CN207196995U - A ground source heat pump system - Google Patents

Abstract

The utility model discloses a ground source heat pump system, which comprises a ground source side heat exchange device, a compressor, a four-way valve, an indoor heat exchange device and a first throttling device; the ground source side heat exchange device comprises one or at least two heat exchange tubes which are vertically buried in soil and connected in parallel, and reversible expansion valves are arranged at the bottoms of the heat exchange tubes. The utility model discloses a ground source heat pump system is through making the direct heat transfer of refrigerant and soil in the ground source heat pump system, eliminate the power loss that must because of circulation refrigerant medium, make ground source heat pump system better high-efficient, energy-conservation, bottom through the heat exchange tube of ground source side sets up reversible expansion valve, effectively solve this heat exchange tube bottom and lead to the problem that the refrigerant partially did not go when circulating to the heat exchange tube bottom far away from the compressor distance, can save the quantity of refrigerant simultaneously, improve ground source heat pump system's heat exchange efficiency, reduce ground source heat pump system's initial investment cost and operation cost expense.

Description

A ground source heat pump system

technical field

The utility model relates to the technical field of heat pumps, in particular to a ground source heat pump system.

Background technique

Heat energy is naturally transferred from warmer to cooler places according to natural physical phenomena. There are generally three basic modes of heat transfer, namely conduction, convection and radiation. If the heat pump technology is used, it can also be used in reverse, absorbing heat from a cold place and releasing it to a warm place. This energy exchange process does require certain external energy such as electrical energy. A heat pump refers to a vapor compression refrigeration device that optimizes and efficiently transfers heat energy in two directions. Heat pumps are widely used in heating, ventilation and air conditioning (HVAC) systems. Heat pumps are reversible, that is, they can transfer heat energy from one direction to another to provide heating or cooling to their target interior space.

Heat pumps are used to transfer heat because heat pumps consume less energy than heat pumps transfer and release heat. Heat pump heating is the transfer of heat from the external environment to the internal space using a heat pump. Most of the energy for heating comes from the outside environment, and only a small amount comes from electricity (or some other high-priced energy source used to operate the compressor). With electric heat pumps applied, the transfer of heat energy can be three or four times greater than the electricity consumption, giving the system a coefficient of performance (COP) of 3 or 4, as opposed to a COP of 1 for conventional resistive heaters, i.e. all heat is derived from the input Generation of electrical energy.

In the HVAC industry, heat pumps are used to transfer energy from outside (environmental elements) to interior spaces. These external energy sources can be air, earth and water. Simply put, a heat pump collects heat energy from the outside and brings it indoors for heating purposes. There are three main types of heat pumps, and there are many subcategories according to different physical conditions and situations.

Air Source Heat Pumps (ASHP) – Air is the source of thermal energy for this type of heat pump. This type of heat pump is suitable for heating and cooling in geographical areas that are not too cold. If the outside temperature drops, the available thermal energy will be relatively reduced, thereby reducing the efficiency. When the outside temperature drops below the freezing point of 0°C, frost will form on the external heat collector, which further reduces the heat collection efficiency. However, air source heat pumps are the most common and inexpensive.

Water Source Heat Pump (WSHP) – Water is the source of thermal energy for this type of heat pump. The application of this type of heat pump is limited to the proximity of large bodies of water. These large bodies of water can be lakes, rivers and groundwater. The use of such heat pumps is limited to geographical location.

Ground (Earth) Source Heat Pumps (GSHP) use the underground (earth) as a source of thermal energy. Regardless of geographical location and season, the application of this type of heat pump is extremely reliable. The temperature below 7 meters of the Earth's surface remains relatively constant. This relatively constant subsurface temperature is warmer than winter temperatures on the surface, making it a reliable source of heat. This type of ground-connected heat pump collects heat in two ways. The first method is to circulate a fluid as a medium in the ground, and then use a heat pump to extract heat energy. This circulating fluid system can be open-loop or closed-loop, and the fluid can be water, brine, methyl, alcohol, antifreeze, etc. The second is the direct diffusion geothermal system (DX), that is, the direct use of refrigerants to absorb heat from the ground.

