Device for enhancing heat exchange efficiency of rock-soil energy storage cyclic utilization system

Abstract

The utility model discloses a device for enhancing the heat exchange efficiency of a rock-soil energy storage recycling system, which relates to the technical field of heat exchange devices and comprises an inner pipe and an outer pipe sleeved outside the inner pipe, the outer side of the outer pipe is provided with filler, the bottom of the outer pipe is connected with a bottom plate, the bottom plate is connected with a through pipe, and the through pipe is provided with a through hole. The top of the through pipe is connected with a heat exchange column, the through pipe communicates with the interior of the heat exchange column, and a flowing groove with a downward opening is formed in the bottom of the through pipe. According to the device for enhancing the heat exchange efficiency of the rock-soil energy storage cyclic utilization system, the through pipe and the heat exchange column are arranged in the outer pipe, high-temperature fluid flowing in the through pipe can enter the heat exchange column, the contact area between the high-temperature fluid and a heat exchange medium is increased through the heat exchange column, and therefore the heat exchange efficiency of the heat exchange medium is improved; and the utilization efficiency of geothermal energy is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of heat exchange devices, and more specifically to a device for enhancing the heat exchange efficiency of a rock and soil energy storage and recycling system. Background Art

[0002] A heat exchange geothermal well is a system that uses underground heat energy for heat exchange. It is mainly used for the development and utilization of geothermal energy, especially in the fields of heating, hot water supply and power generation. This type of geothermal well is designed to extract heat from underground reservoirs efficiently and sustainably while reducing the impact on the environment. The types of geothermal energy currently developed and utilized are mainly divided into shallow geothermal energy, middle geothermal energy and deep geothermal energy. In the utilization of geothermal resources, the buried pipe system has the advantages of not being restricted by groundwater resources, no pollution to the environment, not being affected by external factors such as seasons and climate, and good system stability.

[0003] The Chinese patent application number 201721267485.6 discloses a geothermal well heat exchanger, which includes an outer casing, an inner casing, an upper cementing section cementing layer and a lower cementing section cementing layer; the inner casing is placed inside the outer casing, and the lower end of the inner casing is higher than the lower end of the outer casing; an annular space is formed between the outer wall of the inner casing and the inner wall of the outer casing; the upper end of the outer casing is used to connect the circulating medium inflow pipeline; the upper end of the inner casing is used to connect the circulating medium outflow pipeline; the upper wall of the outer casing is wrapped with the upper cementing section cementing layer; the outer wall of the lower casing and the lower end are wrapped with the lower cementing section cementing layer; the thermal conductivity of the upper cementing section cementing layer is less than the thermal conductivity of the lower cementing section cementing layer. The geothermal well heat exchanger has the following problems when in use:

[0004] 1. The deeper the geothermal well is, the higher the temperature is, so the temperature at the bottom of the heat exchange pipe is the highest. However, the area where the heat exchange medium can exchange heat with the bottom is limited, and the geothermal energy cannot be well utilized;

[0005] 2. When installing the inner tube, it is necessary to keep the inner tube at the axial position of the outer tube to ensure the maximum efficiency of heat exchange. However, the inner tube may be offset during installation and use, resulting in a decrease in heat exchange efficiency and failure to support and position the inner tube well.

[0006] Therefore, it is necessary to propose a device to enhance the heat exchange efficiency of the geotechnical energy storage and recycling system to solve the above problems. Utility Model Content

[0007] In view of the above problems, the utility model provides a device for enhancing the heat exchange efficiency of the rock and soil energy storage and recycling system; it has the function of improving the heat exchange efficiency, and at the same time can provide stable support for the inner pipe and facilitate the coaxial positioning of the inner pipe during installation.

