KR101368362B1 - Cooling and heating system using ground source - Google Patents

Abstract

The present invention relates to an excellent air conditioning system using geothermal heat which enhances heat exchanging efficiency by altering a structure of the heat exchanging pipe buried under the ground. The air conditioning system using geothermal heat comprises the heat exchanging pipe and a heat pump. The heat exchanging pipe is buried at a certain depth underground, is linked to demand sources, and absorbs or radiates geothermal heat. The heat pump, joined with the heat exchanging pipe, provides air conditioning to the demand sources using radiation heat or condensation heat supplied through the heat exchanging pipe. The heat exchanging pipe is characterized by slits which are formed on an outer surface or an inner surface of the pipe in a U-shape and which are located lengthwise with certain intervals.

Description

COOLING AND HEATING SYSTEM USING GROUND SOURCE}

The present invention relates to a cooling and heating system using geothermal heat, and more particularly to a cooling and heating system using geothermal heat to improve the heat exchange efficiency by changing the structure of the heat exchange pipe.

Generally, energy sources used in home and industrial air-conditioning are fossil fuels such as petroleum and natural gas or nuclear fuels. The use of these energy sources not only causes major pollution of the environment, but also has a limited amount of reserves. It is actively underway.

As such energy sources used for cooling and heating, fossil fuels such as coal, oil, and natural gas are used, or energy produced using these fossil fuels or nuclear power is mainly used.

However, since fossil fuels have a disadvantage of polluting the water quality and the environment due to various pollutants generated in the combustion process, in recent years, development of alternative energy capable of replacing them has been actively carried out.

Among these alternative energies, research on wind, solar, geothermal, etc., which have infinite energy sources, and air-conditioning devices using them are used. These energy sources have the advantage of obtaining energy with little effect on air pollution and climate change. On the other hand, the energy density is very low.

In particular, in order to obtain energy using wind and solar heat, a large area must be secured along with the limit of the installation site. These devices have a small energy production capacity per unit and are expensive to install and maintain.

Geothermal energy, which is a member of alternative energy, is used for power generation by using geothermal heat in the deep underground, and it is also applied to air-conditioning system using geothermal heat of 10 ~ 20 ℃, which is applied to air-conditioning technology of buildings, etc. In this case, energy savings of up to 40% or more, and energy generation costs of 40 to 70% are known, compared to conventional heating and cooling devices.

The geothermal heating and cooling system using geothermal heat, which is an electric device that uses natural heat storage such as groundwater for the purpose of cooling and heating in buildings, is equipped with an underground heat exchanger, which emits heat to the ground in the summer season and from the ground in the winter season. By absorbing heat, the cooling and heating performance is not lowered by the geothermal temperature that is maintained at a constant temperature at 10 to 20 ° C throughout the year, so that stable operation is possible.

Therefore, many air-conditioning and heating devices using geothermal energy, which require relatively low cost for installation and maintenance, are used. This is a technology using underground thermal energy having a temperature of 10 to 20 ° C.

Commonly used geothermal heating and cooling system is composed of a heat exchange pipe for recovering the geothermal heat, and a heat pump for cooling and heating by moving the geothermal heat recovered from the heat exchange pipe to the required place.

1 is a configuration diagram schematically showing a cooling and heating system using geothermal heat according to the prior art.

As shown in FIG. 1, the air-conditioning and heating system using geothermal heat according to the prior art excavates a plurality of boreholes to a depth of 150 to 200 m or more in the soil layer on the ground side, and heat-exchanges to supply geothermal water into the respective boreholes. The pipe 20 is embedded.

Geothermal water supplied through the heat exchange pipe 20 is provided with a heat pump 30 to move to the demand destination (10) required to perform cooling and heating.

The air-conditioning and heating system using geothermal heat according to the related art, which is configured as described above, is configured to perform geothermal heating by receiving geothermal water through U-shaped heat exchange pipes 20 embedded in the ground by performing geothermal heat as a heat source.

Such cooling and heating forms a circulating cycle with the U-shaped heat exchange pipes 20, and is provided with an evaporator and a condenser connected to the geothermal water obtained from the cooling and heating heat pump 30, and the geothermal water is the cooling and heating heat pump 30. It forms a circulation cycle with the heat exchanger (not shown) connected to the heating and cooling place is installed to perform the cooling and heating or heat supply to the outside air to supply the hot water.

The heat exchange pipe 20 is made of polyethylene (HDPE) in consideration of durability.

