Energy loss measurement method for compressed air energy storage process based on force-thermal flow simulation test

Abstract

The present application relates to compressed air energy storage technology field, specifically disclose a kind of compressed air energy storage process energy loss measurement method based on force heat flow simulation test.The present application is under the guidance of force heat flow coupling similarity criterion dynamically collected cavern air pressure and temperature, and uses gas internal energy and heat change calculation formula to calculate the energy loss of gas storage stage, realize the energy loss of gas storage stage in simulation test process and analysis.The method of the present application not only greatly reduces the high capital investment and long time period of large-scale simulation test in traditional method, but also significantly improves the test efficiency and research feasibility, provides more scientific, accurate and reliable technical support for energy efficiency optimization of compressed air energy storage system.

Description

Technical Field

[0001] This invention relates to the field of compressed air energy storage technology, and in particular to a method for measuring energy loss in compressed air energy storage processes based on force-thermal-fluid simulation experiments. Background Technology

[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] As the global energy structure accelerates its transformation towards a green and low-carbon direction, the peak-shaving capacity of power grids faces unprecedented challenges. Against this backdrop, new power systems based on new energy sources have become a research focus, with compressed air energy storage power stations, as a large-scale energy storage technology, attracting significant attention. The underground spaces left by the mining of coal and other mineral resources in my country provide natural "air storage containers" for compressed air energy storage, possessing significant resource reuse value. For example, patent documents such as application numbers 202210065675.9, 202411954318.3, and 202411989165.6 have explored technologies for utilizing these abandoned mines for compressed air energy storage.

[0004] However, compressed gas storage in abandoned mines is a systems engineering project involving the coupling of multiple fields of mechanics, thermodynamics, and fluid dynamics, and it still faces many technical challenges. For example, the complexity and heterogeneity of the mine structure increase the risk of gas leakage, and the deformation of the surrounding rock under the coupling of multiple fields of force, heat, and fluid leads to a decrease in energy storage efficiency. Traditional compressed gas storage simulation tests mainly fall into two categories. One method uses numerical calculations and simulations to analyze the variation law of the gas storage chamber under cyclic alternating temperature and pressure loads. This method has significant deviations from the actual gas storage chamber due to factors such as model simplification or boundary condition assumptions. The other method is to construct a large-scale physical simulation test device for simulation. This method requires the development of similar materials for the confining pressure, lining, and sealing plugs of the simulated gas storage chamber. However, it is difficult for the developed similar materials to achieve complete similarity with the prototype medium, thus affecting the accuracy of the simulation results. In addition, large-scale simulation tests not only consume huge amounts of funds but also have long test cycles and cannot quantitatively characterize the heat dissipation during the simulated gas storage process. Summary of the Invention

[0005] This invention proposes a method for measuring energy loss in compressed air energy storage processes based on force-thermal-fluid simulation experiments. This method significantly improves the accuracy and reliability of simulation experiments, providing more scientific, accurate, and reliable technical support for optimizing the energy efficiency of compressed air energy storage systems. Specifically, the technical solution of this invention is as follows.

[0006] A method for measuring energy loss in a compressed gas energy storage process based on force-thermal-fluid simulation experiments, comprising the following steps:

[0007] (1) Determine the geometric similarity scale based on the actual dimensions of the proposed compressed air storage chamber. C l Then, based on the similarity criterion of force-thermal-fluid coupling in the compressed air energy storage process, the similarity scale of the remaining parameters is determined.

[0008] (2) Based on the similarity criterion, according to the end time of the compressed air filling in the proposed gas storage chamber. High-pressure gas storage end time point Time of venting end Low-pressure gas storage end time point Determine: the end time of inflation in the simulation test t 1 ′、Simulation test high-pressure gas storage end time point t 2 ′、Simulation test venting end time point t 3 ′、Simulation test low-pressure gas storage end time point t 4 ′.

[0009] (3) Based on the similarity criterion, according to the isotropic geostress of the strata at the location of the proposed compressed air storage chamber. Determine the isotropic axial pressure and confining pressure applied to the simulated gas storage chamber during the simulation test.

