Thermal physical parameter layering testing method and instrument

Abstract

This invention discloses a method and instrument for stratified testing of thermal properties, including a protective enclosure containing a testing chamber. The testing chamber houses a heating chamber, a cooling chamber, a thermal regulating pipe, and electrical components. The heating and cooling chambers are connected via the thermal regulating pipe, and the electrical components control the thermal regulating pipe. By adjusting the thermal regulating pipe, three modes are achieved: frequency domain analysis, constant temperature control, and constant power control. This invention allows for flexible access and deployment in confined or construction environments, enabling multi-dimensional thermal response testing of underground energy structures and effective differentiation of heat transfer performance at different heat transfer depths.

Description

Technical Field

[0001] This invention belongs to the field of thermal response testing technology, specifically relating to a method and instrument for stratified testing of thermal property parameters. Background Technology

[0002] Existing thermal response testing of buried pipes is mostly conducted on the surface, with relatively large testing equipment that is easy to install and operate. However, thermal response testing of underground energy structures (such as integrated pipe corridors and tunnels) is often conducted in confined spaces or construction environments. Traditional equipment is bulky, making transportation, installation, and maintenance difficult, which can affect the continuity and reliability of the testing. For structures such as energy piles and energy sidewalls, arranging temperature sensors along the depth of the heat exchange pipes is a cumbersome process, limiting construction efficiency and testing results.

[0003] For underground energy structures such as energy piles and energy sidewalls, a shallow heat exchanger pipe depth represents a shallow stratum, while a large heat exchanger pipe depth represents a deep stratum. Conversely, for underground energy structures such as energy base plates and energy tunnels, a shallow heat exchanger pipe depth represents a small pipe area, while a large heat exchanger pipe depth represents a large pipe area. However, existing technologies are insufficient to meet the requirements for on-site construction and performance evaluation. Summary of the Invention

[0004] The purpose of this invention is to provide a method and instrument for stratified testing of thermal property parameters, which can be flexibly deployed and arranged in narrow or construction environments, enabling multi-dimensional thermal response testing of underground energy structures and effective differentiation of heat transfer performance at different heat transfer depths.

[0005] To achieve the above objectives, the present invention provides a thermophysical parameter stratification testing instrument, including a protective box, a testing chassis installed inside the protective box, a heating chamber, a cooling chamber, a thermal regulating pipe and electrical components installed inside the testing chassis, the heating chamber and the cooling chamber being connected through the thermal regulating pipe, and the electrical components being connected to control the thermal regulating pipe.

[0006] As a further aspect of the present invention: the heat regulation pipe includes pipe section A for connecting the water supply port on the test chassis and pipe section K for connecting the water return port on the test chassis;

[0007] Pipe section A connects several water pumps connected in parallel. The other end of the water pumps is connected to solenoid valves A and B connected in parallel through pipe section B. The other end of solenoid valve A is connected to solenoid valve C. The other end of solenoid valve B is connected to several water tanks in sequence and then connected to solenoid valve D. Solenoid valves C and D are connected to a flow meter. The other end of the flow meter is connected to solenoid valves E and H connected in parallel.

[0008] Pipe section K connects to solenoid valves F and G, which are set in parallel. Solenoid valves E and F are connected to the heating chamber through temperature sensor A. Solenoid valves G and H are connected to the cooling chamber through temperature sensor D. The heating chamber is connected to the cooling chamber in sequence through temperature sensors B and C.

[0009] As a further aspect of the present invention: the heating cavity includes a heating cavity isolation shell, and a heating cavity heat sink is installed at the top center of the heating cavity isolation shell.

[0010] As a further aspect of the present invention: a multi-layered stacked heating assembly is installed inside the heating chamber isolation shell, the heating assembly including a heating plate and a heat exchange plate connected below the heating plate.

[0011] As a further aspect of the present invention: the cooling cavity includes a cooling cavity isolation shell, a cooling cavity radiator is installed at the top center of the cooling cavity isolation shell, and multiple layers of symmetrical cooling components are installed inside the cooling cavity isolation shell.

