Heat storage and supply performance test system for medium-deep layer underground heat exchange technology

Abstract

The utility model is applicable to the technical field of geothermal energy development and utilization, and provides a heat storage and supply performance test system of a middle-deep layer underground heat exchange technology, which comprises a heat storage layer model and an underground heat exchanger model, the underground heat exchanger model comprises a PE inner pipe model and a heat preservation inner pipe model, two grooves are arranged in the heat storage layer model, and the PE inner pipe model is connected with the heat preservation inner pipe model. A PE inner pipe model and a heat preservation inner pipe model are placed in the two grooves respectively, a resistance wire is arranged at the bottom end of the heat storage layer model, and a plurality of evenly-distributed temperature measuring points are further fixedly arranged in the heat storage layer model. The device further comprises a low-temperature constant-temperature water bath device and a high-temperature constant-temperature water bath device, the low-temperature constant-temperature water bath device is fixedly connected with the PE inner pipe model through a first inlet pipe and a first outlet pipe, and the high-temperature constant-temperature water bath device is fixedly connected with the heat preservation inner pipe model through a second inlet pipe and a second outlet pipe. The device has the advantages of meeting actual boundary conditions and being capable of analyzing the heat storage and supply performance of different inner pipe materials.

Description

Technical Field

[0001] The utility model relates to the technical field of geothermal energy development and utilization, in particular to a heat storage and supply performance testing system for a medium-deep underground heat exchange technology. Background Art

[0002] Patent 202211462278.1 proposes a heat exchange experimental system and experimental method for medium-deep casing heat exchangers. The design of an experimental device for layered settings of medium-deep thermal reservoirs is proposed, and the heat exchange test effects of buried pipe heat exchangers with different arrangements of pipe groups are considered to provide theoretical support and basis for construction practice. Detailed design and settings are carried out according to the characteristics of medium-deep thermal reservoirs. A single-tube buried pipe heat exchanger model is used to test the heat exchange effects of the two flow directions of the circulating medium. A buried pipe heat exchanger model with different arrangements of pipe groups is used to test the heat exchange effects of different pipe group arrangements. The medium-deep thermal reservoirs are layered, providing a scientific experimental method for accurately predicting the heat exchange capacity of medium-deep buried pipe heat exchangers.

[0003] Only the performance test of the technology is carried out on the heating aspect. With the continuous exploration of downhole heat exchange technology, it is found that downhole heat exchange technology has a certain heat storage capacity, which requires certain laboratory research and more requirements for the boundary conditions of the technology. For example, the inlet temperature setting of the downhole heat exchanger during the heat storage process and the switching of the operation mode between heat storage and heat supply are not achievable by the current patent conception. There are limitations. Moreover, for the application of heat storage, the combined effect of the inner tube material and the flow direction of the fluid will form a more complex result, which requires relevant experimental tests for analysis. The system proposed in the current patent has not yet considered the influence of the inner tube material, and it is impossible to carry out the influence of different inner tube materials on the heat storage performance in actual engineering, so there are certain limitations.

[0004] Therefore, in view of the above situation, it is urgent to develop a heat storage and supply performance test system for medium-deep downhole heat exchange technology to overcome the shortcomings in current practical applications. Utility Model Content