[0008] In order to achieve the above-mentioned purpose, the utility model specifically adopts the following technical solutions:

[0009] A device for enhancing the heat exchange efficiency of a geotechnical energy storage recycling system, comprising an inner tube and an outer tube sleeved outside the inner tube, a filler is arranged on the outer side of the outer tube, a bottom plate is connected to the bottom of the outer tube, a through pipe is connected to the bottom plate, a heat exchange column is connected to the top of the through pipe, the through pipe is connected to the inside of the heat exchange column, and a flow groove with an opening facing downward is arranged at the bottom of the through pipe;

[0010] The interior of the heat exchange column is connected to a vertically arranged baffle, and both sides of the bottom of the baffle are connected to guide plates, and the guide plates are located in the flow groove;

[0011] The top of the bottom plate is connected to a fixing ring, which is located outside the heat exchange column. The bottom of the inner tube is connected to a positioning ring, which is connected to the top of the fixing ring. A water groove is provided at the bottom of the outer ring surface of the fixing ring, and a circular array of water holes is provided at the bottom of the inner tube.

[0012] The inner annular surface of the outer tube is provided with a plurality of sections of spiral convex ribs, and adjacent convex ribs are arranged in opposite directions.

[0013] Preferably, a first conical ring and a second conical ring are arranged on the top of the fixing ring, the height of the first conical ring is lower than that of the second conical ring, the second conical ring is located outside the first conical ring, and an arc groove is arranged between the first conical ring and the second conical ring.

[0014] Preferably, the bottom of the positioning ring is provided with an arc surface corresponding to the arc groove, and the positioning ring is located in the arc groove.

[0015] Preferably, the top of the outer tube is connected to a return water connection device, the return water connection device is connected to a return water pipe, the top of the return water connection device is connected to a bottom flange, the top of the inner tube is connected to a top flange, and the top flange and the bottom flange are connected by bolts.

[0016] Preferably, water-guiding curved surfaces are provided on both sides of the top of the positioning ring.

[0017] Compared with the prior art, the beneficial effects of the utility model are:

[0018] 1. This device is equipped with a through pipe and a heat exchange column in the outer tube. The high-temperature fluid flowing in the through pipe will enter the heat exchange column, and the contact area with the heat exchange medium will be increased through the heat exchange column, thereby improving the heat exchange efficiency of the heat exchange medium and improving the utilization efficiency of geothermal energy.

[0019] 2. This device is provided with a fixing ring at the bottom of the outer tube. The fixing ring can support the inner tube to avoid shaking during the installation and use of the inner tube, thereby improving the convenience of the inner tube installation. At the same time, it can provide stable support for the inner tube during use and is not prone to deviation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the structure of the external pipe and the return water connection device in the utility model;

[0021] Figure 2 It is a schematic diagram of the inner tube and outer tube structure in the utility model;

[0022] Figure 3 It is a schematic diagram of the flow direction of the heat exchange medium in the utility model;

[0023] Figure 4 It is a schematic diagram of the bottom plate and the fixing ring structure of the utility model;

[0024] Figure 5 It is a schematic diagram of the structure of the fixing ring and the positioning ring in the utility model.

[0025] Reference numerals:

[0026] 101. Inner tube; 102. Outer tube; 103. Bottom plate; 104. Through tube; 105. Heat exchange column; 106. Baffle; 107. Guide plate; 108. Fixing ring; 109. Water hole; 110. Raised rib; 111. First conical ring; 112. Second conical ring; 113. Arc groove; 114. Positioning ring; 115. Return water connection device; 116. Bottom flange; 117. Top flange; 118. Water guide arc surface; 119. Flow groove. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] See also Figure 1-5 , a device for enhancing the heat exchange efficiency of a geotechnical energy storage recycling system, comprising an inner tube 101 and an outer tube 102 sleeved outside the inner tube 101, a filler is arranged on the outer side of the outer tube 102, and a bottom plate 103 is connected to the bottom of the outer tube 102;

[0029] The temperature at the bottom of the heat exchange pipe is the highest. The following provides a structure that can increase the heat exchange area at the bottom: Specifically, a through pipe 104 is connected to the bottom plate 103, and the through pipe 104 extends into the outer pipe 102. The flow groove 119 at the bottom of the through pipe 104 is used for the high-temperature fluid in the geothermal rock formation to pass through. When the high-temperature fluid flows through, it exchanges heat with the internal heat exchange medium through the outer wall of the through pipe 104. The top of the through pipe 104 is connected to the heat exchange column 105. The through pipe 104 and the inside of the heat exchange column 105 are connected. The bottom of the through pipe 104 is provided with a flow groove 119 with an opening facing downward;