[0012] As a further aspect of the present invention: the refrigeration assembly includes a refrigeration plate and a heat exchange plate connected to the cold end of the outer side of the refrigeration plate, and heat dissipation fins connected to the hot end of the inner side of the refrigeration plate.

[0013] As a further aspect of the present invention: the electrical components include a heat sink, a power supply, a switching power supply, a relay, a water pump frequency converter, a frequency converter operation panel, a temperature controller, a PLC controller, and a display.

[0014] The power supply is connected to the switching power supply, relay, water pump inverter, and water pump; the switching power supply is connected to the temperature controller, PLC controller, display, and radiator; the inverter operation panel is connected to the water pump inverter.

[0015] As a further embodiment of the present invention: the protective box includes a protective box body, and the two ends of the protective box body are connected to a front cover and a rear cover by protective box screws. The surface of the protective box body is provided with openings corresponding to the heating chamber, the cooling chamber and the electrical components.

[0016] As a further aspect of the present invention: the test chassis includes a test chassis body, a chassis cover is connected to the top of the test chassis body by chassis screws, and slide rails for connecting a protective box are provided on both sides of the test chassis body.

[0017] To achieve the above objectives, the present invention also provides a method for stratified testing of thermophysical parameters, based on the aforementioned thermophysical parameter stratified testing instrument, comprising the following steps:

[0018] S1. Install test heat exchange tubes in the selected underground energy structure area and set the length of the heat exchange tubes. L ;

[0019] S2. Use testing instruments to perform phase calibration on the heat exchange tubes to obtain the critical frequency of water supply temperature fluctuation. f c ;

[0020] S3. Use testing instruments to calibrate the amplitude of the heat exchange tubes to obtain the critical amplitude of the water supply temperature fluctuation.A c ;

[0021] S4. Under constant temperature control mode, restore the temperature in the heat exchange tubes to the initial soil temperature. T soil ;

[0022] S5. Critical frequency of water supply temperature fluctuation obtained from S2 and S3 f c and the critical amplitude of water supply temperature fluctuation A c The system outputs test data on supply water temperature fluctuations and determines the frequency of return water temperature fluctuations relative to the critical frequency of supply water temperature fluctuations. f c Size relationship;

[0023] S6. Determine the current heat exchange tube length based on the judgment result of S5. L Is it suitable? If not, the length of the heat exchange tube needs to be changed. L Then restart the loop iteration from S1.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] 1. The testing instrument has a compact internal structure and a small overall size, allowing it to move in and out of confined spaces or construction environments with ease. This avoids the inconvenience of traditional large testing instruments in terms of handling, installation, and maintenance, effectively improving the continuity and reliability of testing.

[0026] 2. By controlling the heat exchange tube with electrical components, three modes can be combined: frequency domain analysis, constant temperature control, and constant power control, to achieve multi-dimensional thermal response testing of underground energy structures. Unlike common borehole pipe temperature measurement methods, this invention does not require temperature sensors to be arranged along the depth direction of the heat exchange tube. The appropriate length of the heat exchange tube can be determined by the characteristics of the supply and return water temperature waveforms, simplifying the testing process and avoiding the complexity of deploying sensors in different types of underground energy structures.

[0027] 3. This invention utilizes the high homogeneity of concrete in underground energy structures and analyzes the frequency domain differences in the supply and return water temperature waveforms to effectively distinguish the heat exchange performance at different heat exchange depths. In energy piles and energy sidewalls, a smaller heat exchange pipe depth corresponds to shallow strata, while a larger heat exchange pipe depth corresponds to deep strata. In energy base plates and energy tunnels, a smaller heat exchange pipe depth corresponds to a smaller pipe layout area, while a larger heat exchange pipe depth corresponds to a larger pipe layout area. Therefore, this invention can flexibly determine the rationality of the heat exchange pipe layout length in various types of underground energy structures. Attached Figure Description

[0028] Figure 1This is a schematic diagram of the structure of the thermophysical parameter stratification testing instrument of the present invention.