An open-loop system that uses groundwater as a thermal energy source. It should only be used if there is an adequate groundwater source and the local government allows it. Due to the preciousness of this natural resource, many local environmental protection bureaus do not allow its use.

The closed-loop system is to collect heat energy through a 50mm HDPE pipeline buried in the ground through the intermediary fluid. These HDPE pipes must be laid flat in a 2-meter-deep trench, and each 125 to 200 meters of pipe needs to generate one heating or cooling ton. These HDPE pipes can also be inserted vertically into underground boreholes, the depth of these boreholes will be 60 to 200 meters, depending on whether each borehole can produce 1 or 2 tons of cold or heat. The horizontal closed-loop system requires large-scale excavation, while the vertical closed-loop system will need to drill deep wells, which greatly increases the initial investment cost of the ground source heat pump system.

Utility model content

In view of this, a ground source heat pump system provided by the utility model better overcomes the problems and defects of the above-mentioned prior art. By directly exchanging heat between the refrigerant and the soil in the ground source heat pump system, it overcomes the The thermal resistance problem caused by the heat exchange of the cold medium eliminates the power loss required by the circulating cold medium, making the ground source heat pump system more efficient and energy-saving. By setting the reversible expansion valve at the bottom of the heat exchange tube on the ground source side, the effective It solves the problem that the bottom of the heat exchange tube is far away from the compressor, which causes the refrigerant to circulate to the bottom of the heat exchange tube, and part of it cannot go up. At the same time, it can save the amount of refrigerant, improve the heat exchange efficiency of the ground source heat pump system, and reduce The well drilling area reduces the initial investment cost and operating cost of the ground source heat pump system.

A ground source heat pump system, which is a ground source heat pump system in which refrigerant and soil directly exchange heat, including a ground source side heat exchange device, a compressor, a four-way valve, an indoor heat exchange device, and a first throttling device;

The four-way valve has a first valve port, a second valve port, a third valve port and a fourth valve port, the outlet of the compressor is connected to the first valve port of the four-way valve, and the outlet of the compressor is connected to the first valve port of the four-way valve. The inlet is connected to the third valve port of the compressor;

The second valve port of the four-way valve, the indoor heat exchange device, the first throttling device, the ground source side heat exchange device and the fourth valve port of the four-way valve are connected in sequence;

The ground-source side heat exchange device includes one or at least two parallel heat exchange tubes buried vertically in the soil, and a reversible expansion valve is arranged at the bottom of the heat exchange tubes.

Further, the length of the heat exchange tube is 6-10m.

Further, the diameter of the heat exchange tube is 35-40mm.

Further, the heat exchange tube is a U-shaped tube.

Further, a first bypass valve is further included, and the first bypass valve is connected in parallel with the first throttling device to selectively bypass the first throttling device.

Further, the first throttling device is a two-way conduction thermal expansion valve or an electronic expansion valve, and the first bypass valve is a solenoid valve.

Further, it also includes a second throttling device and a second bypass valve, the second bypass valve is connected in parallel with the second throttling device to selectively bypass the second throttling device, and the first throttling device The flow device and the second throttling device are connected in series between the indoor heat exchange device and the ground source side heat exchange device.

Further, both the first throttling device and the second throttling device are thermal expansion valves.

Further, the first bypass valve and the second bypass valve are one-way valves or electromagnetic valves.

Further, a liquid reservoir is also included, and the liquid reservoir is arranged between the first throttling device and the second throttling device.

