to the low-temperature thermal storage hot water around the shell and tube heat exchanger 6 through the wall of the outer tube, thereby realizing the cooling, condensation and supercooling of the high-temperature refrigerant. The refrigerant coming out of the shell and tube heat exchanger 6 is throttled by the throttle valve 4 and becomes a low-temperature and low-pressure liquid, and then enters the air-cooled evaporator 3 to absorb the heat of the outdoor air, evaporate and superheat, and at the same time, the surface of the evaporator slowly frosts, and the low-temperature and low-pressure superheated gas coming out of the air-cooled evaporator 3 is sucked into the air intake of the compressor 1 after passing through the four-way valve 2 and the gas-liquid separator 5.

[0052] Heating water circulation: The heating water coming out of the heating room is pressurized by the first water valve 11 and the water pump 7, and then enters the shell and tube condenser 6 and flows from bottom to top. The heating water heated by the refrigerant enters the heating room through the first water pipe 8, and transfers the heat to the indoor air, thereby achieving heating of the room.

[0053] Thermal storage hot water circulation: The thermal storage hot water absorbs the heat of the refrigerant in the shell and tube heat exchanger 6 in a heat conduction manner and its temperature gradually increases.

[0054] When the system detects that the air-cooled evaporator 3 needs to be defrosted, it first detects whether the temperature of the thermal storage hot water reaches the set value (the set value can be determined according to the actual situation, as long as the water temperature can provide sufficient heat for the system defrosting, such as the set value of 50°C). If it reaches the set value, the system enters the defrost mode; if it does not reach the set value, the thermal storage hot water fast heat storage mode is operated. The working principle of this mode is as follows:

[0055] The first water valve 11 is closed, the second water valve 12 is opened, the first outlet of the three-way valve 62 is closed, and the second outlet is opened. This mode consists of a refrigerant cycle, a heating water cycle, and a thermal storage hot water cycle. The refrigerant cycle process is the same as the refrigerant cycle process in the heating and thermal storage mode, but the heating water cycle and the thermal storage hot water cycle are quite different. In this mode, the heating water cycle stops. The thermal storage hot water cycle works as follows: the thermal storage hot water passes through the second water valve 12, is pressurized by the water pump 7, and enters the shell and tube heat exchanger 6, flows from bottom to top, exchanges heat with the refrigerant in a forced convection manner, and the temperature gradually increases, and then returns to the thermal storage hot water through the second outlet of the three-way valve 62. In this process, all the heat generated by the system is used to heat the thermal storage hot water, so the temperature of the thermal storage hot water can reach the set value in a very short time (such as 1 minute). Since the heating stop time is short, the temperature in the heating room will not drop. When the water temperature of the thermal storage hot water reaches the set value, the system stops running this mode and enters the defrosting mode.

[0056] When the system runs in defrost mode, the four-way valve 2 is reversed, the first water valve 11 is closed, the second water valve 12 is opened, the first outlet of the three-way valve 62 is closed, and the second outlet is opened. This mode consists of a refrigerant circulation, a heating water circulation, and a thermal storage hot water circulation. The working principles of each circulation are as follows.

[0057] Refrigerant circulation: The high-temperature and high-pressure gas refrigerant coming out of the compressor 1 enters the air-cooled evaporator 3 through the four-way valve 2, transfers heat to the frost on the surface of the evaporator to melt it, and the refrigerant coming out of the air-cooled evaporator 3 is throttled by the throttle valve 4, becomes a low-temperature and low-pressure liquid and enters the gap between the inner tube and the outer tube of the shell and tube heat exchanger 6, flows from bottom to top, and performs forced convection heat exchange with the flowing thermal storage hot water in the inner tube, and also exchanges heat with the thermal storage hot water on the outer surface of the shell and tube in a heat conduction manner. The refrigerant absorbs the heat of these two parts of thermal storage hot water and evaporates into superheated gas, which is then sucked into the suction port of the compressor 1 through the four-way valve 2 and the gas-liquid separator 5.

[0058] Heating water circulation: In this mode, the heating water circulation stops and the system stops supplying heat to the heating room.

[0059] Thermal storage hot water circulation: The thermal storage hot water passes through the second water valve 12, is pressurized by the water pump 7, and enters the shell and tube heat exchanger 6, flows from bottom to top, exchanges heat with the refrigerant in a forced convection manner and the temperature gradually decreases, and then returns to the thermal storage hot water through the second outlet of the three-way valve 62. When the system defrosts, the system stops running this mode and enters the heating and thermal storage mode.

[0060] The shell 61 is built with a heat-insulating material with extremely low thermal conductivity, which can effectively reduce the heat dissipation of the stored hot water to the surrounding cold air. The heat-insulating material can be a heat-insulating cotton or a polyurethane heat-insulating material commonly used in the art.