[0029] Figure 2 This is a schematic diagram of the test chassis structure of the thermophysical parameter stratification test instrument of the present invention.

[0030] Figure 3 This is a schematic diagram of the internal structure of the test chamber of the thermophysical parameter stratification test instrument of the present invention.

[0031] Figure 4 This is a schematic diagram of the thermal regulation tube connection structure of the thermophysical parameter stratification testing instrument of the present invention.

[0032] Figure 5 This is a top view of the thermal regulation tube connection structure of the thermophysical parameter stratification testing instrument of the present invention.

[0033] Figure 6 This is a schematic diagram of the thermal regulation tube connection principle of the thermophysical parameter stratification testing instrument of the present invention.

[0034] Figure 7 This is a schematic diagram of the heating cavity structure of the thermophysical parameter stratification testing instrument of the present invention.

[0035] Figure 8 This is a schematic diagram of the cooling chamber structure of the thermophysical parameter stratification testing instrument of the present invention.

[0036] Figure 9 This is a schematic diagram of the heat exchange channel structure of the thermophysical parameter stratification testing instrument of the present invention.

[0037] In the diagram: 1. Protective box, 2. Test chamber, 3. Heat regulating pipe, 4. Heating chamber, 5. Cooling chamber, 6. Electrical components, 7. Front cover of protective box, 8. Protective box body, 9. Rear cover of protective box, 10. Protective box screws, 11. Test chamber body, 12. Slide rail, 13. Top cover of the chamber, 14. Chamber screws.

[0038] 15. Pipe segment A, 16. Pipe segment B, 17. Pipe segment C, 18. Pipe segment D, 19. Pipe segment E, 20. Pipe segment F, 21. Pipe segment G, 22. Pipe segment H, 23. Pipe segment I, 24. Pipe segment J, 25. Pipe segment K;

[0039] 26. Water tank A, 27. Water tank B, 28. Solenoid valve A, 29. Solenoid valve B, 30. Solenoid valve C, 31. Solenoid valve D, 32. Solenoid valve E, 33. Solenoid valve F, 34. Solenoid valve G, 35. Solenoid valve H, 36. Flow meter, 37. Temperature sensor A, 38. Temperature sensor B, 39. Temperature sensor C, 40. Temperature sensor D;

[0040] 41. Heating chamber isolation shell; 42. Heating chamber radiator; 43. Protective plate; 44. Heating plate; 45. Heat exchange plate; 46. Heat exchange channel; 47. Cooling chamber isolation shell; 48. Cooling chamber radiator; 49. Cooling plate; 50. Hot end heat dissipation fins; 51. Dustproof net; 52. Radiator; 53. Power supply; 54. Switching power supply; 55. Relay; 56. Water pump frequency converter; 57. Water pump A; 58. Water pump B; 59. Frequency converter operation panel; 60. Temperature controller; 61. PLC controller; 62. Display. Detailed Implementation

[0041] The invention will now be further described with reference to the accompanying drawings.

[0042] like Figure 1 As shown, a thermophysical parameter stratification testing instrument includes a protective box 1, a testing chamber 2 installed inside the protective box 1, a heating chamber 4, a cooling chamber 5, a heat regulating pipe 3 and an electrical component 6 installed inside the testing chamber 2, the heating chamber 4 and the cooling chamber 5 are connected through the heat regulating pipe 3, and the electrical component 6 is connected to control the heat regulating pipe 3;

[0043] like Figures 4 to 6 As shown, the heat regulation pipe 3 includes pipe section A15 for connecting to the water supply port on the test chamber 2 and pipe section K25 for connecting to the water return port on the test chamber 2.

[0044] Pipe section A15 connects several water pumps arranged in parallel. The other end of the water pump is connected to solenoid valves A28 and B29 arranged in parallel through pipe section B16. The other end of solenoid valve A28 is connected to solenoid valve C30. The other end of solenoid valve B29 is connected to several water tanks in sequence and then connected to solenoid valve D31. Solenoid valves C30 and D31 are connected to flow meter 36. The other end of flow meter 36 is connected to solenoid valves E32 and H35 arranged in parallel.