Compared with the prior art, the beneficial effects of the ground source heat pump system of the present invention are:

(1) The ground source heat pump system of the present invention overcomes the thermal resistance problem caused by the use of cold medium medium for heat exchange by directly exchanging heat between the refrigerant in the ground source heat pump system and the soil, and eliminates the need for circulating cold medium medium. The power loss makes the ground source heat pump system more efficient and energy-saving, and can continuously meet the cooling and heating needs of indoor users. By setting a reversible expansion valve at the bottom of the heat exchange tube on the ground source side, the bottom end of the heat exchange tube is effectively solved. The long distance from the compressor causes the refrigerant to circulate to the bottom of the heat exchange tube and part of it cannot go up. At the same time, it can save the amount of refrigerant used, improve the heat exchange efficiency of the ground source heat pump system, reduce the drilling area, and reduce the ground source. The initial investment cost and operating cost of the heat pump system.

(2) Furthermore, the ground source heat pump system of the utility model provides a larger heat absorption and exchange surface by using a heat exchange tube with a larger diameter; in addition, by shortening the length of the pipeline, the installation and drilling costs are relatively low.

(3) Further, the ground source heat pump system of the present utility model is provided with a bypass valve in parallel with the throttling device, and only needs to open the bypass valve during defrosting, so that the ground source heat pump system does not need to carry out reverse circulation. May be used for defrosting purposes.

In order to make the above-mentioned purpose, features and advantages of the present invention more comprehensible, preferred embodiments are specifically cited below, together with the accompanying drawings, and are described in detail as follows.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following drawings will be briefly introduced in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention. Therefore, it should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained according to these drawings without creative work.

Fig. 1 is a schematic structural diagram of a ground source heat pump system of the present invention.

Description of main component symbols:

100-ground source side heat exchange device;

110-heat exchange tube;

111 - reversible expansion valve;

200 - compressor;

300-four-way valve;

301-the first valve port of the four-way valve;

302-the second valve port of the four-way valve;

303-the third valve port of the four-way valve;

304-the fourth valve port of the four-way valve;

400-indoor heat exchanger;

500-the first throttling device;

600-the first bypass valve;

700-the second throttling device;

800-the second bypass valve;

900 - Reservoir.

Detailed ways

In order to facilitate the understanding of the present utility model, the ground source heat pump system will be described more comprehensively below with reference to the relevant drawings. The preferred embodiment of the ground source heat pump system is given in the accompanying drawings. However, ground source heat pump systems can be implemented in many different forms and are not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the ground source heat pump system more thorough and comprehensive.

Hereinafter, the terms "comprising" or "may include" that may be used in various embodiments of the present invention indicate the presence of disclosed functions, operations or elements, and do not limit one or more functions, operations or elements. increase. In addition, as used in various embodiments of the present invention, the terms "comprising", "having" and their cognates are only intended to represent specific features, numbers, steps, operations, elements, components or combinations of the foregoing , and should not be understood as excluding the existence of one or more other features, numbers, steps, operations, elements, components or combinations of the foregoing or adding one or more features, numbers, steps, operations, elements, Possibility of components or combinations of the foregoing.

In various embodiments of the present invention, the expression "at least one of A or/and B" includes any or all combinations of words listed at the same time. For example, the expression "A or B" or "at least one of A or/and B" may include A, may include B, or may include both A and B.

In describing the present invention, it should be understood that the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical" , "horizontal", "top", "bottom", "inner", "outer" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description , rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the utility model. In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions, and should not be construed as indicating or implying relative importance.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structures, materials or features are included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

In the description of the present utility model, unless otherwise stipulated and limited, it should be noted that the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a mechanical connection or an electrical connection, or it can be The internal communication between two elements may be direct connection or indirect connection through an intermediary. Those of ordinary skill in the art can understand the specific meanings of the above terms according to specific situations. Unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which various embodiments of the present invention belong. The terms (such as those defined in commonly used dictionaries) will be interpreted as having the same meaning as the contextual meaning in the relevant technical field and will not be interpreted as having an idealized meaning or an overly formal meaning, Unless clearly defined in various embodiments of the present invention.

Example

Referring to Fig. 1, the utility model provides a ground source heat pump system, including a ground source side heat exchange device 100, a compressor 200, a four-way valve 300, an indoor heat exchange device 400 and a first throttling device 500.