However, in the air-conditioning system using geothermal heat according to the prior art as described above, since the heat exchange pipe is made of polyethylene, sufficient heat exchange is not performed, and thus heat exchange efficiency is inferior. Accordingly, in the related art, in order to increase the heat exchange efficiency, the construction depth of the heat exchange pipe cannot be deeply formed to a maximum of 150 to 200 m or more, and the required cost of the raw materials also increases.

An object of the present invention is to provide a cooling and heating system using excellent geothermal heat to improve the heat exchange efficiency by changing the structure of the heat exchange pipe buried underground to solve the above problems.

Geothermal heating and cooling system according to the present invention for achieving the above object is a heat exchange pipe buried to a predetermined depth from the ground and connected to the demand installed on the ground and absorbs geothermal heat or discharges heat into the ground, and the heat exchange pipe And heat pumps for heating and cooling the demand by using heat generated from the geothermal water or condensation heat supplied through the heat exchange pipes, wherein the heat exchange pipes are spaced at regular intervals in the longitudinal direction on the outer or inner surfaces of the U-shaped pipes. It is characterized in that having a plurality of slit grooves.

In addition, the air-conditioning and heating system using geothermal heat according to another embodiment of the present invention is buried in a predetermined depth from the ground connected to the demand destination installed on the ground, and absorbs heat or discharges heat into the ground, and the heat exchange pipe And a heat pump for cooling and heating the demand destination by using the heat of the geothermal water supplied through the heat exchange pipe or the heat of condensation, wherein the heat exchange pipe has a spiral slit groove formed in one direction on the inner surface of the U-shaped pipe. It is characterized by being.

Geothermal heating and cooling system according to the present invention has the following effects.

First, by forming a plurality of slit grooves in the longitudinal direction on the outer or inner surface of the heat exchange pipe can increase the contact area of the geothermal water can improve the heat exchange efficiency.

Second, by forming a slit groove of the spiral structure inside the heat exchange pipe to quickly maintain the flow of geothermal water can improve the heat exchange efficiency.

Third, the heat exchange efficiency can be improved by forming a plurality of slit grooves in the longitudinal direction on the outer surface or the inner surface of the heat exchange pipe and connecting the plurality of heat exchange pipes with a connection member made of a metal having excellent thermal conductivity.

Fourth, by forming a plurality of slit grooves in the longitudinal direction on the outer surface or the inner surface of the heat exchange pipe, and by forming a support member between the U-shaped heat exchange pipe to maintain a constant spacing of the heat exchange pipe can improve heat exchange efficiency.

Fifth, by forming a plurality of slit grooves in the longitudinal direction on the outer surface or the inner surface of the heat exchange pipe and by differently configuring the diameter of one side and the other side of the U-shaped heat exchange pipe, the flow rate of geothermal water is further improved to further improve heat exchange efficiency. You can.

1 is a schematic view showing a cooling and heating system using geothermal heat according to the prior art
2 is a schematic view showing a cooling and heating system using geothermal heat according to the present invention
3 is a plan view showing a first embodiment of the heat exchange pipe in the geothermal heating and cooling system of Figure 2
Figure 4 is a plan view showing a second embodiment of the heat exchange pipe in the geothermal heating and cooling system of Figure 2
5 is a plan view showing a third embodiment of the heat exchange pipe in the air-conditioning system using the geothermal heat of FIG.
6 is a plan view showing a fourth embodiment of the heat exchange pipe in the air-conditioning system using geothermal heat of FIG.
7 is a plan view showing a fifth embodiment of the heat exchange pipe in the air-conditioning system using geothermal heat of FIG.
8 is a view for explaining a slit groove of a heat exchange pipe according to each embodiment of FIGS. 3 to 7.

Hereinafter, with reference to the accompanying drawings, a heating and cooling system using geothermal heat according to an embodiment of the present invention will be described in detail. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

In addition, the same or corresponding components are denoted by the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted. For convenience of explanation, the size and shape of each constituent member shown may be exaggerated or reduced have.

Figure 2 is a schematic view showing a cooling and heating system using geothermal heat according to the present invention, Figure 3 is a plan view showing a first embodiment of a heat exchange pipe in the cooling and heating system using the geothermal heat of FIG.

As shown in FIGS. 2 and 3, the air-conditioning and heating system 100 using geothermal heat according to the present invention includes a demand destination 110, a heat pump 120, a heat exchange pipe 130, and a heat storage tank 140. have.