[0045] Pipe section K25 is connected to solenoid valves F33 and G34, which are set in parallel. Solenoid valves E32 and F33 are connected to heating chamber 4 through temperature sensor A37. Solenoid valves G34 and H35 are connected to cooling chamber 5 through temperature sensor D40. Heating chamber 4 is connected to cooling chamber 5 in sequence through temperature sensor B38 and temperature sensor C39.

[0046] Preferably, the water pumps include water pump A57 and water pump B58 connected in parallel, and the water tanks include water tank A26 and water tank B27 connected in parallel.

[0047] Specific connection methods are as follows: Figures 4-6As shown, the water supply port on the test chamber 11 is connected to water pumps A57 and B58 via pipe section A15, and then to solenoid valves A28 and B29 via pipe section B16; solenoid valve A28 is connected to solenoid valve C30 via pipe section C17, forming a pipeline for frequency domain analysis or constant power control; solenoid valve B29 is connected to water tank A26 via pipe section D18, water tank A26 is connected to water tank B27 via pipe section E19, and water tank B27 is connected to solenoid valve D31 via pipe section F20, forming a buffer water tank pipeline for constant temperature control; solenoid valve C30 and solenoid valve D31 are connected to flow meter 36 via pipe section G21; flow meter 36 is connected to solenoid valve E32 and solenoid valve H35 via pipe section H22; solenoid valve E32 and solenoid valve F33 are connected to heating chamber 4 via temperature sensor A37; heating chamber 4 is connected to cooling chamber 5 via temperature sensor B38 and temperature sensor C39; cooling chamber 5 is connected to solenoid valve G34 and solenoid valve H35 via temperature sensor D40 and pipe section J24; solenoid valve F33 and solenoid valve G34 are connected to the return water port on the test chamber 11 via pipe section K25.

[0048] Among them, pipe section A15, water pumps A57 and B58, pipe section B16, solenoid valve A28, pipe section C17, solenoid valve C30, pipe section G21, flow meter 36, pipe section H22, solenoid valve E32, pipe section I23, temperature sensor A37, heating chamber 4, temperature sensor B38, temperature sensor C39, cooling chamber 5, temperature sensor D40, solenoid valve G34, pipe section H22 and pipe section K25 constitute the heat regulation pipe 3 for heating conditions under frequency domain analysis and constant power control.

[0049] Pipe section A15, water pumps A57 and B58, pipe section B16, solenoid valve A28, pipe section C17, solenoid valve C30, pipe section G21, flow meter 36, pipe section H22, solenoid valve H35, pipe section J24, temperature sensor D40, refrigeration chamber 5, temperature sensor C39, temperature sensor B38, heating chamber 4, temperature sensor A37, pipe section I23, solenoid valve F33, pipe section H22 and pipe section K25 constitute the thermal regulation pipe 3 for refrigeration conditions under frequency domain analysis and constant power control.

[0050] Pipe section A15, water pumps A57 and B58, pipe section B16, solenoid valve B29, pipe section D18, water tank A26, pipe section E19, water tank B27, pipe section F20, solenoid valve D31, pipe section G21, flow meter 36, pipe section H22, solenoid valve E32, pipe section I23, temperature sensor A37, heating chamber 4, temperature sensor B38, temperature sensor C39, cooling chamber 5, temperature sensor D40, solenoid valve G34, pipe section H22, and pipe section K25 constitute the heat regulation pipe 3 for heating conditions under constant temperature control.

[0051] Pipe section A15, water pumps A57 and B58, pipe section B16, solenoid valve B29, pipe section D18, water tank A26, pipe section E19, water tank B27, pipe section F20, solenoid valve D31, pipe section G21, flow meter 36, pipe section H22, solenoid valve H35, pipe section J24, temperature sensor D40, refrigeration chamber 5, temperature sensor C39, temperature sensor B38, heating chamber 4, temperature sensor A37, pipe section I23, solenoid valve F33, pipe section H22, and pipe section K25 constitute the thermal regulating pipe 3 for constant temperature control in refrigeration conditions.