[0005] The purpose of the embodiments of the utility model is to provide a heat storage and supply performance testing system for medium-deep underground heat exchange technology, aiming to solve the problems raised in the above-mentioned background technology.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A heat storage and supply performance test system for medium-deep downhole heat exchange technology, comprising a heat reservoir model and a downhole heat exchanger model, the downhole heat exchanger model comprising a PE inner tube model and a thermal insulation inner tube model, the outer wall of the heat reservoir model is fixedly provided with protective cotton, two grooves are provided in the heat reservoir model, the PE inner tube model and the thermal insulation inner tube model are respectively placed in the two grooves, a resistance wire is provided at the bottom of the heat reservoir model, the resistance wire is used to simulate the earth's heat flow, and a plurality of uniformly distributed temperature measuring points are also fixedly provided in the heat reservoir model; the system also comprises a low-temperature constant temperature water bath device and a high-temperature constant temperature water bath device, the water outlet end of the low-temperature constant temperature water bath device is fixedly connected to the PE inner tube model through a first inlet pipe, the water inlet end of the low-temperature constant temperature water bath device is fixedly connected to the PE inner tube model through a first outlet pipe, and a first flow regulating valve, a first circulating water pump and a first gate valve are sequentially provided on the side of the first inlet pipe close to the low-temperature constant temperature water bath device, and the first outlet pipe is close to the low-temperature constant temperature water bath. A tenth gate valve is fixedly arranged on one side of the device, the water outlet end of the high-temperature constant temperature water bath device is fixedly connected to the insulation inner tube model through the second inlet pipe, and the water inlet end of the high-temperature constant temperature water bath device is fixedly connected to the insulation inner tube model through the second outlet pipe. A second flow regulating valve, a second circulating water pump and a seventh gate valve are sequentially arranged on the side of the second inlet pipe close to the high-temperature constant temperature water bath device, and a ninth gate valve and a sixth gate valve are sequentially arranged on the side of the second outlet pipe close to the high-temperature constant temperature water bath device. A fifth gate valve and a fourth gate valve are fixedly arranged between the second inlet pipe and the first outlet pipe, and the fifth gate valve and the fourth gate valve are respectively located on both sides of the seventh gate valve, a third gate valve and a second gate valve are fixedly arranged between the second outlet pipe and the first inlet pipe, and one end of the third gate valve is located at the lower side of the eighth gate valve, and the other end of the third gate valve is located between the first gate valve and the first circulating water pump, one end of the second gate valve is located on the left side of the sixth gate valve, and the other end of the second gate valve is located between the first gate valve and the first circulating water pump.

[0008] According to a further technical solution, a first temperature sensor, a first flow sensor and a first pressure sensor are fixedly arranged on the first inlet pipe in sequence, a second temperature sensor, a second flow sensor and a second pressure sensor are arranged on the first outlet pipe in sequence, a fourth temperature sensor, a fourth flow sensor and a fourth pressure sensor are arranged on the second outlet pipe in sequence, and a ninth gate valve, a third flow sensor and a third pressure sensor are arranged on the second inlet pipe in sequence.

[0009] A further technical solution also includes a controller, which is electrically connected to the low-temperature constant temperature water bath device, the high-temperature constant temperature water bath device, the first gate valve, the second gate valve, the third gate valve, the fourth gate valve, the fifth gate valve, the first flow regulating valve, the sixth gate valve, the seventh gate valve, the eighth gate valve, the second flow regulating valve, the ninth gate valve and the tenth gate valve.

[0010] In summary, the embodiments of the present invention have the following beneficial effects compared with the prior art:

[0011] (1) Setting boundary conditions that meet actual operating conditions, including the setting of inlet water temperature, alternating operation of storage and heating, etc.;

[0012] (2) A test model that takes into account different inner tube materials of the downhole heat exchanger is designed. This model can realize the analysis of the storage and heating performance under different inner tube materials. At the same time, it can coordinate and automatically control the test conditions and fluid flow direction under the storage and heating modes to improve the testing efficiency of the system.

[0013] In order to more clearly illustrate the structural features and effects of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the utility model.

[0015] In the figure: 101-PE inner tube model, 102-insulation inner tube model, 2-heat reservoir model, 3-protective cotton, 4-resistance wire, 5-low temperature constant temperature water bath device, 6-high temperature constant temperature water bath device, 7-first circulating water pump, 8-first gate valve, 9-second gate valve, 10-third gate valve, 11-fourth gate valve, 12-fifth gate valve, 13-first flow regulating valve, 14-first temperature sensor, 15-first flow sensor, 16-first pressure sensor, 17-second temperature sensor, 18-second flow sensor Sensor, 19-second pressure sensor, 20-sixth gate valve, 21-seventh gate valve, 22-second circulating water pump, 23-eighth gate valve, 24-second flow regulating valve, 25-ninth gate valve, 26-third flow sensor, 27-third pressure sensor, 28-fourth temperature sensor, 29-fourth flow sensor, 30-fourth pressure sensor, 31-tenth gate valve, 32-controller, 33-temperature measuring point, 34-first outlet pipe, 35-first inlet pipe, 36-second outlet pipe, 37-second inlet pipe. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0017] The specific implementation of the present utility model is described in detail below in conjunction with specific embodiments.