[0010] (4) According to step (1) C l Prepare the simulated test gas storage chamber, place it in the simulated test device, and initially maintain the gas pressure in the gas storage chamber at a certain level. P 0, 0~ t 1 The stage involves raising the air pressure to... P 1 The setting is to fill with the appropriate amount of gas. t 1 ′~ t 2 The stage maintains the inflated state. t 2 ′~ t 3 The stage involves reducing the air pressure to P 3 The setting releases a corresponding amount of gas. t 3 ′~ t 4A full-process simulation test of compressed gas energy storage was conducted, maintaining the state after the initial venting phase, and the data were collected. t 1 ′、 t 2 ′、 t 3 ′、 t 4 The actual gas pressure in the simulated gas storage chamber at time point ' P i ′ and temperature T i , i =1, 2, 3, 4. The above... P 0、 P 1 , P 3 This refers to the preset air pressure for the corresponding stage of operation of the actual proposed compressed air storage chamber.

[0011] (5) Calculate the above t 1 ′、 t 2 ′、 t 3 ′、 t 4 At time point ', the internal energy of the gas in the simulated gas storage chamber U i , i =1, 2, 3, 4, and then calculate the... t 1 ′~ t 2 Internal energy changes during the ′ stage t 3 ′~ t 4 Internal energy changes during the ′ stage t 1 ′~ t 2 Energy loss in the ' stage. Based on this, calculate the energy loss in the ' stage. t 1 ′~ t 2 Phase ': Total energy loss percentage η heat loss ratio η Q and the proportion of gas leakage losses η g This means obtaining the energy loss situation in the compressed air energy storage process.

[0012] Further, in step (1), the geometric similarity scale... C lThe dimensions can be determined based on the size of the simulation test apparatus so that the geometric similarity scale can be used. C l The prepared simulated gas storage chamber is installed in the simulated test apparatus. For example, it is obtained based on the dimensions of an existing simulated test apparatus. C l =50, which means the size of the actual proposed compressed air storage chamber is reduced by 50 times and used as the size of the simulated test storage chamber.

[0013] Furthermore, in step (1), the similarity scale of the remaining parameters based on the force-heat-fluid coupling similarity criterion is as follows: temperature similarity scale. =1. Pressure similarity scale =1. Stress similarity scale =1. Time similarity scale = C l 2 Gas thermal conductivity similarity ratio =1. Gas viscosity coefficient similarity ratio =1. Similarity ratio of specific heat capacity of gases =1. Gas density similarity scale =1. Similarity scale of gas mole numbers = C l 3 Surface heat transfer coefficient similarity scale =1. Solid Deformation Similarity Scale =1. Similarity ratio of solid elastic modulus =1. Solid permeability similarity scale =1. Solid porosity similarity scale =1. Thermal conductivity similarity scale =1. Similarity scale of specific heat capacity coefficient =1. Solid density similarity scale =1. Similarity scale of solid thermal expansion coefficient =1. Where: except for and The similarity scale for all other parameters is 1, meaning that it is only necessary to refer to the aforementioned time similarity scale. The duration of each stage in the depressurized gas energy storage process, and the similarity scale based on the number of moles of the gas. The simulation test can be conducted by reducing the amount of gas filled into the simulated test gas storage chamber, and the dynamic similarity between the simulation test and the actual project can be achieved.

[0014] Furthermore, in step (2), at each time point t i The calculation of ′ is performed using the following formula:t i ′= t i / C t , i =1, 2, 3, 4, Time similarity scale C t = C l 2 .

[0015] Furthermore, in step (3), the isotropic axial compression and confining compression The calculation formulas are all: , wherein: the The stress similarity scale is given.

[0016] Furthermore, in step (4), the simulation test device has the functions of applying triaxial stress loading to the simulation test gas storage chamber, filling the simulation test gas storage chamber with compressed gas at a constant speed, and monitoring and collecting the stress, temperature, and gas pressure.

[0017] Furthermore, in step (4), the amount of gas used for inflation... N' Calculate using the following formula: .in: The molar number similarity scale of the gas is given. N The proposed compressed air storage chamber is located at 0~ t 1 The amount of gas to be injected into it at each stage.

[0018] Further, in step (5), the... t 1 ′~ t 2 The formula for calculating the change in internal energy during the ′ stage is: △ U 2~1 = U 2- U 1. Among them: U 1 , U 2 All based on the formula calculate, i =1, 2, P i As shown in step (4), V This refers to the volume of the simulated gas storage chamber. C V This refers to the specific heat capacity at constant volume of the gas in the simulated gas storage chamber. R Refers to the ideal gas constant.