[0052] Furthermore, such as Figure 3 and Figure 7 As shown, the heating chamber 4 includes a heating chamber isolation shell 41, a heating chamber radiator 42 is installed at the top center of the heating chamber isolation shell 41, and multiple stacked heating components are installed inside the heating chamber isolation shell 41. The heating components include a heating plate 44 and a heat exchange plate 45 connected below the heating plate 44. Preferably, as Figure 7 The heating assembly shown has two sets.

[0053] Furthermore, such as Figure 3 and Figure 8 As shown, the cooling chamber 5 includes a cooling chamber isolation shell 47. A cooling chamber radiator 48 is installed at the top center of the cooling chamber isolation shell 47. Multiple symmetrical cooling components are installed inside the cooling chamber isolation shell 47. The cooling components include a cooling plate 49, a heat exchange plate 45 connected to the cold end of the cooling plate 49, and hot end heat dissipation fins 50 connected to the hot end of the cooling plate 49. Preferably, as... Figure 8 The refrigeration components shown are provided in two sets.

[0054] The heat exchange plates 45 in the heating chamber 4 and the cooling chamber 5 have the same structure. An S-shaped heat exchange channel 46 is provided in the heat exchange plate 45 to improve the heat exchange effect of the heating chamber 4 and the cooling chamber 5.

[0055] To achieve regulation and control of the thermal regulating tube 3, further, such as Figure 3 As shown, electrical component 6 includes a radiator 52, a power supply 53, a switching power supply 54, a relay 55, a water pump frequency converter 56, a frequency converter operation panel 59, a temperature controller 60, a PLC controller 61, and a display 62.

[0056] The power supply 53 is connected to the switching power supply 54, relay 55, water pump inverter 56, and water pump; the switching power supply 54 is connected to the temperature controller 60, PLC controller 61, display 62, and radiator 52; the inverter operation panel 59 is connected to the water pump inverter 56.

[0057] Furthermore, such as Figure 1As shown, the protective box 1 includes a protective box body 8. The two ends of the protective box body 8 are connected to the front cover 7 and the rear cover 9 of the protective box body 8 by protective box screws 10. The surface of the protective box body 8 has openings corresponding to the heating chamber 4, the cooling chamber 5, and the electrical components 6.

[0058] Furthermore, such as Figure 2 As shown, the test chassis 2 includes a test chassis body 11. A top cover 13 is connected to the top of the test chassis body 11 via chassis screws 14. Slide rails 12 for connecting the protective box 1 are provided on both sides of the test chassis body 11. The slide rails 12 allow the test chassis 2 to be easily pulled out of the protective box 1 when the front cover 7 or rear cover of the protective box is opened, facilitating inspection and maintenance. The test chassis 2 is equipped with a dustproof mesh 51 with corresponding heat dissipation properties, ensuring the cleanliness of the test chassis 2 and preventing dust from affecting the working performance of the electrical components 6.

[0059] A method for stratified testing of thermal property parameters, based on the aforementioned stratified testing instrument for thermal property parameters, includes the following steps:

[0060] S1: Install test heat exchange tubes in the selected underground energy structure area, setting the length of the installed heat exchange tubes to be... L .

[0061] S2: Use testing instruments to perform phase calibration on the heat exchanger tubes and fix the amplitude of the water supply temperature waveform. A 0 , A 0 You can choose the commonly used constant water supply temperature and initial soil temperature for the load-bearing buildings in the area. T soil The average value.

[0062] if t The frequency of water supply temperature fluctuations at any given time is f n At this time, the water supply temperature fluctuates. T in ( t )for: ;

[0063] With fluctuations in water supply temperature T in ( t Corresponding return water temperature fluctuation T out ( t )for: ;

[0064] in, B 0 The amplitude of the return water temperature waveform. f' n The frequency of return water temperature fluctuation, and the frequency of supply water temperature fluctuation.f n Different sizes ф n This represents the delayed phase of the return water temperature waveform. Since it takes time for the water to flow from the inlet to the outlet, the temperature fluctuation measured at the outlet will lag behind the inlet phase. However, the specific value of this phase lag has little impact on this invention, and therefore its precise magnitude can be ignored in testing.