[0061] The beneficial effects of this embodiment are:

[0062] (1) During the heating and heat storage process of the system, the shell and tube heat exchanger acts as a condenser. The high-temperature refrigerant in the gap between the inner tube and the outer tube exchanges heat with the heating water in the inner tube by forced convection. The heat exchange method with the hot water on the surface of the heat exchanger is mainly heat conduction. The thermal conductivity of water is relatively small. Compared with the forced convection heat exchange method, the heat exchange effect of this method is poor. Therefore, most of the heat of the refrigerant is transferred to the heating water. In addition, in order to ensure sufficient heat storage, the system is also equipped with a fast heat storage mode for hot water. In this way, the shell and tube heat exchanger can be used to achieve the purpose of priority heating, waste heat storage and sufficient heat storage.

[0063] (2) During the defrosting process of the system, the shell and tube heat exchanger acts as an evaporator. The low-temperature refrigerant in the gap between the inner tube and the outer tube can not only exchange heat with the hot water flowing in the inner tube by forced convection, but also exchange heat with the hot water on the surface of the shell and tube heat exchanger by disturbance. Because water continuously flows in and out of the hot water, it will disturb the hot water, thereby enhancing the heat exchange effect of the hot water. This will greatly increase the evaporation temperature of the refrigerant, thereby shortening the defrosting time. At the same time, it can avoid absorbing heat from the room during the defrosting period, ensuring the comfort of the room.

[0064] (3) Based on the hollow exterior of the heat exchanger, this embodiment utilizes the volume of the hollow portion to be filled with hot water for heat storage, and does not require the addition of an additional water pump, but only requires the addition of a few valves and water pipes. This can minimize the space occupied and the cost of the unit. Compared with the traditional reverse cycle defrosting technology and the existing heat storage defrosting technology, especially the phase change heat storage defrosting technology, the advantages are very obvious in terms of both cost and effect.

[0065] (4) Most of the condensers used in small and medium-sized air source heat pump water heaters on the current market are shell and tube heat exchangers, and the system must perform a defrost operation when heating in winter. Combined with the advantages of the above embodiment, it is not difficult to imagine that the present embodiment will have a very broad market application prospect, and its related products are also being developed.

[0066] Embodiment 2

[0067] like Figure 3 As shown, the technical solution of this embodiment is different from that of embodiment 1 in that the system heating and heat storage mode also includes a thermal storage hot water slow heat storage cycle, and the working principle of the cycle is: during the system operation of the heating and heat storage mode, when it is detected that the temperature of the heating water coming out of the shell and tube heat exchanger 6 is lower than the set value, the system runs a thermal storage hot water slow heat storage cycle, the first water valve 11, the fourth water valve 15 and the fifth water valve 17 are closed, the second water valve 12 and the third water valve 13 are opened, the heating water circulation stops, and the thermal storage hot water passes through the second water valve 12, is pressurized by the water pump 7, and then enters the third water valve 13. In the upper space of the shell 61, after the process runs for t seconds (the value of t is small, the reason is given below), that is, after most of the volume of the upper space is filled with hot water, the first water valve 11 and the fifth water valve 17 are opened, and the second water valve 12, the third water valve 13 and the fourth water valve 15 are closed, that is, the circulation of heating water is restored. After such a process, part of the hot water stored in the lower space can be transferred to the upper space, so that the contact area between the surface of the shell and tube heat exchanger 6 and the hot water stored will be reduced, thereby reducing the heat transfer from the refrigerant to the hot water stored, and transferring more heat to the heating water in the inner tube.

[0068] In this process, since the water in the inner tube of the shell-and-tube heat exchanger 6 does not flow, the heat exchange effect between the refrigerant and the water becomes poor. In order to avoid the poor condensation of the refrigerant during this period, which leads to the condensation temperature and pressure of the refrigerant being too high, and then causing the system to stop operating due to self-protection due to excessive pressure, the throttle valve opening can be reduced to reduce the circulation flow of the refrigerant, thereby reducing the condensation pressure of the refrigerant to ensure the stable and safe operation of the unit. If the fan used by the compressor 1 and the air-cooled evaporator 3 is a variable frequency motor, a similar effect can be achieved by reducing the frequency of the motor.

[0069] The reason why the time t is taken as a smaller value is given here: the water pump 7 used in this embodiment is mainly used to drive the circulation of heating water. The circulation flow rate of heating water is much larger than the circulation flow rate of thermal storage hot water, and the volume of the upper half space is smaller, about 20% of the lower half space, so the water pump 7 can fill the upper half space with hot water in a very short time.

[0070] When the temperature of the heating water coming out of the shell and tube heat exchanger 6 is higher than the set value, the fourth water valve 15 opens, and the hot water in the upper half of the space enters the lower half of the space through the fourth water pipe 14 and the fifth water pipe 16 in turn under the action of gravity and is then heated.