[0019] Further, in step (5), the... t 3 ′~ t 4 The formula for calculating the change in internal energy during the ′ stage is: △ U 4~3 = U 4- U 3, of which: U 3 , U 4 All based on the formula calculate, i =3, 4, P i As shown in step (4), V This refers to the volume of the simulated gas storage chamber. C V This refers to the specific heat capacity at constant volume of the gas in the gas storage chamber. R Refers to the ideal gas constant.

[0020] Further, in step (5), the... t 1 ′~ t 2 The formula for calculating heat loss in stage ′ is: .in: P 1 ′、 T 1 These refer to the data collected in step (4) above. t 1 Air pressure and temperature at a given time point; T 2 Refers to the data collected in step (4) above. t 2 Temperature at a given time point; V This refers to the volume of the simulated gas storage chamber. C V This refers to the specific heat capacity at constant volume of the gas in the gas storage chamber. R Refers to the ideal gas constant.

[0021] Furthermore, the volume of the simulated test gas storage chamber... V = V 1 / C l 3 .in: V 1 This refers to the volume of the proposed compressed air storage chamber mentioned in step (1). Alternatively, the volume can be directly calculated based on the dimensions of the simulated test storage chamber. V .

[0022] Furthermore, in step (5), the formula for calculating the proportion of total energy loss is: .

[0023] Furthermore, in step (5), the formula for calculating the proportion of heat loss is: .

[0024] Furthermore, in step (5), the formula for calculating the proportion of gas leakage loss is as follows: .

[0025] Compared with the prior art, the present invention has at least the following beneficial technical effects:

[0026] (1) This invention proposes a novel method for measuring energy loss in compressed air energy storage processes. To this end, this invention innovatively employs a force-thermal-fluid coupling similarity criterion applicable to compressed air energy storage processes, and then uses this criterion to determine the similarity scale of other parameters. This allows for simulation experiments to be conducted simply by scientifically reducing the duration of each stage in the gas compression energy storage process and the amount of gas injected into the simulated gas storage chamber, achieving dynamic similarity between the simulation experiment and actual engineering. This method not only significantly reduces the high cost and long timeframe of large-scale simulation experiments in traditional methods, but also significantly improves experimental efficiency and research feasibility.

[0027] (2) The method of this invention has significant versatility and adaptability, and can conduct experiments on different gas storage structures, new sealing materials, and new operating pressure conditions. Through innovative force-thermal-fluid coupling similarity criteria and scientific parameter scaling, it can accurately and efficiently obtain the energy dissipation of the gas storage chamber, thereby providing key data support for optimizing the design and operation of the gas storage system. In contrast, traditional large-scale simulation test methods are limited by high capital costs and long test cycles, making it difficult to quickly and accurately obtain relevant data under various new conditions. While numerical simulation methods can perform calculations quickly, the accuracy of their results is highly dependent on the rationality of the model and assumed boundary conditions, and the simulation process often differs significantly from the actual complex physical process, especially under complex operating conditions involving multi-physics coupling, where accuracy and reliability are often difficult to guarantee. The method proposed in this invention effectively compensates for the shortcomings of large-scale simulation tests and numerical simulations through the dynamic similarity between simulation tests and actual engineering. It can not only accurately measure the energy dissipation in the gas storage chamber, but also efficiently adapt to the test requirements of various new operating conditions, providing more scientific, accurate, and reliable technical support for the energy efficiency optimization of compressed gas energy storage systems. Attached Figure Description

[0028] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0029] Figure 1 The following is a schematic diagram of the structure of the gas storage chamber used for simulation testing in the embodiments below.

[0030] Figure 2 The following is a physical diagram of the gas storage chamber used for simulating the test in the embodiments below.

[0031] Figure 3 The following examples simulate the actual gas pressure in the test gas storage chamber. P i The test results.

[0032] Figure 4 The following examples simulate the actual temperature in the test gas storage chamber. T i The test results. Detailed Implementation

[0033] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0034] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0035] For ease of description, the words "up," "down," "left," and "right" appearing in this invention only indicate that they are consistent with the up, down, left, and right directions of the accompanying drawings themselves. They do not limit the structure and are merely for the purpose of facilitating the description of this invention and simplifying the description. They do not indicate or imply that the device or component referred to needs to have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0036] The energy loss measurement method for compressed gas energy storage based on force-thermal-fluid simulation experiments proposed in this invention will now be further described with reference to the accompanying drawings. Specifically, the measurement method includes the following steps:

[0037] (1) Set the geometric similarity scale C l =50, which means reducing the size of the actual proposed compressed air storage chamber by a factor of 50. Then, based on the dimensional parameters obtained after the reduction (such as... Figure 1The method for preparing a simulated gas storage chamber (as shown) is as follows: A rock identical to the proposed compressed air storage chamber is cut and processed using laser cutting technology to create the simulated gas storage chamber (as shown). Figure 2 (As shown). Then, temperature sensors are attached to the inner wall, and the two gas storage chambers are bonded together using polyurethane sealant. After curing, they form a single unit. (Reference) Figure 1 First, the chamber on the right side of the sealing plug is filled with a rubber plug. Then, sulfoaluminate cement-based sealing material (the same material as the sealing plug of the proposed compressed air storage chamber) is poured from the left side of the storage chamber to the location of the sealing plug and allowed to cure naturally for seven days. After curing, the rubber plug is removed, thus obtaining the storage chamber for simulation testing. In this embodiment, the left side chamber is used as the location for conducting ram gas energy storage tests (hereinafter referred to as the storage chamber, see reference). Figure 1 ).

[0038] (2) Based on the force-thermal-fluid coupling similarity criterion in compressed air energy storage, the similarity scale of the remaining parameters is determined, ensuring that the surrounding rock material, sealing material, compressed gas type, and gas pressure of the simulated gas storage chamber are consistent with those of the actual compressed air energy storage. In this case, the similarity scale of the remaining parameters based on the force-thermal-fluid coupling similarity criterion is: temperature similarity scale. =1. Pressure similarity scale =1. Stress similarity scale =1. Time similarity scale = C l 2 Gas thermal conductivity similarity ratio =1. Gas viscosity coefficient similarity ratio =1. Similarity ratio of specific heat capacity of gases =1. Gas density similarity scale =1. Similarity scale of gas mole numbers = C l 3 Surface heat transfer coefficient similarity scale =1. Solid Deformation Similarity Scale =1. Similarity ratio of solid elastic modulus =1. Solid permeability similarity scale =1. Solid porosity similarity scale =1. Thermal conductivity similarity scale =1. Similarity scale of specific heat capacity coefficient =1. Solid density similarity scale =1. Similarity scale of solid thermal expansion coefficient =1.

[0039] It can be seen that: in addition to the above and The similarity scale for all other parameters is 1, meaning that it is only necessary to refer to the aforementioned time similarity scale. The duration of each stage in the depressurized gas energy storage process, and the similarity scale based on the number of moles of the gas. The simulation test can be conducted by reducing the amount of gas filled into the simulated test gas storage chamber, and the simulation test can achieve dynamic similarity with the actual project. This effectively overcomes the problems of distortion compared with reality, high cost, and long time cycle of the traditional method of conducting simulation tests by making large-scale physical simulation test devices.

[0040] (3) Based on similarity criteria t i ′= t i / C t = t i / 2500, i =1, 2, 3, 4, Time similarity scale C t = C l 2 According to the proposed compressed air storage chamber, the inflation completion time point... t 1 High-pressure gas storage end time point Time of venting end Low-pressure gas storage end time point Determine: the end time of inflation in the simulation test t 1 ′、Simulation test high-pressure gas storage end time point t 2 ′、Simulation test venting end time point t 3 ′、Simulation test low-pressure gas storage end time point t 4 The results are shown in Table 1 below.

[0041] Table 1

[0042]

[0043] (4) Based on the similarity criterion, according to the isotropic geostress of the strata where the proposed gas storage chamber is located. =8MPa The isotropic axial pressure and confining pressure applied to the simulated gas storage chamber during the simulation test are determined. All are: Based on the gas molar number similarity ratio in step (2) above. =C l 3 Calculate 0~ t 1 The amount of gas introduced into the simulated test gas storage chamber during the 'stage' phase N' The calculation method is as follows: = N / C l 3 = N / 12500, N The proposed compressed air storage chamber is located at 0~ t 1 The amount of gas (air) to be introduced into it during the stage is 330725 mol, resulting in... N' =26.458 mol.