[0065] If the frequency of water supply temperature fluctuations becomes f n+1 ,and f n > f n+1 At this time, the water supply temperature fluctuates. T in ( t )for: ;

[0066] With fluctuations in water supply temperature T in ( t Corresponding return water temperature fluctuation T out ( t )for: ;

[0067] in, f' n+1 The frequency of return water temperature fluctuations, compared to the frequency of supply water temperature fluctuations. f n+1 Different sizes.

[0068] If the above relationship is satisfied, then the critical frequency corresponding to the borehole is: ;

[0069] A critical frequency is obtained through phase calibration. f c This ensures that at this frequency, the measured return water temperature fluctuation just meets the threshold of 0.1℃, at which point the return water temperature fluctuation can be measured. The frequency of this supply water temperature fluctuation is the critical frequency of the supply water temperature fluctuation. f c .

[0070] S3: Use testing instruments to calibrate the amplitude of the heat exchanger tubes, fixing the frequency of the water supply temperature waveform as follows. f 0 , f 0 The critical frequency of water supply temperature fluctuation obtained in S2 is selected. f c Half of it.

[0071] ift The amplitude of the constant fluctuation in water supply temperature is A n At this time, the water supply temperature fluctuates. T in ( t )for: ;

[0072] With fluctuations in water supply temperature T in ( t Corresponding return water temperature fluctuation T out ( t )for: ;

[0073] in, f '0' represents the frequency of return water temperature fluctuations, which is different from the frequency of supply water temperature fluctuations. f 0 different sizes, B n This represents the amplitude of the return water temperature fluctuation.

[0074] If the amplitude of the water supply temperature fluctuation becomes A n+1 ,and A n+1 > A n At this time, the water supply temperature fluctuates. T in ( t )for: ;

[0075] With fluctuations in water supply temperature T in ( t Corresponding return water temperature fluctuation T out ( t )for: ;

[0076] in, B n+1 This represents the amplitude of the return water temperature fluctuation.

[0077] If the above relationship is satisfied, then the critical amplitude corresponding to the borehole is: ;

[0078] A critical amplitude is obtained through amplitude calibration. A c This ensures that, at this amplitude, the measured return water temperature fluctuation just meets the threshold of 0.1℃, at which point the return water temperature fluctuation can be measured. The amplitude of this supply water temperature fluctuation is the critical amplitude of the supply water temperature fluctuation. A c .

[0079] S4: Using a testing instrument in constant temperature control mode, the temperature in the heat exchange tube is restored to the initial soil temperature. T soil The measured temperatures of temperature sensors A (37), B (38), C (39), and D (40) are respectively... T 1 , T 2 , T 3 and T 4 The distances between two adjacent sensors are respectively... L 1 , L 2 and L 3 .

[0080] For heating conditions, if the testing instrument is started, T soil > T 1 ( t If the power of heating chamber 4 is set, then... Q h and the set power of cooling chamber 5 Q c as follows: ; ;

[0081] in, Q h ( t () represents the cooling power set at the current time step. Q h ( t +1) represents the cooling power to be set in the next time step. Q c ( t () represents the cooling power set at the current time step. Q c ( t +1) represents the cooling power to be set in the next time step. m The mass flow rate of water, c p This is the specific heat capacity of water.

[0082] For heating conditions, if the testing instrument is started, T soil = T 1 ( t ),but Qh and Q c for: ; ;

[0083] For heating conditions, if the testing instrument is started, T soil < T 1 ( t ),but Q h and Q c for: ; ;

[0084] For cooling operation, the relationship between temperature judgment and power change is the same as for heating operation; it is only necessary to change the measurement point from... T 1 Replace with T 4 .

[0085] S5: Test the heat exchange tubes using testing instruments. The frequency of water supply temperature fluctuation is the critical frequency of water supply temperature fluctuation. f c The amplitude of the water supply temperature fluctuation is the critical amplitude of the water supply temperature fluctuation. A c The specific form is as follows: ;

[0086] The return water temperature fluctuations monitored at the return water location during the first cycle. T out ( t )for: ;

[0087] in, A m The amplitude of the return water temperature fluctuation. ф m This is a delayed phase.