[0018] like Figure 1As shown, the embodiment of the utility model provides a heat storage and supply performance test system for a medium-deep downhole heat exchange technology, including a heat reservoir model 2 and a downhole heat exchanger model (not marked in the figure), the downhole heat exchanger model includes a PE inner tube model 101 and a thermal insulation inner tube model 102, the outer wall of the heat reservoir model 2 is fixedly provided with a protective cotton 3, the heat reservoir model 2 is provided with two grooves (not marked in the figure), the two grooves are respectively placed with a PE inner tube model 101 and a thermal insulation inner tube model 102, the bottom end of the heat reservoir model 2 is provided with a resistance wire 4, the resistance wire 4 is used to simulate the earth's heat flow, The thermal reservoir model 2 is also fixedly provided with a plurality of uniformly distributed temperature measuring points 33, and the temperature measuring points 33 are used to detect the temperature at different heights; it also includes a low-temperature constant temperature water bath device 5 and a high-temperature constant temperature water bath device 6, the water outlet of the low-temperature constant temperature water bath device 5 is fixedly connected to the PE inner tube model 101 through a first inlet pipe 35, the water inlet of the low-temperature constant temperature water bath device 5 is fixedly connected to the PE inner tube model 101 through a first outlet pipe 34, and the first flow regulating valve 13, the first circulating water pump 7 and the first gate valve 8 are sequentially arranged on one side of the first inlet pipe 35 close to the low-temperature constant temperature water bath device 5, the A tenth gate valve 31 is fixedly arranged on the side of the first outlet pipe 34 close to the low-temperature constant-temperature water bath device 5, a water outlet end of the high-temperature constant-temperature water bath device 6 is fixedly connected to the heat-insulating inner tube model 102 via a second inlet pipe 37, a water inlet end of the high-temperature constant-temperature water bath device 6 is fixedly connected to the heat-insulating inner tube model 102 via a second outlet pipe 36, a second flow regulating valve 24, a second circulating water pump 22 and a seventh gate valve 21 are sequentially arranged on the side of the second inlet pipe 37 close to the high-temperature constant-temperature water bath device 6, a ninth gate valve 25 and a sixth gate valve 20 are sequentially arranged on the side of the second outlet pipe 36 close to the high-temperature constant-temperature water bath device 6 A fifth gate valve 12 and a fourth gate valve 11 are fixedly arranged between the second inlet pipe 37 and the first outlet pipe 34, and the fifth gate valve 12 and the fourth gate valve 11 are respectively located on both sides of the seventh gate valve 21, a third gate valve 10 and a second gate valve 9 are fixedly arranged between the second outlet pipe 36 and the first inlet pipe 35, and one end of the third gate valve 10 is located at the lower side of the eighth gate valve 23, and the other end of the third gate valve 10 is located between the first gate valve 8 and the first circulating water pump 7, one end of the second gate valve 9 is located on the left side of the sixth gate valve 20, and the other end of the second gate valve 9 is located between the first gate valve 8 and the first circulating water pump 7.

[0019] Furthermore, the first temperature sensor 14, the first flow sensor 15 and the first pressure sensor 16 are fixedly arranged on the first inlet pipe 35 in sequence, the second temperature sensor 17, the second flow sensor 18 and the second pressure sensor 19 are arranged on the first outlet pipe 34 in sequence, the fourth temperature sensor 28, the fourth flow sensor 29 and the fourth pressure sensor 30 are arranged on the second outlet pipe 36 in sequence, and the ninth gate valve 25, the third flow sensor 26 and the third pressure sensor 27 are arranged on the second inlet pipe 37 in sequence.

[0020] Furthermore, it also includes a controller 32, which is electrically connected to the low-temperature constant temperature water bath device 5, the high-temperature constant temperature water bath device 6, the first gate valve 8, the second gate valve 9, the third gate valve 10, the fourth gate valve 11, the fifth gate valve 12, the first flow regulating valve 13, the sixth gate valve 20, the seventh gate valve 21, the eighth gate valve 23, the second flow regulating valve 24, the ninth gate valve 25 and the tenth gate valve 31.