[0044] (5) The simulated gas storage chamber prepared in step (1) is placed vertically in the triaxial loading chamber / triaxial chamber 1-10 of the triaxial test module 1 of the "self-balancing coal and rock triaxial loading seepage and displacement instrument" (see patent document application number CN201910729553.3) (i.e., the device). Figure 3 (In the black area in the middle), begin the experiment after completion:

[0045] (i) First, using the universal testing machine 2-1 in the pressure loading module 2 of the "self-balancing triaxial loading seepage and displacement instrument for coal and rock", a constant isotropic axial pressure is applied to the simulated test gas storage chamber through the piston 1-8. Then, using the electric booster pump 2-5, oil injection port 2-6, and oil outlet 2-7, a constant isotropic confining pressure is applied to the outer wall of the simulated test gas storage chamber through the confining pressure chamber 1-11. .

[0046] (ii) Using the gas source 3-3 and pressure reducing valve 3-5 in the fluid injection module 3 of the "self-balancing triaxial loading seepage and displacement instrument for coal and rock", the gas pressure in the simulated test gas storage chamber is maintained at a certain level through the fluid outflow channel 1-6 in the self-balancing piston rod 1-1. P 0 (i.e., the air pressure at the initial time / time 0), then referring to Table 1 above, at 0~ t 1 During the 'phase' (i.e., 0~10.2s), the gas pressure in the gas storage chamber is adjusted according to the... P 0 Rise to P 1 The setting is to fill with the appropriate amount of air (the amount of gas is as described above). N' Then turn off the gas supply 3-3, in t 1 ′~t 2 During the initial stage (10.2~17.3s), the high-pressure gas storage state is maintained after inflation. Then, using the external tangent channels 1-7 of the "self-balancing triaxial loading seepage and displacement instrument for coal and rock", the flow is carried out according to the... t 2 ′~ t 3 During the 'phase' (i.e., 17.3~21.4s), the gas pressure in the gas storage chamber is reduced to... P 3 The set amount of gas is released. Then the external channels 1-7 are closed. t 3 ′~ t 4 The first phase (21.4~34.6s) maintains the low-pressure gas storage state after venting. This completes one cycle of the compressed gas energy storage process simulation experiment. The above... P 0、 P 1 , P 3 This refers to the preset air pressure at a corresponding stage during the operation of the actual proposed compressed air storage chamber.

[0047] In the above process, the first pressure sensor 4-3 in the data acquisition module 4 of the "self-balancing triaxial loading seepage and displacement instrument for coal and rock" and the temperature sensor set in the simulated test gas storage chamber are used to collect the data. t 1 ′、 t 2 ′、 t 3 ′、 t 4 At that time point, the actual gas pressure in the gas storage chamber P i ′ and temperature T i :

[0048] The actual air pressure P i The test results of ′ are as follows Figure 3 As shown, it displays the gas pressure in the simulated test gas storage chamber at the initial time / time 0. P 0 =0.460MPa=0.460×10 6 Pa. t 1 The actual gas pressure in the gas storage chamber at that time point P 1 =2.999MPa = 2.999 × 10 6 Pa. t2 The actual gas pressure in the gas storage chamber at that time point P 2 =2.752MPa = 2.752×10 6 Pa. t 3 The actual gas pressure in the gas storage chamber at that time point P 3 =0.412MPa = 0.412×10 6 Pa. t 4 The actual gas pressure in the gas storage chamber at that time point P 4 =0.413MPa = 0.413×10 6 Pa.

[0049] The actual temperature T i The test results are as follows Figure 4 As shown, it displays each time point. t i '(include t 1 ′、 t 2 ′、 t 3 ′、 t 4 The corresponding temperatures are as follows: T 1 =54.05℃=327.20K, T 2 =42.59℃=315.74K, T 3 =0.54℃=273.69K, T 4 =13.32℃=286.47K.

[0050] (6) Calculate the above t 1 ′、 t 2 ′、 t 3 ′、 t 4 At time point ', the internal energy of the gas in the simulated gas storage chamber U i Specifically, the internal energy is calculated using the following formula: , i =1, 2, 3, 4. Where: P i ′ represents the data collected in the previous step. t iThe air pressure at that point in time, R This refers to the ideal gas constant (valued at 8.314 J / (mol·K)). C V The specific heat capacity at constant volume (the heat capacity of air) of the gas in the simulated gas storage chamber. C V =2.5 R, R (referring to the ideal gas constant), the P i The unit is Pa. V The unit is m 3 . V The volume of the simulated test gas storage chamber is referred to as [the volume of the chamber]. V It can also be based on Figure 2 The dimensions of the simulated gas storage chamber (diameter d=30mm, length h=34mm) were calculated using the formula for calculating the volume of a cylinder: V =π×r 2 ×h=3.14×(15×10 -3 m) 2 ×(34×10 -3 m) = 2.4 × 10 -5 m 3 The calculation results are shown in Table 2 below.