[0071] Compared with the first embodiment, the present embodiment has the following beneficial effects:

[0072] This embodiment adds a slow heat storage cycle of thermal storage hot water on the basis of the heating and heat storage mode of the first embodiment. In this way, when the system is running in the heating and heat storage mode, if it is detected that the outlet water temperature of the shell and tube heat exchanger 6 is lower than the set value, the system can transfer more heat of the high-temperature refrigerant to the heating water by running the slow heat storage cycle of thermal storage hot water, thereby achieving the purpose of priority heating.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An air source heat pump hot water heat storage defrosting system based on a shell and tube heat exchanger, characterized in that: It includes heating water circulation module, heat storage module, refrigerant circulation module and heat exchange module; The refrigerant circulation module is connected to the heat exchange module, the heating water circulation module is connected to the heat exchange module, and the refrigerant circulation module and the heating water circulation module transfer heat through the heat exchange module; The heat exchange module is arranged in the heat storage module, and the heat storage module is used to store heat through the heat exchange module; The heat storage medium in the heat storage module includes water; The heating water circulation module comprises a first water pipe (8), a second water pipe (9), a first water valve (11), a fifth water valve (17), a three-way valve (62), and a water pump (7); One end of the first water pipe (8) is connected to the heat exchange module via a three-way valve (62), and the other end is used to transport heating water to the user; The heating return water passes through the second water pipe (9), the first water valve (11), and then is pressurized by the water pump (7) and returned to the heat exchange module through the fifth water valve (17); The heat storage module comprises a shell (61), a partition (18) is further arranged in the shell (61), the partition (18) divides the inner cavity of the shell (61) into an upper cavity and a lower cavity, and the upper cavity and the lower cavity are filled with a heat storage medium; A heat-insulating material layer is provided between the inner wall and the outer wall of the outer shell (61); A conduction unit is provided between the upper cavity and the lower cavity, and the heat storage medium is transferred between the upper cavity and the lower cavity through the conduction unit; The conduction unit comprises a fourth water pipe (14), a fifth water pipe (16), a third water valve (13), and a fourth water valve (15); The fourth water pipe (14) is arranged to penetrate the partition plate (18), and the upper end opening of the fourth water pipe (14) is communicated with the upper cavity; The middle part of the fourth water pipe (14) is connected to the fourth water valve (15) through the fifth water pipe (16), and the end of the fourth water valve (15) away from the fifth water pipe (16) is connected to the lower cavity; The lower end of the fourth water pipe (14) is connected to the water outlet of the water pump (7) through the third water valve (13); The conduction unit further comprises a third water pipe (10) and a second water valve (12); one end of the third water pipe (10) is in communication with the interior of the lower cavity, and the other end is in communication with the second water pipe (9) located between the first water valve (11) and the water pump (7); the second water valve (12) is arranged on the pipeline of the third water pipe (10); The heat exchange module comprises a shell and tube heat exchanger (6), the shell and tube heat exchanger (6) comprises an inner tube and an outer tube, and an internal hollow portion is provided between the inner tube and the outer tube; The outer middle cavity portion of the shell and tube heat exchanger (6) is filled with a heat storage medium; The upper part of the shell and tube heat exchanger (6) is an inlet end, and the lower part is an outlet end; The inner tube water outlet located at the inlet end is connected to the first water pipe (8) through a three-way valve (62), the inlet end of the three-way valve (62) is in communication with the inner tube water outlet, the first water outlet of the three-way valve (62) is in communication with the inlet of the first water pipe (8), and the second water outlet of the three-way valve (62) is in communication with the heat storage medium located in the lower cavity; The heating return water is input to the inner pipe water inlet located at the outlet end through the fifth water valve (17); The refrigerant is input into the heat exchange module through the internal hollow portion inlet located at the inlet end; The refrigerant is returned to the refrigerant circulation module through the internal hollow outlet located at the outlet end.

2. The air source heat pump hot water thermal storage defrosting system based on a shell and tube heat exchanger according to claim 1, characterized in that: The refrigerant circulation module comprises a compressor (1), a four-way valve (2), an air-cooled evaporator (3), a throttle valve (4), and a gas-liquid separator (5); The refrigerant transported back through the outlet of the internal hollow portion of the heat exchange module is connected to the inlet end of the throttle valve (4) through a pipeline; The inlet of the air-cooled evaporator (3) is connected to the outlet of the throttle valve (4); The refrigerant coming out of the outlet of the air-cooled evaporator (3) passes through the four-way valve (2) and the gas-liquid separator (5) and is sucked into the air intake of the compressor (1); The refrigerant output by the compressor (1) is delivered to the heat exchange module through the four-way valve (2) and the inlet of the internal hollow portion.

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