Heat exchange pipe piece model test device and test method

Abstract

The invention provides a heat exchange pipe piece model test device and test method, belongs to the technical field of underground structure experiments, and aims to solve the problems that in the prior art, a model test device is simple in structure, generally only can simulate the heat exchange process under a reduced scale model, the simulation working condition is single, and the simulation result precision is insufficient. Comprising an inner cambered surface box body, an upstream water tank and a downstream water tank which are communicated with the inner cambered surface box body are arranged at the two ends of the inner cambered surface box body in the length direction respectively, a plurality of water outlets with different heights are formed in the end, away from the upstream water tank, of the downstream water tank, and valves are arranged at the water outlets; a pipe piece is arranged at one end of the inner cambered surface box body in the width direction, and the pipe piece is attached to and communicated with the inner cambered surface box body. According to the invention, through the arrangement of the upstream water tank, the downstream water tank and the plurality of water outlets, the device can simulate various environments of the duct piece, including the situation that the surrounding environment of the duct piece has or does not have underground water.

Description

Technical Field

[0001] The invention belongs to the technical field of underground structure construction, and in particular relates to a heat exchange tube segment model test device and a test method. Background Art

[0002] Energy tunnels and energy shafts are a new type of underground energy structure that utilizes geothermal energy, with good environmental and economic benefits. Compared with conventional tunnels or shafts, the main difference is that heat exchange tubes are pre-buried in the prefabricated pipe segments. However, due to the late start of energy tunnels and energy shafts, domestic research on them is still in its initial stage, and the research on the heat exchange efficiency of energy tunnels and energy shafts also mainly refers to the relevant results of energy piles, and no model test method for the heat exchange performance of energy tunnels and energy shafts has been formed.

[0003] The use of model tests to study the geothermal energy development capabilities of energy tunnels and energy shafts has strong practical application significance. The heat transfer performance of heat exchange tube segments in prefabricated energy tunnels and energy shafts mainly depends on factors such as heat transfer medium flow rate, inflow temperature, stratum properties, and groundwater seepage;

[0004] The existing model test devices are all scaled test equipment, simulating a single-loop working condition. Moreover, since they cannot fully meet the similarity ratios of heat transfer and fluid, the simulation results are not accurate enough. Therefore, how to design full-scale model tests in multiple environments for the heat exchange process between the pipe segment and the formation has become a key technical issue in the evaluation and optimization of geothermal energy collection efficiency in energy tunnels and energy shafts. Summary of the invention

[0005] In view of this, the present invention provides a heat exchange tube segment model test device and a test method to solve the problem in the prior art that the structure of the model test device is relatively simple and the result accuracy is insufficient.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A heat exchange tube sheet model test device comprises an inner arc surface box body, wherein the two ends of the inner arc surface box body in the length direction are respectively provided with an upstream water tank and a downstream water tank connected thereto, and the end of the downstream water tank away from the upstream water tank is provided with a plurality of drain ports at different heights, and valves are provided at the drain ports;

[0008] A pipe sheet is provided at one end of the inner arc surface box body in the width direction, and the pipe sheet is in contact with and communicated with the inner arc surface box body.