Here, the demand destination 110 refers to a space in which people or livestock live and work for a predetermined time, such as a company or a public office, with a certain number of square meters.

The heat pump 120 is a general well-known technique, but is not specifically illustrated and described. An evaporator for evaporating a refrigerant, a compressor for compressing a refrigerant evaporated from the evaporator, and a high temperature and high pressure refrigerant are discharged. The discharged refrigerant has a condenser and an expansion valve that flows in and condenses.

That is, the heat pump 120 refers to a cooling and heating device that transfers a low temperature heat source to a high temperature or a high temperature heat source to a low temperature by using heat of a refrigerant or heat of condensation. The heat pump 120 includes an outdoor unit having a compressor and an outdoor exchanger, and an indoor unit including an expansion valve and an indoor exchanger.

The heat exchange pipe 130 is composed of a U-shaped pipe embedded in the ground and the pump is provided to circulate the geothermal water to the heat pump 120 or the heat storage tank 140 along the geothermal recovery pipe extending from the pipe It is.

The heat exchange pipe 130 is formed by drilling a ground surface to a depth of 100 ~ 150M to form a borehole, inserting a U-shaped heat exchange pipe 130 into the borehole.

On the other hand, among the U-shaped pipes constituting the heat exchange pipe 130, the diameter of one side and the other side may be configured differently to vary the flow rate of geothermal water.

For example, the geothermal water used by configuring the pipe diameter of the geothermal water used for cooling and heating in the demand destination 110 is smaller than the pipe diameter into which the geothermal water flows toward the heat pump 120 or the heat storage tank 140. By rapidly advancing the flow rate of the geothermal water supplied to the heat pump 120 or the heat storage tank 140 to slow the flow rate of the geothermal water can be lowered or increased.

As such, the geothermal water is circulated along the geothermal recovery tube of the heat exchange pipe 130 by a pump, so that the heat exchange pipe 130 absorbs heat from the ground through heat exchange with the ground to recover the ground heat or the heat pump 120 or the like. Through the heat storage tank 140 is to supply geothermal water of a predetermined temperature (15 ~ 21 ℃).

For example, when the temperature of the geothermal water flowing from the heat exchange pipe 130 is 10 ° C, the heat storage tank 140 raises the temperature of the geothermal water from 15 to 21 ° C through heating and supplies it to the heat pump 120. And, when it is 25 ℃ cooled to 15 ~ 21 ℃ temperature is supplied to the heat pump 120.

The inner and outer surfaces of the heat exchange pipe 130 are provided with a plurality of heat dissipation fins radially laid along the length, the plurality of heat dissipation fins to pass through the inside because it widens the inner and outer surface area of the heat exchange pipe 130 as much as possible The heat exchange efficiency with geothermal heat can be maximized.

The heat storage tank 140 stores the geothermal water introduced from the heat exchange pipe 130 or the geothermal water heat exchanged from the heat pump 120, and the heat exchange pipe 130 through the geothermal recovery pipe as described above. ) Is connected to the heat pump 120.

The geothermal water flowing into the heat storage tank 140 through the heat exchange pipe 130 is heated or cooled to a predetermined temperature to be supplied to the heat pump 120.

For example, when a temperature monitoring sensor (not shown) is attached to the heat storage tank 140 and the temperature of the geothermal water introduced into the heat storage tank 140 through the temperature sensor is less than 15 degrees, the heat storage tank 140. The geothermal water introduced into the heating) is discharged to 15 degrees or more, and when it is 15 to 30 degrees, the geothermal water is discharged immediately without operating the heat storage tank 140 to be used for heating.

Therefore, by compensating the temperature of the geothermal water supplied from the heat exchange pipe 130 to the heat storage tank 140 to 15 ~ 21 ℃ to supply to the heat pump 120 by reducing the operating time of the heat pump 120 and geothermal Cooling and heating efficiency can be optimized.

Here, the heat storage tank 140 measures the temperature of the geothermal water flowing into the ground to compensate the temperature of the geothermal water to a temperature of 15 ~ 21 ℃ through heating or cooling when the geothermal water temperature is lower or higher than the set value Supply to the heat pump 120.

At this time, the heat storage tank 140 is used to receive the power supplied from the solar power generating device (not shown) in normal times, but when the solar power generating device does not generate power from the accumulated power or the electric field system (not shown) The power supplied will be used.