Specifically, the four-way valve 300 has a first valve port 301, a second valve port 302, a third valve port 303 and a fourth valve port 304, and the outlet of the compressor 200 is connected to the first valve port of the four-way valve 300. A valve port 301 is connected, and the inlet of the compressor 200 is connected with the third valve port 303 of the compressor 200 .

The second valve port 302 of the four-way valve 300 , the indoor heat exchange device 400 , the first throttling device 500 , the ground source side heat exchange device 100 and the fourth valve port 304 of the four-way valve 300 are connected in sequence.

The ground source side heat exchange device 100 includes one or at least two parallel heat exchange tubes 110 buried vertically in the soil, and a reversible expansion valve 111 is provided at the bottom of the heat exchange tubes 110 .

The above-mentioned reversible expansion valve 111 is a bidirectional reversible expansion valve commonly used in the prior art, one direction can convert liquid refrigerant into gas refrigerant, and the other direction allows gas refrigerant to pass directly.

It can be understood that, the number of the above-mentioned heat exchange tubes can be set according to actual conditions.

Preferably, in the embodiment of the present utility model, the length of the heat exchange tube 110 is 6-10m, such as 6m, 7m, 8m, 9m or 10m.

Preferably, the diameter of the heat exchange tube 110 is 35-40mm, such as 36mm, 35mm, 37mm, 38mm, 39mm or 40mm.

Preferably, the heat exchange tube 110 is a U-shaped tube.

Preferably, the heat exchange tube 110 is a copper tube.

It can be seen from the above description that the ground source heat pump system of the present invention works on the following principles:

When used for indoor cooling, the liquid refrigerant discharged from the outlet of the compressor 200 passes through the first valve port 301 of the four-way valve 300 and the second valve port 302 of the four-way valve 300 to enter the indoor heat exchange device 400 directly, thereby cooling The refrigerant passes through the indoor heat exchange device 400, absorbs heat and evaporates to become a gaseous refrigerant, and then the refrigerant flows through the first throttling device and the ground source side heat exchange device 100 in sequence, and the refrigerant enters the heat exchange tube 110 and passes through the heat exchange tube After the reversible expansion valve 111 at the bottom of 110, heat is exchanged with the soil through the pipe wall of the heat exchange tube 110, the refrigerant is condensed into a liquid state to release heat, and the heat is discharged into the soil, and finally the refrigerant passes through the four-way valve 300 in turn. The fourth valve port 304 and the third valve port 303 of the four-way valve 300 return to the compressor 200, thus completing the circulation of the refrigerant in the ground source heat pump system during indoor cooling.

When used for indoor heating, the liquid refrigerant discharged from the outlet of the compressor 200 passes through the first valve port 301 of the four-way valve 300 and the fourth valve port 304 of the four-way valve 300 in sequence and directly enters the ground source side heat exchange device 100, the liquid refrigerant enters the heat exchange tube 110, and the refrigerant exchanges heat with the soil through the tube wall of the ground source side heat exchange device 100, absorbs the heat in the soil, and passes through the reversible expansion valve 111 at the bottom of the heat exchange tube 110 The refrigerant converted into a gaseous state, then directly enters the indoor heat exchange device 400 through the first throttling device, the refrigerant passes through the indoor heat exchange device 400, condenses and releases heat, and finally the refrigerant passes through the second valve port 302 of the four-way valve 300 in turn And the third valve port 303 of the four-way valve 300 returns to the compressor 200, thus completing the circulation of the refrigerant in the ground source heat pump system during indoor heating.

The ground source heat pump system of the utility model overcomes the problem of heat resistance caused by using a cold medium medium for heat exchange by directly exchanging heat between the refrigerant in the ground source heat pump system and the soil, and eliminates the power loss required by the circulation of the cold medium medium, so that The ground source heat pump system is more efficient, energy-saving, and can sustainably meet the needs of indoor users for cooling and heating. By setting the reversible expansion valve 111 at the bottom of the heat exchange tube 110 on the ground source side, the distance between the bottom of the heat exchange tube 110 is effectively solved. The long distance between the compressor 200 leads to the problem that part of the refrigerant cannot go up when it circulates to the bottom of the heat exchange tube 110. At the same time, it can save the amount of refrigerant used, improve the heat exchange efficiency of the ground source heat pump system, reduce the drilling area, and reduce the ground pressure. The operating cost of the source heat pump system.