[0021] In the embodiment of the utility model, the earth heat flow is simulated by the resistance wire 4, the temperature at different heights is detected by the temperature measuring point 33, and the heating performance of the downhole heat exchanger under different circulation flow rates can be tested by adjusting the first flow regulating valve 13 and the second flow regulating valve 24. The temperature, flow rate and pressure of the fluid in the first inlet pipe 35 are detected by the first temperature sensor 14, the first flow sensor 15 and the first pressure sensor 16 respectively, the temperature, flow rate and pressure of the fluid in the first outlet pipe 34 are detected by the second temperature sensor 17, the second flow sensor 18 and the second pressure sensor 19 respectively, the temperature, flow rate and pressure of the fluid in the second inlet pipe 37 are detected by the ninth gate valve 25, the third flow sensor 26 and the third pressure sensor 27 respectively, and the temperature, flow rate and pressure of the fluid in the second outlet pipe 36 are detected by the fourth temperature sensor 28, the fourth flow sensor 29 and the fourth pressure sensor 30 respectively. The actual boundary conditions are met, the storage and heat supply performance of different inner pipe materials can be analyzed, and the test conditions and fluid flow direction in the storage and heat supply modes can be coordinated and automatically controlled.

[0022] The working principle of the utility model is as follows: before the start of the underground heat exchanger storage and heating performance test, the temperature of the heat reservoir model 2 is set, the heat generation is controlled by the power consumption of the resistance wire 4, and then the heat reservoir model 2 is heated, and a temperature gradient is formed for a certain period of time. The temperature in the heat reservoir model 2 can be monitored by the temperature measuring point 33, and then the performance test under different modes is carried out; first, for the test process of the single heating mode, for the PE inner pipe model 101, the first circulating water pump 7, the first gate valve 8 and the tenth gate valve 31 are opened, and the second gate valve 9, the third gate valve 10, the fourth gate valve 11 and the fifth gate valve 12 are closed, and the circulating fluid is from the PE inner pipe model 10 1, and flows out of the inner tube. The heating performance of the downhole heat exchanger under different circulation flow rates can be tested through the first flow regulating valve 13. The performance of the downhole heat exchanger under heating conditions is tested through the first temperature sensor 14, the first flow sensor 15, the first pressure sensor 16, the second temperature sensor 17, the second flow sensor 18, and the second pressure sensor 19. For the thermal insulation inner tube model 102, the first circulation water pump 7, the second gate valve 9, the fifth gate valve 12, and the tenth gate valve 31 are opened, and the first gate valve 8, the third gate valve 10, the sixth gate valve 20, and the seventh gate valve 21 are closed. The circulating fluid flows into the annular cavity of the thermal insulation inner tube model 102, and flows out of the inner tube. The heating performance of the downhole heat exchanger under different circulation flow rates can be tested through the first temperature sensor 14, the first flow sensor 15, the first pressure sensor 16, the second temperature sensor 17, the second flow sensor 18, and the second pressure sensor 19. The heat supply performance of the downhole heat exchanger under different circulation flow rates can be tested by adjusting the first flow regulating valve 13; secondly, for the test process of a single heat storage mode, taking the insulation inner tube model 102 as an example, the second circulation water pump 22, the sixth gate valve 20, the seventh gate valve 21, and the ninth gate valve 25 are opened, and the second gate valve 9, the third gate valve 10, the fourth gate valve 11, the fifth gate valve 12, and the eighth gate valve 23 are closed. The circulating fluid flows into the inner tube of the insulation inner tube model 102 and flows out of the annular cavity. The heating performance of the downhole heat exchanger under different circulation flow rates can be tested by adjusting the second flow regulating valve 24. The third temperature sensor 25 and the third flow sensor 26 are used to measure the heat supply performance of the downhole heat exchanger under different circulation flow rates. , the third pressure sensor 27, the fourth temperature sensor 28, the fourth flow sensor 29 and the fourth pressure sensor 30 cooperate to test the performance of the downhole heat exchanger under heat storage conditions. For the PE inner tube model 101, the second circulating water pump 22, the first gate valve 8, the third gate valve 10, the fourth gate valve 11 and the eighth gate valve 23 are opened, and the second gate valve 9, the fifth gate valve 12, the first flow regulating valve 13, the sixth gate valve 20, the seventh gate valve 21, the ninth gate valve 25 and the tenth gate valve 31 are closed. The circulating fluid flows in from the inner tube of 101 and flows out from the annular cavity. By adjusting the second flow regulating valve 24, the heating performance of the downhole heat exchanger under different circulating flow rates can be tested. In addition, for the alternating operation performance test of heat storage and heat supply, according to the operation time of heat storage and heat supply, the constant temperature water bath device, valves and water pumps are opened by the controller 32 according to the method of single heating mode and single heat storage mode.