[0030] refer to Figure 3 and Figure 4 The interior of the heat exchange column 105 is connected with a vertically arranged baffle 106. The top of the baffle 106 does not contact the heat exchange column 105, and the water flow can move to the other side. The bottom of the baffle 106 is connected with guide plates 107 on both sides. The guide plates 107 are located in the flow groove 119. When the high-temperature fluid flows from the flow groove 119, it will be guided by the guide plates 107 to the heat exchange column 105, so as to flow in the heat exchange column 105. The heat exchange column 105 goes deep into the inner tube 101, and the heat exchange area with the heat exchange medium in the inner tube 101 is increased through the heat exchange column 105.

[0031] When the inner tube 101 is installed, it may not be coaxial with the outer tube 102. The following provides a structure that facilitates the installation of the inner tube 101 and can support the inner tube 101: Figure 4 and Figure 5 , a fixing ring 108 is connected to the top of the bottom plate 103, and the fixing ring 108 is located on the outside of the heat exchange column 105. A positioning ring 114 is connected to the bottom of the inner tube 101. When the inner tube 101 is lowered in the outer tube 102, the positioning ring 114 at the bottom will come into contact with the inclined surface of the side wall of the second conical ring 112. As the inner tube 101 is lowered continuously, the positioning ring 114 will slide to the position of the arc groove 113, thereby completing the installation and fixation of the positioning ring 114 and the fixing ring 108. At this time, they are in a coaxial state. The positioning ring 114 is connected to the top of the fixing ring 108. A water groove is provided at the bottom of the outer ring surface of the fixing ring 108, and a circular array of water holes 109 are provided at the bottom of the inner tube 101;

[0032] When the heat exchange medium flows in the outer tube 102, a nearly static fluid layer will be formed close to the tube wall. This is the boundary layer. The following provides a structure that can break the boundary layer: Figure 2 The inner annular surface of the outer tube 102 is provided with multiple sections of spiral ribs 110, and adjacent ribs 110 are arranged in opposite directions. Through the multiple sections of reversely arranged ribs 110, the heat exchange medium will change its flow state when flowing, thereby breaking the boundary layer and improving the heat exchange efficiency of the heat exchange medium.

[0033] Specifically, refer to Figure 4 and Figure 5 The following provides a structure that facilitates the insertion of the positioning ring 114 into the arc groove 113: a first conical ring 111 and a second conical ring 112 are arranged on the top of the fixing ring 108, the height of the first conical ring 111 is lower than the second conical ring 112, the second conical ring 112 is located on the outside of the first conical ring 111, and the positioning ring 114 will first come into contact with the second conical ring 112 during the downward movement, and an arc groove 113 is arranged between the first conical ring 111 and the second conical ring 112.

[0034] Specifically, refer to Figure 5 The bottom of the positioning ring 114 is provided with an arc surface corresponding to the arc groove 113. The inner tube 101 drives the positioning ring 114 to move downward. The arc surface at the bottom of the positioning ring 114 will come into contact with the inclined surface of the second conical ring 112 close to the axis, and then move toward the axis, and then move into the arc groove 113, thereby ensuring that the inner tube 101 and the outer tube 102 are coaxially arranged, and the positioning ring 114 is located in the arc groove 113.

[0035] Specifically, refer to Figure 1 and Figure 2 The top of the outer tube 102 is connected to a return water connection device 115, and a return water pipe is connected to the return water connection device 115. The heat exchange medium is added into the outer tube 102 through the return water pipe. The top of the return water connection device 115 is connected to a bottom flange 116, and the top of the inner tube 101 is connected to a top flange 117. The top flange 117 and the bottom flange 116 are connected by bolts.