[0009] In this technical solution, it should be noted that temperature sensors and strain sensors are arranged in layers in the pipe segments, and the upstream water tank has an upstream water tank inlet and an upstream water tank outlet, which are used for water inlet and water outlet respectively. In this solution, the geotechnical materials in the test scene are laid in the outer arc surface box body, and the material height is flush with the heat exchange tube segments. Temperature sensors are arranged in layers in the geotechnical materials for monitoring the temperature. The upstream water tank is used to simulate the upstream groundwater level of the formation. Small holes are evenly arranged on the partition between the upstream water tank and the outer arc surface box body, so that the water in the upstream water tank can be injected into the geotechnical materials in the outer arc surface box body. The downstream water tank is used to simulate the downstream groundwater level of the formation. The water head difference in the upstream and downstream water tanks is used to make the water in the formation flow to simulate the groundwater seepage. Small holes are evenly arranged on the partition between the downstream water tank and the outer arc surface box body, so that the water in the geotechnical materials in the outer arc surface box body can be injected into the downstream water tank. A layer of filter is respectively arranged between the geotechnical materials in the outer arc surface box body and the partitions of the upstream and downstream water tanks to prevent the outer arc surface from leaking. Fine particles of the geotechnical materials in the box body flow into the upstream and downstream water tanks under the action of infiltration. In this scheme, by setting up an upstream water tank, a downstream water tank and several drain outlets, the device can simulate various environments of the pipe segment, including simulating the situation when the surrounding environment of the pipe segment has or does not have groundwater, specifically: when groundwater is not considered, the upstream water tank and the downstream water tank remain water-free; when groundwater is considered to exist, water is injected into the upstream water tank, and then the water flows into the geotechnical materials in the outer arc box body, and then flows into the downstream water tank; it also includes simulating the situation when the surrounding environment of the pipe segment has or does not have groundwater seepage, specifically including: when groundwater infiltration is not considered, the upstream water tank and the downstream water tank maintain the same water level; when groundwater seepage is considered, the water level in the downstream water tank is adjusted by opening and closing the drain outlets at different heights outside the downstream water tank, so that the water level in the upstream water tank is higher than the water level in the downstream water tank, thereby realizing water seepage in the outer arc box body.

[0010] Preferably, an air pump is provided on the upstream water tank, and the air pump is connected to the upstream water tank through an air pipe.

[0011] In this technical solution, it should be noted that when simulating groundwater seepage, when the water pressure in the upstream water tank is insufficient, the pressure can be supplemented by an air pump.

[0012] Preferably, a side of the tube segment away from the inner curved surface box body is provided with an outer curved surface box body that fits and communicates with the inner curved surface box body.

[0013] In this technical solution, it should be noted that the inner arc surface box contains air or water to simulate the conditions of a tunnel or shaft with or without water, respectively, and at least one temperature sensor is arranged in the fluid in the box.

[0014] Preferably, the tube segments are provided with heat exchange tubes, the tube segments are provided with heat exchange tubes, water inlet tanks and water outlet tanks are provided on both sides of the tube segments, the water inlet tank is connected with the heat exchange tubes through a first connecting tube, the first connecting tube is provided with a first water pump, and the water outlet tank is connected with the heat exchange tubes through a second connecting tube. The water inlet tank and the water outlet tank are connected through a third connecting tube and a fourth connecting tube, the third connecting tube is provided with an electric water heater and a second water pump, and the fourth connecting tube is provided with a third water pump. An operating table is provided on one side of the tube segment, a computer and a data acquisition instrument electrically connected to the computer are provided on the operating table, temperature sensors are provided in the tube segment, the electric water heater, the water inlet tank and the water outlet tank, and the computer is electrically connected to the data acquisition instrument, the temperature sensor, the first water pump, the second water pump, the third water pump and the electric water heater.

[0015] In this technical solution, it should be noted that the number of heat exchange tubes can be single, double or multiple. When the number of heat exchange tubes is double, they can be arranged on both sides of the tube sheet; there is no restriction on the form of the pipeline in the tube sheet, and any form of layout scheme is within the scope of this patent. It should be noted that a flow meter is set in each water pump, and the flow rate of each water pump can be adjusted by the test control system. In this solution, the situation when the water temperature of the heat exchange tube in the tube sheet is constant and the situation when the power of the electric water heater is constant can be simulated. When the simulated water inlet temperature is constant, the target temperature T0 of the water inlet tank, the power of the electric water heater and the flow rate of the first water pump are set through the control program in the computer. According to the monitored temperature T1 of the water in the water inlet tank, when the temperature of the water in the water inlet tank reaches the target temperature T0, the power P of the electric water heater, the flow rates of the second water pump and the third water pump are automatically adjusted through the computer control program, so that the temperature T1 of the water in the water inlet tank is always maintained at the target temperature T0; when simulating the constant power situation, the power P of the electric water heater, the flow rates of the first water pump, the second water pump and the third water pump are set through the computer, and the operation is continued until the specified time.