[0051] Table 2

[0052]

[0053] Then use the formula △ U 2~1 = U 2- U 1. Calculate the above t 1 ′~ t 2 Internal energy change during the ′ stage △ U 2~1 =-14.82J (a negative value indicates a decrease in internal energy). This can be calculated using the formula Δ... U 4~3 = U 4- U 3. Calculate the above t 3 ′~ t 4 Internal energy change during the ′ stage △ U 4~3 =0.06J (a positive value indicates an increase in internal energy).

[0054] (7) Calculate the above t 1 ′~ t 2The heat loss in stage ' is calculated using the following formula: . P 1 ′、 T 1 These refer to the data collected in step (5) above. t 1 Air pressure and temperature at a given time point; T 2 Refers to the data collected in step (5) above. t 2 Temperature at a given time point; V This refers to the volume of the simulated gas storage chamber. R The ideal gas constant. C V The specific heat capacity at constant volume (the heat capacity of air) of the gas in the simulated gas storage chamber. C V =2.5 R, R (Refers to the ideal gas constant). Calculations yield:

[0055] .

[0056] In the formula, the P 1 The unit is Pa. V The unit is m 3 , R =8.314 J / (mol·K), T The temperature is the thermodynamic temperature (K).

[0057] (8) Calculate separately t 1 ′~ t 2 The proportion of total heat loss in the ′ stage η heat loss ratio η Q and the proportion of gas leakage losses η g , specifically:

[0058] (i) The percentage of total energy loss η The calculation formula is: Thus obtain .

[0059] (ii) The proportion of heat loss η Q The calculation formula is: Thus, we obtain .

[0060] (iii) The proportion of gas leakage loss η g The calculation formula is: Thus obtain .

[0061] The following conclusions can be drawn from the above calculation results: (1) In the high-pressure gas storage stage ( t 1 ′~ t 2 ′), because △ U 2~1 A negative value of -14.82 J indicates that there was energy loss in the compressed air within the gas storage chamber, caused by heat loss and gas leakage. η Q < η g This indicates that energy loss caused by gas leakage is greater. Therefore, in actual gas storage, it is necessary to improve the sealing of the gas storage chamber to reduce gas leakage, and at the same time, measures should be taken to reduce heat loss and reduce energy loss. (2) In the low-pressure gas storage stage ( t 3 ′~ t 4 ′), due to the change in internal energy Δ during this stage U 4~3 A positive value of 0.06J indicates that the internal energy of the compressed air increases during this stage. This is mainly due to convective heat transfer between the side wall of the higher-temperature storage chamber and the air in the lower-temperature storage chamber. Therefore, a heat exchange system needs to be added during the low-pressure storage stage to control the fluctuation of the air temperature after the release.

[0062] The aforementioned energy loss measurement method innovatively uses formulas for calculating changes in gas internal energy and heat to quantitatively calculate the energy and heat dissipation inside the gas storage chamber in the simulated gas storage stage, which greatly improves the calculation efficiency and accuracy, and provides more scientific and effective technical support for the energy efficiency optimization of compressed gas energy storage systems.

[0063] Finally, it should be noted that any modifications, equivalent substitutions, or improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention. Although specific embodiments of this invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of this invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of this invention are still within the scope of protection of this invention.