Preferably, in the embodiment of the present utility model, the ground source heat pump system further includes a first bypass valve 600, and the first bypass valve 600 is connected in parallel with the first throttling device 500 to selectively bypass the first A throttling device 500 .

It should be understood that the first bypass valve 600 can be turned on or off, and when the first bypass valve 600 is opened, the refrigerant passes through the first bypass valve 600, thereby bypassing the first bypass valve 600 in parallel. A throttling device, not passing through the first throttling device. Here, it should be noted that "selectively" refers to turning on or off the first bypass valve 600 according to the required operation mode of the heat pump system.

When defrosting the ground-source side heat exchange device 100, by simply opening the first bypass valve 600, the pressure difference of the refrigerant in the heat pump system can gradually disappear, and the flow rate increases, thus entering the ground-source side heat exchange The hot gas in the device 100 rapidly increases, so that the defrosting speed of the ground-source heat exchange device 100 can be rapidly increased, and no reverse cycle is required during defrosting.

In other words, when the ground source heat pump system needs to be used for indoor cooling or heating, the first bypass valve 600 is closed, so the switching between cooling, heating and defrosting is very convenient.

Preferably, the first throttling device 500 is a bidirectional thermal expansion valve or an electronic expansion valve, and the first expansion valve is a solenoid valve.

Further, the ground source heat pump system also includes a second throttling device 700 and a second bypass valve 800. The second bypass valve 800 is connected in parallel with the second throttling device 700 to selectively bypass the second throttling device 700, in other words, the second bypass valve 800 can be turned on or off, when the second bypass When the valve 800 is opened, the refrigerant passes through the second bypass valve 800, thereby bypassing the second throttling device connected in parallel with the second bypass valve 800, without passing through the first throttling device.

The first throttling device 500 and the second throttling device 700 are connected in series between the indoor heat exchange device 400 and the ground source side heat exchange device 100 .

As mentioned above, it needs to be understood that the ground source heat pump system of the present invention, by setting the first throttling device 500 and the second throttling device 700, and the first bypass valve 600 connected in parallel with the first throttling device 500 and the The second throttling device 700 is connected in parallel with the second bypass valve 800. In the heating mode, the second bypass valve 800 is opened and the first bypass valve 600 is closed. The refrigerant passes through the second bypass valve 800 and the first bypass valve 600 sequentially. The throttling device 500; in the cooling mode, the first bypass valve 600 is opened and the second bypass valve 800 is closed, and the refrigerant passes through the first bypass valve 600 and the second throttling device 700 in sequence; in the defrosting mode, Opening the first bypass valve 600 and the second bypass valve 800 increases the flow rate and temperature of the refrigerant entering the ground-source side heat exchange device 100 , thereby enabling rapid defrosting.

Preferably, both the first throttling device 500 and the second throttling device 700 are thermal expansion valves. Both the first throttling device 500 and the second throttling device 700 may be one-way thermal expansion valves.

Preferably, the first bypass valve 600 and the second bypass valve 800 are one-way valves or solenoid valves.

Preferably, a liquid reservoir 900 is also included, and the liquid reservoir is arranged between the first throttling device 500 and the second throttling device 700 in series.

It can be understood that the liquid receiver 900 is used to store excess refrigerant that does not pass through the throttling device in cooling or heating mode.