[0016] A heat exchange tube segment model test method, comprising:

[0017] Before the test begins, prefabricate the tube segments, cast the heat exchange tubes and temperature sensors in the tube segments, install the tube segments between the inner arc box and the outer arc box, and seal the contact parts between the outer arc box, the inner arc box and the tube segments. Fill the outer arc box with geotechnical materials to a height flush with the tube segments, and fill the inner arc box with water to a height flush with the tube segments (the inner arc box is filled with water only when there is water in the simulated tunnel or shaft. For tunnels or shafts without water, nothing is filled but air). During the filling process, temperature sensors are laid out at the same time; water is added to the water inlet and outlet tanks to the predetermined water level, and each sensor is connected to the data acquisition instrument through a data cable. The first water pump, the second water pump, the third water pump and the electric water heater are connected to the computer through a data cable;

[0018] Then, a segment model experiment is carried out, which includes:

[0019] (1) Simulate the situation when the surrounding environment of the segment has or does not have groundwater;

[0020] The situation when the simulated environment around the segment has or does not have groundwater specifically includes:

[0021] Without considering groundwater, the upstream and downstream water tanks remain dry;

[0022] When the existence of groundwater is considered, water is injected into the upstream water tank, and the water will flow into the geotechnical material in the outer arc surface box and then flow into the downstream water tank.

[0023] (2) Simulate the situation when the environment around the segment has or does not have groundwater seepage;

[0024] The simulation of the surrounding environment of the segment with or without groundwater seepage specifically includes:

[0025] When groundwater infiltration is not considered, the water level in the upstream tank and the downstream tank is kept the same;

[0026] When groundwater seepage is considered, the water level in the downstream water tank is adjusted by opening and closing the drain outlets at different heights on the outside of the downstream water tank so that the water level in the upstream water tank is higher than that in the downstream water tank. This allows water to seep into the outer curved surface box. When the water pressure in the upstream water tank is insufficient, the pressure can be supplemented by an air pump.

[0027] (3) Simulate the situation when the water temperature of the heat exchange tube in the tube segment is constant;

[0028] When the simulated inlet water temperature is constant, the target temperature T0 of the water inlet tank, the power of the electric water heater and the flow rate of the first water pump are set through the control program in the computer. According to the temperature T1 of the water in the water inlet tank obtained by monitoring, when the temperature of the water in the water inlet tank reaches the target temperature T0, the power P of the electric water heater, the flow rate of the second water pump and the flow rate of the third water pump are automatically adjusted through the computer control program, so that the temperature T1 of the water in the water inlet tank is always maintained at the target temperature T0, wherein the target temperature T0 can be set to different temperatures in different groups of experiments;

[0029] (4) Simulate the situation where the power of the electric water heater is constant.

[0030] When simulating a constant power situation, the power P of the electric water heater, as well as the flow rates of the first water pump, the second water pump, and the third water pump are set through a computer and run continuously for a specified period of time.

[0031] (5) Simulate the constant flow rate of the fluid in the heat exchange tube inside the tube segment;

[0032] When simulating a constant flow rate, the flow rate of the first water pump and the target temperature T0 of the water inlet tank are set by the computer, and the program in the computer will dynamically adjust the ratio of the flow rates of the second water pump and the third water pump, as well as the temperature of the electric water heater, to meet the requirements of both flow rate and temperature. In different groups of tests, the flow rate Q1 can be set to different values.

[0033] (6) Simulate the situation when only the inner curved surface heat exchange tube in the tube segment extracts heat, only the outer curved surface heat exchange tube extracts heat, or both heat exchange tubes extract heat at the same time;

[0034] When it is necessary to simulate the situation of multiple heat exchange tubes, outer arc surface heat exchange tubes and inner arc surface heat exchange tubes are respectively set on the inner and outer arc surfaces in the tube sheet; when simulating heat collection by a single heat exchange tube, only the water pump connecting the working heat exchange tube and the water inlet tank is kept in the working state; when simulating the simultaneous operation of two heat exchange tubes, the water pumps connecting the two heat exchange tubes and the water inlet tank work simultaneously.