In addition, the heat storage tank 140 can reduce power consumption by producing and using power by itself through solar power during the day when the solar power generation is possible, when installed in a working place for 5 days a week such as a tourism book By storing and using electrical energy produced from photovoltaic devices in an energy storage device (not shown), power consumption can be reduced to a minimum.

The photovoltaic device generates a direct current electricity from a solar cell array that receives sunlight and converts it into alternating current electricity through an inverter, and converts the alternating current electricity through the inverter into a grid with a grid. It also allows the optional power supply.

If the heat storage tank 140 does not operate, the electric energy produced from the photovoltaic device is configured to be charged to an energy storage device (not shown) and used as needed.

The heat pump 120 and the heat storage tank 140 is configured to supply while maintaining geothermal water at 15 ~ 21 ℃ through mutual communication. On the other hand, the heat storage tank 140 is an additional element in the embodiment of the present invention and omitted as necessary and may supply the geothermal water of the ground to the heat pump 120 or the heat storage tank 140 through the heat exchange pipe 130. have.

The heat exchange pipe 130 is composed of a U-shaped straight pipe made of polyethylene terephthalate (hereinafter referred to as PET), and has a plurality of slit grooves 131 having a predetermined distance in the longitudinal direction on the surface of the heat exchange pipe 130. The groundwater in the ground is collected into the slit groove 131 by a capillary phenomenon to further improve the heat exchange efficiency of the geothermal water flowing into or out of the heat exchange pipe 130.

On the other hand, the configuration of the slit groove 131 will be described in more detail later.

Figure 4 is a plan view showing a second embodiment of the heat exchange pipe in the air-conditioning system using the geothermal heat of FIG.

As shown in FIG. 4, the heat exchange pipe 130 according to the second embodiment has a plurality of slit grooves 131 formed on the outer surface of the heat exchange pipe 130 in the first embodiment, but the slit grooves on the inner surface thereof. The same is true except that 131 is formed.

Therefore, the heat exchange efficiency may be improved by increasing the contact area of the geothermal water flowing into or out of the heat exchange pipe 130 according to the second embodiment.

FIG. 5 is a plan view illustrating a third embodiment of a heat exchange pipe in the geothermal heating and cooling system of FIG. 2.

As shown in FIG. 5, the heat exchange pipe 130 according to the third embodiment forms a screw-type slit groove 131 that rotates in one direction on an inner surface of the heat exchange pipe 130 as compared with the second embodiment. Same thing except that.

Therefore, the heat exchange efficiency may be improved by increasing the contact area of the geothermal water flowing into or out of the heat exchange pipe 130 according to the third embodiment, and by allowing the flow of geothermal water to flow faster through the vortex phenomenon.

FIG. 6 is a plan view illustrating a fourth embodiment of the heat exchange pipe in the geothermal heating and cooling system of FIG. 2.

As shown in FIG. 6, the heat exchange pipe 130 according to the fourth embodiment combines a plurality of connection members 132 made of a metal material having better thermal conductivity than the heat exchange pipe 130 compared to the first embodiment. Same thing except that.

Here, the U-shaped heat exchange pipe 130 heats or lowers the heat more rapidly with respect to geothermal water in the ground in a state in which the connection member 132 of polyethylene material and metal material having different thermal conductivity is connected at regular intervals. It is configured to supply to the pump 120 or the heat storage tank 140.

Meanwhile, the structure of the heat exchange pipe 130 according to the fourth embodiment may be similarly applied to the heat exchange pipe 130 according to the second embodiment.

FIG. 7 is a plan view illustrating a fifth embodiment of a heat exchange pipe in the air conditioning system using geothermal heat of FIG. 2.

As shown in FIG. 7, the heat exchange pipe 130 according to the fifth embodiment maintains the interval of the heat exchange pipe 130 between the U-shaped heat exchange pipes 130 at a constant interval as compared with the fourth embodiment. The same is true except that a plurality of support members 133 are configured.

Here, the U-shaped heat exchange pipe 130 heats or lowers the heat more rapidly with respect to geothermal water in the ground in a state in which the connection member 132 of polyethylene material and metal material having different thermal conductivity is connected at regular intervals. It is configured to supply to the pump 120 or the heat storage tank 140.

The support member 133 is connected between the connection member 132 constituting the U-shaped heat exchange pipe 130 to maintain a constant interval of the U-shaped heat exchange pipe 130 to prevent a decrease in heat exchange efficiency in advance. In addition, the heat exchange efficiency may be improved through the metal connecting member 132.