[0088] Determine the frequency of return water temperature fluctuations f m and the frequency of water supply temperature fluctuations f n The size relationship.

[0089] S6. Determine the current heat exchange tube length based on the judgment result of S5. L Is it appropriate?

[0090] if f m < f nThis indicates that the heat transfer performance of a smaller heat exchanger tube depth is much lower than that of a larger heat exchanger tube depth, and a new tube with a length of 2 is needed. L The heat exchange tubes were tested again starting from S1.

[0091] if f m ≈ f n This indicates that the heat transfer performance of a smaller heat exchanger tube depth is greater than or equal to that of a larger heat exchanger tube depth. In this case, the current heat exchanger tube length can be considered... L The requirements are met if the heat exchange tube length is... L The length is still relatively large, so it can be redeployed to a length of [missing information]. L The heat exchange tubes of / 2 were tested again starting from S1.

[0092] During the test, the heat exchange of the borehole under heating and cooling conditions was as follows: ; ;

[0093] in Q h For heat exchange under heating conditions, Q c This refers to the heat exchange during refrigeration.

[0094] Furthermore, the testing instrument in this invention also has a constant power control mode, the specific control principle of which is as follows:

[0095] For heating conditions, measurement T 1 , T 3 and T 4 Temperature data.

[0096] Equivalent heating power Q hd ( t )for: ;

[0097] in, ρ The density of the circulating water, cp The specific heat capacity of water, v The flow rate of the circulating water is measured by flow meter 36. A This is the flow cross-sectional area of ​​the heat exchange tube, that is, the cross-sectional area corresponding to the inner diameter of the heat exchange tube.

[0098] Circulating water from measuring point T 1 to the measuring point T 3 The flow time is: ;

[0099] Determine the heating power set in heating chamber 4 under constant power control. Q hset With equivalent heating power Q hd ( t The size relationship of ).

[0100] if Q hd ( t )> Q hset Then the set power of heating chamber 4 and cooling chamber 5 are changed to: ; ;

[0101] if Q hd ( t ) = Q hset Then the set power of heating chamber 4 and cooling chamber 5 are changed to: ; ;

[0102] if Q hd ( t )< Q hset Then the set power of heating chamber 4 and cooling chamber 5 are changed to: ; ;

[0103] For refrigeration operation, measurement T 1 , T 2 and T 4 Temperature data.

[0104] The equivalent cooling power is: ;

[0105] Circulating water from measuring point T 4 to the measuring point T 2 The flow time is: ;

[0106] Determine the set cooling power of cooling chamber 5 under constant power control. Q cset With equivalent cooling power Q cd ( t The size relationship of ).

[0107] if Q cd (t )> Q cset Then the set power of heating chamber 4 and cooling chamber 5 are changed to: ; ;

[0108] if Q cd ( t ) = Q cset Then the set power of heating chamber 4 and cooling chamber 5 are changed to: ; ;

[0109] if Q cd ( t )< Q cset Then the set power of heating chamber 4 and cooling chamber 5 are changed to: ; .