[0035] (7) Simulate the conditions of water and no water in the inner curved surface box;

[0036] When simulating the situation where there is water in the inner curved surface box, water is injected into the inner curved surface box until the water level is flush with the pipe segment; when simulating the situation where there is no water in the inner curved surface box, air is kept inside the inner curved surface box.

[0037] (8) Simulate the situation when different geotechnical materials are filled in the outer arc box.

[0038] When simulating different geotechnical materials, after simulating one type of geotechnical material, the geotechnical material in the outer arc surface box is emptied, and then another type of geotechnical material is filled in and then the test is carried out.

[0039] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0040] 1. In the present invention, by providing an upstream water tank, a downstream water tank and a plurality of drainage ports, the device can simulate various environments of the pipe segment, including simulating the situation when the surrounding environment of the pipe segment has or does not have groundwater;

[0041] 2. In the present invention, by providing a water inlet tank, a water outlet tank and various water pumps, the device can also simulate the situation when the water temperature of the heat exchange tube in the tube sheet is constant and the situation when the power of the electric water heater is constant;

[0042] 3. In the present invention, a closed system is formed between the water inlet tank and the water outlet tank, and no water is discharged to the outside of the test device during the test process, thus saving water resources;

[0043] 4. In the present invention, the computer can realize automatic control of the flow rate of each water pump and the temperature or power of the electric water heater in the test, reducing manual operation, saving manpower and reducing errors caused by manual operation;

[0044] 5. In the present invention, the test device is comprehensive in function and can consider various factors affecting the heat exchange efficiency, including the flow rate of the heat exchange fluid, the temperature difference between the heat exchange fluid and the formation, the physical properties of the heat exchange fluid, the formation characteristics, the groundwater flow rate, the fluid characteristics on the curved surface of the pipe segment, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0046] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0047] Figure 2 It is a schematic diagram of the top view of the structure of the present invention;

[0048] Among them: 1-upstream water tank, 101-upstream water tank water inlet, 102-upstream water tank water outlet, 103-air pump, 104-air inlet, 2-outer arc surface box, 3-downstream water tank, 4-inner arc surface box, 5-pipe segment, 501-first connecting pipe, 6-water inlet tank, 7-water outlet tank, 8-data acquisition instrument, 9-computer, 10-electric water heater, C3-second connecting pipe, C5-third connecting pipe, C6-fourth connecting pipe, A1-first water pump, B2-second water pump, B1-third water pump. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0050] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0052] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0053] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0054] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0055] Example 1

[0056] like Figure 1-Figure 2As shown, an embodiment of the present invention discloses a heat exchange tube sheet model test device, including an inner arc surface box body 4, wherein the two ends of the inner arc surface box body 4 in the length direction are respectively provided with an upstream water tank 1 and a downstream water tank 3 connected thereto, and the end of the downstream water tank 3 away from the upstream water tank 1 is provided with a plurality of drain outlets at different heights, and a valve is provided at the drain outlet; one end of the inner arc surface box body 4 in the width direction is provided with a tube sheet, and the tube sheet is in contact with and connected to the inner arc surface box body 4. It should be noted that temperature sensors and strain sensors are arranged in layers in the tube sheet, and the upstream water tank 1 has an upstream water tank inlet 101 and an upstream water tank outlet 102, which are used for water inlet and water outlet, respectively. In this scheme, the geotechnical materials in the test scene are laid in the outer arc surface box body 2, and the material height is flush with the heat exchange tube sheet. Temperature sensors are arranged in layers in the geotechnical materials for monitoring the temperature. The upstream water tank 1 is used to simulate the groundwater level upstream of the stratum, and small strain sensors are evenly arranged on the partition between the upstream water tank 1 and the outer arc surface box body 2. The holes are arranged evenly on the baffle between the downstream water tank 3 and the outer arc surface box body 2, so that the water in the geotechnical material in the outer arc surface box body 2 can be injected into the downstream water tank 3. A layer of filter screen is arranged between the geotechnical material in the outer arc surface box body 2 and the baffle between the upstream and downstream water tanks 3 to prevent the outer arc surface box body from leaking. The fine particles of the geotechnical materials in the body 2 flow into the upstream and downstream water tanks 3 under the action of infiltration. In this solution, by setting the upstream water tank 1, the downstream water tank 3 and a number of drainage ports, the device can simulate various environments of the pipe segment, including the situation when the surrounding environment of the pipe segment has or does not have groundwater. Specifically, when groundwater is not considered, the upstream water tank 1 and the downstream water tank 3 remain water-free; when groundwater is considered, water is injected into the upstream water tank 1, and the water flows into the outer arc surface box 2. The geotechnical materials in the pipe segment flow into the downstream water tank 3; it also includes simulating the situation when the surrounding environment of the pipe segment has or does not have groundwater seepage, specifically including: when groundwater seepage is not considered, the water level in the upstream water tank 1 and the downstream water tank 3 is maintained at the same level; when groundwater seepage is considered, the water level in the downstream water tank 3 is adjusted by opening and closing the drain outlets at different heights outside the downstream water tank 3, so that the water level in the upstream water tank 1 is higher than the water level in the downstream water tank 3, and the seepage of water in the outer arc surface box 2 can be achieved.