[0036] Specifically, taking Figure 3 and Figure 5 Water guiding arc surfaces 118 are provided on both sides of the top of the positioning ring 114 . The water will flow along the water guiding arc surfaces 118 toward the inner tube 101 , then enter the inner tube 101 through the water holes 109 , and then come into contact with the heat exchange column 105 .

[0037] In this embodiment, a well is drilled on the ground, and the outer tube 102 is lowered into the well, and then the inner tube 101 is lowered into the outer tube 102. The positioning ring 114 at the bottom of the inner tube 101 will come into contact with the second conical ring 112, and then move toward the axial position of the outer tube 102, and then fall into the arc groove 113. At this time, the fixed ring 108 can support the inner tube 101. The heat exchange medium will enter the inner tube 101 from the water groove at the bottom of the fixed ring 108 during the flow of the outer tube 102. The heat exchange medium close to the inner tube 101 will also enter the inner tube 101 from the water hole 109. When flowing, it will come into contact with the heat exchange column 105, thereby increasing the heat exchange area and improving the heat exchange amount.

[0038] Finally, the top flange 117 and the bottom flange 116 are connected together by bolts, thereby completing the connection and fixation of the inner tube 101 and the outer tube 102.

[0039] The above-mentioned implementation modes are only preferred implementation modes of the present invention, and cannot be used to limit the protection scope of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A device for enhancing the heat exchange efficiency of a geotechnical energy storage recycling system, comprising an inner tube (101) and an outer tube (102) sleeved outside the inner tube (101), wherein a filler is arranged on the outer side of the outer tube (102), characterized in that: The bottom of the outer tube (102) is connected to a bottom plate (103), the bottom plate (103) is connected to a through tube (104), the top of the through tube (104) is connected to a heat exchange column (105), the through tube (104) and the interior of the heat exchange column (105) are in communication, and a flow groove (119) with an opening facing downward is provided at the bottom of the through tube (104); The interior of the heat exchange column (105) is connected to a vertically arranged baffle (106), and both sides of the bottom of the baffle (106) are connected to guide plates (107), and the guide plates (107) are located in the flow groove (119); The top of the bottom plate (103) is connected to a fixing ring (108), the fixing ring (108) is located outside the heat exchange column (105), the bottom of the inner tube (101) is connected to a positioning ring (114), the positioning ring (114) is connected to the top of the fixing ring (108), the bottom of the outer ring surface of the fixing ring (108) is provided with a water groove, and the bottom of the inner tube (101) is provided with a circumferential array of water holes (109); The inner annular surface of the outer tube (102) is provided with a plurality of sections of spiral convex ribs (110), and adjacent convex ribs (110) are arranged in opposite directions.

2. The device for enhancing the heat exchange efficiency of a geotechnical energy storage recycling system according to claim 1, characterized in that: A first conical ring (111) and a second conical ring (112) are arranged on the top of the fixing ring (108); the height of the first conical ring (111) is lower than that of the second conical ring (112); the second conical ring (112) is located outside the first conical ring (111); and an arc groove (113) is arranged between the first conical ring (111) and the second conical ring (112).

3. The device for enhancing the heat exchange efficiency of a geotechnical energy storage recycling system according to claim 2, characterized in that: The bottom of the positioning ring (114) is provided with an arc-shaped surface corresponding to the arc-shaped groove (113), and the positioning ring (114) is located in the arc-shaped groove (113).

4. The device for enhancing the heat exchange efficiency of a geotechnical energy storage recycling system according to claim 1, characterized in that: The top of the outer tube (102) is connected to a return water connection device (115), a return water pipe is connected to the return water connection device (115), the top of the return water connection device (115) is connected to a bottom flange (116), the top of the inner tube (101) is connected to a top flange (117), and the top flange (117) and the bottom flange (116) are connected by bolts.

5. The device for enhancing the heat exchange efficiency of a geotechnical energy storage and recycling system according to claim 3, characterized in that: Water-guiding arc surfaces (118) are provided on both sides of the top of the positioning ring (114).

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