8 is a view for explaining a slit groove of the heat exchange pipe according to each embodiment of FIGS. 3 to 7.

As shown in FIG. 8, the plurality of slit grooves 131 formed on the inner or outer surface of the heat exchange pipe 130 correspond to the first slit groove 131a and the first slit groove 131a formed on the surface. The second slit groove 131b is configured to be wider than the first slit groove 131a inside the surface.

The first slit groove 131a is symmetrical with a constant curvature from the surface of the pipe constituting the heat exchange pipe 130 to the communicating portion of the second slit groove 131b, and is symmetrical with the second slit groove 131b. The first slit groove 131a is configured to have a constant ratio.

Therefore, the first slit groove 131a is formed to be symmetrical with each other to have a constant curvature, and the second slit groove 131b and the first slit groove 131a are configured to have a constant ratio diameter to further increase the surface tension. By further improving, the heat exchange efficiency can be improved.

Here, the width of the center portion having the widest width among the second slit grooves 131b is 1.6 to 1.8 mm, the radius of curvature R of the second slit grooves 131b is 0.6 to 0.8 mm, The interval of one slit groove 131a has 0.20-0.40 mm.

Between the slit groove 131 and the adjacent slit groove 131 has a 1.6 ~ 2.0 mm relative to the center portion of each slit groove 131, the second slit groove 131b from the upper surface of the pipe The depth to the center is 0.8-1.5 mm, and the depth of the first slit groove 131a is 0.2-0.6 mm from the upper surface of the plate.

In this way, the air-conditioning and heating system using geothermal heat according to the present invention having the heat exchange pipe 130 constitutes a slit groove 131 on the outer or inner surface of the heat exchange pipe 130 embedded in the ground or the metal connecting member 132. ) Can be selectively configured and manufactured in the form of a straight pipe, so that heat exchange of geothermal water can be performed more quickly, thereby improving heat exchange efficiency.

In addition, by forming the support member 133 between the U-shaped heat exchange pipe 130 to maintain the heat exchange pipe 130 at regular intervals, heat exchange efficiency can be improved.

Furthermore, the present invention can reduce the operating cost of the heat pump 120 by allowing the heat pump 120 to be operated according to the set temperature of the heat storage tank 140.

In addition, the present invention is to use the direct generation of electrical energy through the photovoltaic power generation using natural solar energy as the operating energy source, or when the solar power generation is not used to receive a direct energy source from the KEPCO system. The electric energy generated through the solar power generation can be stored in a separate energy storage device when the heating and cooling system is not operating and used as an energy source when needed, thereby minimizing power consumption.

In addition, the present invention, since the depth of the ground to be carried out within 100M when drilling, there is little restriction of the place and can simplify the drilling construction.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Will be apparent to those of ordinary skill in the art.

110: demand source 120: heat pump
130: heat exchange pipe 131: slit groove
132: connecting member 133: support member
140: heat storage tank

Claims (10)

A heat exchange pipe buried to a predetermined depth from the ground and connected to a demand destination installed on the ground and absorbing geothermal heat or releasing heat into the ground;
A heat pump connected to the heat exchange pipe to heat and cool the demand by using heat generated from the geothermal water supplied through the heat exchange pipe or heat of condensation;
It is connected to the heat exchange pipe and the heat pump is configured to include a heat storage tank for supplying a refrigerant at a constant temperature to the heat pump,
The heat exchange pipe has a plurality of slit grooves formed at regular intervals in the longitudinal direction on the outer or inner surface of the U-shaped pipe,
The slit groove is geothermal heat characterized in that it is composed of a first slit groove formed on the surface of the pipe and the second slit groove which is wider than the first slit groove in the surface of the pipe and corresponding to the first slit groove Heating and cooling system. The geothermal heating and cooling system according to claim 1, wherein the heat exchange pipes are formed of a plurality of pipes having a predetermined interval and a plurality of connection members which connect the pipes with a higher thermal conductivity than the pipes. The geothermal heating and cooling system according to claim 2, further comprising a plurality of support members installed to maintain the U-shaped heat exchange pipes at regular intervals. delete The geothermal heating system of claim 2, wherein the U-shaped pipe is made of polyethylene, and the connection member is made of metal. delete According to claim 1, wherein the U-shaped heat exchange pipe geothermal heating and cooling system, characterized in that consisting of pipes having different diameters on one side and the other side. delete delete delete

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