[0057] like Figure 1-Figure 2 As shown, in this embodiment, the upstream water tank 1 is provided with an air pump 103, and the air pump 103 is connected to the upstream water tank 1 through an air pipe. It should be noted that when simulating groundwater seepage, when the water pressure in the upstream water tank 1 is insufficient, the air pump 103 can be used to supplement the pressure.

[0058] like Figure 1-Figure 2As shown, in this embodiment, the side of the segment away from the inner curved box 4 is provided with an outer curved box 2 that fits and communicates with the inner curved box 4. It should be noted that the inner curved box 4 is filled with air or water, respectively simulating the conditions of no water and water in the tunnel or shaft, and at least one temperature sensor is provided in the fluid in the box.

[0059] like Figure 1-Figure 2 As shown, in this embodiment, the tube sheet is provided with heat exchange tubes, the tube sheet is provided with heat exchange tubes, the two sides of the tube sheet are provided with water inlet tank 6 and water outlet tank 7 respectively, the water inlet tank 6 is connected with the heat exchange tube through the first connecting pipe 501, the first connecting pipe 501 is provided with a first water pump A1, the water outlet tank 7 is connected with the heat exchange tube through the second connecting pipe C3. The water inlet tank 6 and the water outlet tank 7 are connected through the third connecting pipe C5 and the fourth connecting pipe C6, the third connecting pipe C5 is provided with an electric water heater 10 and a second water pump B2, the fourth connecting pipe C6 is provided with a third water pump. An operating table is provided on one side of the tube sheet, the operating table is provided with a computer 9 and a data acquisition instrument 8 electrically connected to the computer 9, the tube sheet, the electric water heater 10, the water inlet tank 6 and the water outlet tank 7 are all provided with temperature sensors, the computer 9 is electrically connected with the data acquisition instrument 8, the temperature sensor, the first water pump A1, the second water pump B2, the third water pump and the electric water heater 10. It should be noted that the number of heat exchange tubes can be single, double or multiple. When the number of heat exchange tubes is double, they can be arranged on both sides of the tube sheet; there is no restriction on the form of the pipeline in the tube sheet, and any form of layout scheme is within the scope of this patent. It should be noted that a flow meter is set in each water pump, and the flow rate of each water pump can be adjusted by the test control system. In this scheme, the situation when the water temperature of the heat exchange tube in the tube sheet is constant and the situation when the power of the electric water heater 10 is constant can be simulated. When the simulated water inlet temperature is constant, the target temperature T0 of the water inlet tank 6, the power of the electric water heater 10 and the flow rate of the first water pump A1 are set through the control program in the computer 9. According to the temperature T1 of the water in the water inlet tank 6 obtained by monitoring, when the temperature of the water in the water inlet tank 6 reaches the target temperature T0, the power P of the electric water heater 10, the flow rate of the second water pump B2 and the flow rate of the third water pump are automatically adjusted through the control program of the computer 9, so that the temperature T1 of the water in the water inlet tank 6 is always maintained at the target temperature T0; when simulating the constant power situation, the power P of the electric water heater 10, the flow rate of the first water pump A1, the flow rate of the second water pump B2 and the flow rate of the third water pump are set through the computer 9, and the operation is continued until the specified time.