[0023] The circuits, electronic components and modules involved are all existing technologies and can be fully implemented by those skilled in the art. Needless to say, the content protected by this utility model does not involve improvements to software and methods.

[0024] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A heat storage and supply performance test system for medium-deep downhole heat exchange technology, including a heat reservoir model and a downhole heat exchanger model, characterized in that: The downhole heat exchanger model includes a PE inner tube model and an insulation inner tube model, the outer wall of the heat reservoir model is fixedly provided with protective cotton, two grooves are provided in the heat reservoir model, the PE inner tube model and the insulation inner tube model are placed in the two grooves respectively, the bottom of the heat reservoir model is provided with a resistance wire, the resistance wire is used to simulate the earth's heat flow, and a plurality of evenly distributed temperature measuring points are fixedly provided in the heat reservoir model; it also includes a low-temperature constant temperature water bath device and a high-temperature constant temperature water bath device, the water outlet end of the low-temperature constant temperature water bath device is fixedly connected to the PE inner tube model through a first inlet pipe, the water inlet end of the low-temperature constant temperature water bath device is fixedly connected to the PE inner tube model through a first outlet pipe, and a first flow regulating valve, a first circulating water pump and a first gate valve are sequentially provided on the side of the first inlet pipe close to the low-temperature constant temperature water bath device, a tenth gate valve is fixedly provided on the side of the first outlet pipe close to the low-temperature constant temperature water bath device, and the high temperature The water outlet of the constant temperature water bath device is fixedly connected to the insulation inner tube model through the second inlet pipe, and the water inlet of the high-temperature constant temperature water bath device is fixedly connected to the insulation inner tube model through the second outlet pipe. The second inlet pipe is provided with a second flow regulating valve, a second circulating water pump and a seventh gate valve in sequence on the side close to the high-temperature constant temperature water bath device, and the second outlet pipe is provided with a ninth gate valve and a sixth gate valve in sequence on the side close to the high-temperature constant temperature water bath device. A fifth gate valve and a fourth gate valve are fixedly provided between the second inlet pipe and the first outlet pipe, and the fifth gate valve and the fourth gate valve are respectively located on both sides of the seventh gate valve, a third gate valve and a second gate valve are fixedly provided between the second outlet pipe and the first inlet pipe, and one end of the third gate valve is located at the lower side of the eighth gate valve, and the other end of the third gate valve is located between the first gate valve and the first circulating water pump, one end of the second gate valve is located on the left side of the sixth gate valve, and the other end of the second gate valve is located between the first gate valve and the first circulating water pump.

2. The heat storage and supply performance testing system of the mid-deep downhole heat exchange technology according to claim 1 is characterized in that: The first inlet pipe is fixedly provided with a first temperature sensor, a first flow sensor and a first pressure sensor in sequence, the first outlet pipe is fixedly provided with a second temperature sensor, a second flow sensor and a second pressure sensor in sequence, the second outlet pipe is fixedly provided with a fourth temperature sensor, a fourth flow sensor and a fourth pressure sensor in sequence, and the second inlet pipe is fixedly provided with a ninth gate valve, a third flow sensor and a third pressure sensor in sequence.

3. The heat storage and supply performance testing system of the mid-deep downhole heat exchange technology according to claim 2 is characterized in that: It also includes a controller, which is electrically connected to the low-temperature constant-temperature water bath device, the high-temperature constant-temperature water bath device, the first gate valve, the second gate valve, the third gate valve, the fourth gate valve, the fifth gate valve, the first flow regulating valve, the sixth gate valve, the seventh gate valve, the eighth gate valve, the second flow regulating valve, the ninth gate valve and the tenth gate valve.

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