Claims

1. A method for testing thermal physical parameter layering, characterized in that, Includes the following steps: S1, laying the test heat exchange pipe in the selected underground structure area of the energy source, and setting the length of the laid heat exchange pipe as L ; S2, using test instrument on heat exchange tube phase calibration, get the critical frequency of water temperature fluctuation f c ; S3, using test instrument to heat exchange tube amplitude calibration, get the critical amplitude of water temperature fluctuation A c ; S4, in the constant temperature control mode, the temperature in the heat exchange pipe is restored to the initial temperature of the soil T soil ; S5, the critical frequency of water supply temperature fluctuation obtained according to S2 and S3 f c and the critical amplitude of water supply temperature fluctuation A c outputting a test water supply temperature fluctuation, and judging the size relationship between the frequency of return water temperature fluctuation and the critical frequency of water supply temperature fluctuation f c ​ S6, determining the current heat exchange tube length according to the result of S5 L whether it is appropriate, if not, then the heat exchange tube length needs to be changed L then reiterating from S1 The testing instrument includes a protective box (1), a testing chassis (2) is installed inside the protective box (1), and a heating chamber (4), a cooling chamber (5), a heat regulating pipe (3) and an electrical component (6) are installed inside the testing chassis (2). The heating chamber (4) and the cooling chamber (5) are connected through the heat regulating pipe (3), and the electrical component (6) is connected to control the heat regulating pipe (3). The heat regulation pipe (3) includes pipe section A (15) for connecting the water supply port on the test chamber (2) and pipe section K (25) for connecting the water return port on the test chamber (2). Pipe section A (15) connects to several water pumps set in parallel. The other end of the water pump is connected to solenoid valves A (28) and B (29) set in parallel through pipe section B (16). The other end of solenoid valve A (28) is connected to solenoid valve C (30). The other end of solenoid valve B (29) is connected to several water tanks in sequence and then connected to solenoid valve D (31). Solenoid valve C (30) and solenoid valve D (31) are connected to flow meter (36). The other end of flow meter (36) is connected to solenoid valve E (32) and solenoid valve H (35) set in parallel. Pipe section K (25) is connected to solenoid valves F (33) and G (34) in parallel. Solenoid valves E (32) and F (33) are connected to heating chamber (4) through temperature sensor A (37). Solenoid valves G (34) and H (35) are connected to cooling chamber (5) through temperature sensor D (40). Heating chamber (4) is connected to cooling chamber (5) in sequence through temperature sensor B (38) and temperature sensor C (39).

2. The method of claim 1, wherein, The heating chamber (4) includes a heating chamber isolation shell (41), and a heating chamber radiator (42) is installed at the top center of the heating chamber isolation shell (41).

3. The thermal property parameter layering test method of claim 2, wherein, The heating chamber is equipped with a multi-layer stacked heating assembly inside the heating chamber isolation shell (41). The heating assembly includes a heating plate (44) and a heat exchange plate (45) connected below the heating plate (44).

4. The method of claim 1, wherein, The cooling chamber (5) includes a cooling chamber isolation shell (47), and a cooling chamber radiator (48) is installed at the top center of the cooling chamber isolation shell (47).

5. The method of claim 4, wherein the thermal property parameter is a thermal conductivity. The refrigeration chamber is equipped with a multi-layer symmetrical refrigeration assembly inside the refrigeration chamber isolation shell (47). The refrigeration assembly includes a refrigeration plate (49), a heat exchange plate (45) connected to the cold end of the outer side of the refrigeration plate (49), and a heat dissipation fin (50) connected to the hot end of the inner side of the refrigeration plate (49).

6. The method for stratified testing of thermophysical parameters according to claim 1, characterized in that, The electrical components (6) include a radiator (52), a power supply (53), a switching power supply (54), a relay (55), a water pump frequency converter (56), a frequency converter operation panel (59), a temperature controller (60), a PLC controller (61), and a display (62). The power supply (53) is connected to the switching power supply (54), relay (55), water pump inverter (56), and water pump; the switching power supply (54) is connected to the temperature controller (60), PLC controller (61), display (62), and radiator (52); the inverter operation panel (59) is connected to the water pump inverter (56).

7. A method for stratified testing of thermophysical parameters according to any one of claims 1-6, characterized in that, The protective box (1) includes a protective box body (8). The two ends of the protective box body (8) are connected to the front cover (7) and the rear cover (9) of the protective box by protective box screws (10). The surface of the protective box body (8) has openings corresponding to the heating chamber (4), the cooling chamber (5) and the electrical components (6).

8. The method for stratified testing of thermophysical parameters according to claim 7, characterized in that, The test chassis (2) includes a test chassis body (11), and a chassis cover (13) is connected to the top of the test chassis body (11) by chassis screws (14). The test chassis body (11) has slide rails (12) on both sides for connecting the protective box (1).

Images