[0060] Example 2

[0061] This embodiment provides a heat exchange tube segment model test method, including:

[0062] Before the test begins, prefabricate the tube segments, cast the heat exchange tubes and temperature sensors in the tube segments 5, install the tube segments 5 between the inner arc box 4 and the outer arc box 2, and seal the contact parts of the outer arc box 2, the inner arc box 4 and the tube segments, fill the outer arc box 2 with geotechnical materials to the same height as the tube segments, and fill the inner arc box 4 with water to the same height as the tube segments (the inner arc box 4 is filled with water only when there is water in the simulated tunnel or shaft, and nothing is filled for tunnels or shafts without water, only air), and temperature sensors are laid out during the filling process; water is added to the water inlet tank 6 and the water outlet tank 7 to the predetermined water level, and each sensor is connected to the data acquisition instrument 8 through a data line, and the first water pump A1, the second water pump B2, the third water pump B1 and the electric water heater 10 are connected to the computer 9 through a data line;

[0063] Then, a segment model experiment is carried out, which includes:

[0064] (1) Simulate the situation when the surrounding environment of the segment has or does not have groundwater;

[0065] The situation when the simulated environment around the segment has or does not have groundwater specifically includes:

[0066] Without considering the groundwater, the upstream water tank 1 and the downstream water tank 3 remain dry;

[0067] When the existence of groundwater is considered, water is injected into the upstream water tank 1 , and the water will flow into the rock and soil materials in the outer arc surface box 2 , and then flow into the downstream water tank 3 .

[0068] (2) Simulate the situation when the environment around the segment has or does not have groundwater seepage;

[0069] The simulation of the surrounding environment of the segment with or without groundwater seepage specifically includes:

[0070] When groundwater infiltration is not considered, the water level in the upstream water tank 1 and the downstream water tank 3 is maintained at the same level;

[0071] When groundwater seepage is considered, the water level in the downstream water tank 3 is adjusted by opening and closing the drain outlets at different heights on the outside of the downstream water tank 3 so that the water level in the upstream water tank 1 is higher than the water level in the downstream water tank 3. This allows water to seep into the outer curved box 2. When the water pressure in the upstream water tank 1 is insufficient, the pressure can be supplemented by the air pump 103.

[0072] (3) Simulate the situation when the water temperature of the heat exchange tube in the tube segment is constant;

[0073] When the simulated inlet water temperature is constant, the target temperature T0 of the water inlet tank 6, the power of the electric water heater 10 and the flow rate of the first water pump A1 are set through the control program in the computer 9. According to the temperature T1 of the water in the water inlet tank 6 obtained by monitoring, when the temperature of the water in the water inlet tank 6 reaches the target temperature T0, the power P of the electric water heater 10, the flow rate of the second water pump B2 and the flow rate of the third water pump B1 are automatically adjusted through the control program of the computer 9, so that the temperature T1 of the water in the water inlet tank 6 is always maintained at the target temperature T0, wherein the target temperature T0 can be set to different temperatures in different groups of experiments;

[0074] (4) Simulate the situation where the power of the electric water heater 10 is constant.

[0075] When simulating a constant power situation, the power P of the electric water heater 10, as well as the flow rates of the first water pump A1, the second water pump B2 and the third water pump are set by the computer 9, and the operation continues until a specified time.

[0076] (5) Simulate the constant flow rate of the fluid in the heat exchange tube inside the tube segment;

[0077] When simulating a constant flow rate, the flow rate of the first water pump A1 and the target temperature T0 of the water inlet tank are set through the computer 9, and the program in the computer 9 will dynamically adjust the ratio of the flow rates of the second water pump B2 and the third water pump B1, as well as the temperature of the electric water heater 10, to simultaneously meet the requirements for flow rate and temperature; in different groups of tests, the flow rate Q1 can be set to different values.