In summary, the beneficial effects of the ground source heat pump system of the present invention are:

(1) The ground source heat pump system of the present invention overcomes the thermal resistance problem caused by the use of cold medium medium for heat exchange by directly exchanging heat between the refrigerant in the ground source heat pump system and the soil, and eliminates the need for circulating cold medium medium. The power loss makes the ground source heat pump system more efficient and energy-saving, and can continuously meet the cooling and heating needs of indoor users. By setting a reversible expansion valve at the bottom of the heat exchange tube on the ground source side, the bottom end of the heat exchange tube is effectively solved. The long distance from the compressor causes the refrigerant to circulate to the bottom of the heat exchange tube and part of it cannot go up. At the same time, it can save the amount of refrigerant used, improve the heat exchange efficiency of the ground source heat pump system, reduce the drilling area, and reduce the ground source. The operating costs of the heat pump system.

(2) Furthermore, the ground source heat pump system of the utility model provides a larger heat absorption and exchange surface by using a heat exchange tube with a larger diameter; in addition, by shortening the length of the pipeline, the installation and drilling costs are relatively low.

(3) Further, the ground source heat pump system of the present utility model is provided with a bypass valve in parallel with the throttling device, and only needs to open the bypass valve during defrosting, so that the ground source heat pump system does not need to carry out reverse circulation. May be used for defrosting purposes.

Although terms representing structures are often used above, such as "ground source side heat exchange device", "indoor heat exchange device", "first throttling device", etc., the possibility of using other terms is not excluded. These terms are only used to describe and explain the essence of the utility model more conveniently; interpreting them as any kind of additional limitation is contrary to the spirit of the utility model.

The above is only a specific embodiment of the present utility model, but the scope of protection of the present utility model is not limited thereto. Anyone familiar with the technical field can easily think of changes or changes within the technical scope disclosed by the utility model Replacement should be covered within the protection scope of the present utility model.

Claims (10)

1. a kind of earth-source hot-pump system, it is refrigerant and the earth-source hot-pump system of soil direct heat transfer, it is characterised in that：Including Ground source heat-exchanger rig, compressor, four-way valve, indoor heat-exchanger rig and first throttle device；

The four-way valve has the first valve port, the second valve port, the 3rd valve port and the 4th valve port, the outlet of the compressor with it is described The first valve port connection of four-way valve, the entrance of the compressor are connected with the 3rd valve port of the compressor；

Second valve port of the four-way valve, indoor heat-exchanger rig, first throttle device, source heat-exchanger rig and the four-way valve The 4th valve port be sequentially connected；

Described ground source heat-exchanger rig includes one be vertically embedded in soil or at least two heat exchanger tubes in parallel, the heat exchange The bottom of pipe is provided with reversible expansion valve.

2. earth-source hot-pump system according to claim 1, it is characterised in that：The length of the heat exchanger tube is 6-10m.

3. earth-source hot-pump system according to claim 1, it is characterised in that：A diameter of 35-40mm of the heat exchanger tube.

4. earth-source hot-pump system according to claim 1, it is characterised in that：The heat exchanger tube is U-tube.

5. earth-source hot-pump system according to claim 1, it is characterised in that：Also include the first by-passing valve, by the of described first Port valve is in parallel with first throttle device optionally to bypass the first throttle device.

6. earth-source hot-pump system according to claim 5, it is characterised in that：The first throttle device is two-way admittance Heating power expansion valve or electric expansion valve, first by-passing valve are magnetic valve.

7. earth-source hot-pump system according to claim 5, it is characterised in that：Also include second throttling device and the second bypass Valve, second by-passing valve are in parallel with second throttling device optionally to bypass the second throttling device, the first segment Stream device and the second throttling device are connected between indoor heat-exchanger rig and described ground the source heat-exchanger rig.

8. earth-source hot-pump system according to claim 7, it is characterised in that：The first throttle device and second section It is heating power expansion valve to flow device.

9. earth-source hot-pump system according to claim 7, it is characterised in that：First by-passing valve and second bypass Valve is check valve or magnetic valve.

10. earth-source hot-pump system according to claim 7, it is characterised in that：Also include liquid reservoir, the liquid reservoir is set Between first throttle device and the second throttling device.