[0078] (6) Simulate the situation when only the inner curved surface heat exchange tube in the tube segment extracts heat, only the outer curved surface heat exchange tube extracts heat, or both heat exchange tubes extract heat at the same time;

[0079] When it is necessary to simulate the situation of multiple heat exchange tubes, outer arc surface heat exchange tubes and inner arc surface heat exchange tubes are respectively arranged on the inner and outer arc surfaces in the tube sheet; when simulating heat collection by a single heat exchange tube, only the water pump connecting the working heat exchange tube and the water inlet tank 6 is kept in the working state; when simulating the simultaneous operation of two heat exchange tubes, the water pumps connecting the two heat exchange tubes and the water inlet tank 6 work simultaneously.

[0080] (7) Simulating the conditions of water and no water in the inner arc surface box 4;

[0081] When simulating the situation where there is water in the inner curved box 4, water is filled into the inner curved box 4 until the water level is flush with the pipe segment; when simulating the situation where there is no water in the inner curved box 4, air is kept in the inner curved box 4.

[0082] (8) Simulate the situation when different geotechnical materials are filled in the outer arc surface box 2.

[0083] When simulating different geotechnical materials, after simulating one type of geotechnical material, the geotechnical material in the outer arc surface box 2 is emptied, and then another type of geotechnical material is filled in and then the test is carried out.

[0084] The circuits, electronic components and modules involved are all prior art and can be fully implemented by those skilled in the art. Needless to say, the content protected by the present invention does not involve improvements to software and methods.

[0085] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0086] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A heat exchange tube segment model test device, characterized in that: It comprises an inner arc-surface box body (2), wherein the two ends of the inner arc-surface box body (2) in the length direction are respectively provided with an upstream water tank (1) and a downstream water tank (3) which are in communication therewith, and the end of the downstream water tank (3) which is away from the upstream water tank (1) is provided with a plurality of drainage ports at different heights, and valves are provided at the drainage ports; A pipe sheet (5) is provided at one end of the inner arc surface box body (2) in the width direction, and the pipe sheet (5) is in contact with and communicates with the inner arc surface box body (2).

2. A heat exchange tube segment model test device according to claim 1, characterized in that: An air pump (103) is provided on the upstream water tank (1), and the air pump (103) is connected to the upstream water tank (1) through an air pipe.

3. A heat exchange tube segment model test device according to claim 1, characterized in that: An outer curved surface box body (4) is provided on one side of the tube segment (5) away from the inner curved surface box body (2) and is in contact with the outer curved surface box body (4).

4. A heat exchange tube segment model test device according to claim 1, characterized in that: Heat exchange tubes are arranged inside the tube sheet (5), and a water inlet box (6) and a water outlet box (7) are respectively arranged on both sides of the tube sheet (5). The water inlet box (6) is connected to the heat exchange tube via a first connecting pipe (501), a first water pump (A1) is arranged on the first connecting pipe (501), and the water outlet box (7) is connected to the heat exchange tube via a second connecting pipe (C3).

5. A heat exchange tube segment model test device according to claim 4, characterized in that: The water inlet tank (6) and the water outlet tank (7) are connected via a third connecting pipe (C5) and a fourth connecting pipe (C6); the third connecting pipe (C5) is provided with an electric water heater (10) and a second water pump (B2); and the fourth connecting pipe (C6) is provided with a third water pump (B1).

6. A heat exchange tube segment model test device according to claim 5, characterized in that: An operating table is provided on one side of the pipe segment (5), and a computer (9) and a data acquisition instrument (8) electrically connected to the computer (9) are provided on the operating table. Temperature sensors are provided in the pipe segment (5), the electric water heater (10), the water inlet tank (6) and the water outlet tank (7). The computer (9) is electrically connected to the data acquisition instrument (8), the temperature sensor, the first water pump (A1), the second water pump (B2), the third water pump (B1) and the electric water heater (10).

7. A heat exchange tube segment model test method, implemented by a heat exchange tube segment (5) model test device according to claims 1 to 6, characterized in that: include: Before the test begins, the tube segments (5) are prefabricated, the heat exchange tubes and the temperature sensors are cast in the tube segments (5), the tube segments (5) are installed between the inner arc box (2) and the outer arc box (4), and the contact parts of the outer arc box (4), the inner arc box (2) and the tube segments (5) are sealed, the outer arc box (4) is filled with geotechnical materials to a height flush with the tube segments (5), the inner arc box (2) is filled with water to a height flush with the tube segments (5), and the temperature sensors are arranged during the filling process; the water inlet tank (6) and the water outlet tank (7) are filled with water to a predetermined water level, and each sensor is connected to the data acquisition instrument (8) via a data line, and the first water pump (A1), the second water pump (B2), the third water pump (B1) and the electric water heater (10) are connected to the computer (9) via a data line; Then, a segment (5) model experiment is performed, wherein the segment (5) model experiment includes: Simulating the situation when the surrounding environment of the pipe segment (5) has or does not have groundwater; Simulating the situation when the surrounding environment of the pipe segment (5) has or does not have groundwater seepage; Simulating the situation when the water temperature of the heat exchange tube in the tube segment (5) is constant; Simulating a situation where the power of the electric water heater (10) is constant; Simulating a constant flow rate of the fluid in the heat exchange tube in the tube sheet (5); Simulating the situation in which only the inner arc surface heat exchange tube in the tube segment (5) extracts heat, only the outer arc surface heat exchange tube extracts heat, or both heat exchange tubes extract heat at the same time; Simulating the conditions of water and no water in the inner curved surface box (2); The situation when different rock and soil materials are filled in the outer arc surface box (4) is simulated.

8. A heat exchange tube segment model test method according to claim 7, characterized in that: The situation when the surrounding environment of the simulated pipe segment (5) has or does not have groundwater specifically includes: Without considering groundwater, the upstream water tank (1) and the downstream water tank (3) remain dry; When the presence of groundwater is considered, water is injected into the upstream water tank (1), and the water flows into the rock and soil material in the outer arc surface box (4), and then flows into the downstream water tank (3).

9. A heat exchange tube segment model test method according to claim 7, characterized in that: The simulation of the situation when the surrounding environment of the pipe segment (5) has or does not have groundwater seepage specifically includes: When groundwater infiltration is not considered, the water level in the upstream water tank (1) and the downstream water tank (3) is maintained at the same level; When the existence of groundwater seepage is considered, the water level in the downstream water tank (3) is adjusted by opening and closing the drainage outlets at different heights outside the downstream water tank (3) so that the water level in the upstream water tank (1) is higher than the water level in the downstream water tank (3), thereby achieving water seepage in the outer arc surface box (4). When the water pressure in the upstream water tank (1) is insufficient, the pressure can be supplemented by the air pump (103).

10. A heat exchange tube segment model test method according to claim 7, characterized in that: The situation when the water temperature of the heat exchange tube in the simulated tube sheet (5) is constant specifically includes: When the simulated inlet water temperature is constant, the target temperature T0 of the water inlet tank (6), the power of the electric water heater (10) and the flow rate of the first water pump (A1) are set through the control program in the computer (9). According to the temperature T1 of the water in the water inlet tank (6) obtained by monitoring, when the temperature of the water in the water inlet tank (6) reaches the target temperature T0, the power P of the electric water heater (10), the flow rate of the second water pump (B2) and the flow rate of the third water pump (B1) are automatically adjusted through the control program of the computer (9), so that the temperature T1 of the water in the water inlet tank (6) is always maintained at the target temperature T0, wherein the target temperature T0 can be set to different temperatures in different groups of experiments; The situation of simulating the constant power of the electric water heater (10) specifically includes: When simulating a constant power situation, the power P of the electric water heater (10), as well as the flow rates of the first water pump (A1), the second water pump (B2) and the third water pump (B1) are set by the computer (9), and the operation is continued until a specified time period.

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