Claims

1. A method for measuring energy loss in compressed gas energy storage processes based on force-thermal-fluid simulation experiments, characterized in that, Includes the following steps: (1) Determine the geometric similarity scale based on the actual dimensions of the proposed compressed air storage chamber. C l Then, based on the similarity criterion of force-thermal-fluid coupling in the compressed air energy storage process, the similarity scale of the remaining parameters is determined; (2) Based on the similarity criterion, according to the end time of the compressed air filling in the proposed gas storage chamber. High-pressure gas storage end time point Time of venting end Low-pressure gas storage end time point Determine: the end time of inflation in the simulation test t 1 ′、Simulation test high-pressure gas storage end time point t 2 ′、Simulation test venting end time point t 3 ′、Simulation test low-pressure gas storage end time point t 4 ′; (3) Based on the similarity criterion, according to the isotropic geostress of the strata at the location of the proposed compressed air storage chamber. When determining the simulation test, the isotropic axial pressure and confining pressure applied to the simulated gas storage chamber are... ; (4) According to step (1) C l Prepare the simulated test gas storage chamber, place it in the simulated test device, and initially maintain the gas pressure in the gas storage chamber at a certain level. P 0, 0~ t 1 The stage is to raise the air pressure to P 1 The setting is to fill with the appropriate amount of gas. t 1 ′~ t 2 The stage maintains the inflated state. t 2 ′~ t 3 The stage involves reducing the air pressure to P 3 The setting releases a corresponding amount of gas. t 3 ′~ t 4 A full-process simulation test of compressed gas energy storage was conducted, maintaining the state after the initial venting phase, and the data were collected. t 1 ′、 t 2 ′、 t 3 ′、 t 4 The actual gas pressure in the simulated gas storage chamber at time point ' P i ′ and temperature T i , i =1, 2, 3, 4; the above P 0、 P 1 , P 3 This refers to the preset air pressure for the corresponding stage of operation of the actual proposed compressed air storage chamber; (5) Calculate the above t 1 ′、 t 2 ′、 t 3 ′、 t 4 At time point ', the internal energy of the gas in the simulated gas storage chamber U i , i =1, 2, 3, 4, and then calculate the... t 1 ′~ t 2 Internal energy changes during the ′ stage t 3 ′~ t 4 Internal energy changes during the ′ stage t 1 ′~ t 2 Energy loss at stage '; based on this, calculate the energy loss at stage '. t 1 ′~ t 2 Phase ': Total energy loss percentage η heat loss ratio η Q and the proportion of gas leakage losses η g This means obtaining the energy loss situation in the compressed air energy storage process.

2. The method for measuring energy loss in compressed gas energy storage based on force-thermal-fluid simulation experiments according to claim 1, characterized in that, In step (1), the similarity scale of the remaining parameters based on the force-thermal-fluid coupling similarity criterion is as follows: temperature similarity scale. =1. Pressure similarity scale =1. Stress similarity scale =1. Time similarity scale = C l 2 Gas thermal conductivity similarity ratio =1. Gas viscosity coefficient similarity ratio =1. Similarity ratio of specific heat capacity of gases =1. Gas density similarity scale =1. Similarity scale of gas mole numbers = C l 3 Surface heat transfer coefficient similarity scale =1. Solid Deformation Similarity Scale =1. Similarity ratio of solid elastic modulus =1. Solid permeability similarity scale =1. Solid porosity similarity scale =1. Thermal conductivity similarity scale =1. Similarity scale of specific heat capacity coefficient =1. Solid density similarity scale =1. Similarity scale of solid thermal expansion coefficient =1.

3. The method for measuring energy loss in compressed gas energy storage based on force-thermal-fluid simulation experiments according to claim 1, characterized in that, In step (2), at each time point t i The calculation of ′ is performed using the following formula: t i ′= t i / C t , i =1, 2, 3, 4, Time similarity scale C t = C l 2 .

4. The method for measuring energy loss in compressed gas energy storage based on force-thermal-fluid simulation experiments according to claim 1, characterized in that, In step (3), the isotropic axial compression and confining compression The calculation formulas are all: , wherein: the The stress similarity scale is given.

5. The method for measuring energy loss in compressed gas energy storage based on force-thermal-fluid simulation experiments according to claim 2, characterized in that, In step (4), the amount of gas used for inflation... N' Calculate using the following formula: ;in: The molar number similarity scale of the gas is given. N The proposed compressed air storage chamber is located at 0~ t 1 The amount of gas to be injected into it at each stage; Alternatively, in step (4), the simulation test device has the functions of applying triaxial stress loading to the simulation test gas storage chamber, filling the simulation test gas storage chamber with compressed gas at a constant speed, and monitoring and collecting the stress, temperature, and gas pressure.

6. The method for measuring energy loss in compressed gas energy storage based on force-thermal-fluid simulation experiments according to claim 1, characterized in that, In step (5), the t 1 ′~ t 2 The formula for calculating the change in internal energy during the ′ stage is: △ U 2~1 = U 2- U 1; in: U 1 , U 2 All based on the formula calculate, i =1, 2, P i As shown in step (4), V This refers to the volume of the simulated gas storage chamber. C V This refers to the specific heat capacity at constant volume of the gas in the simulated gas storage chamber. R The ideal gas constant; Alternatively, in step (5), the... t 3 ′~ t 4 The formula for calculating the change in internal energy during the ′ stage is: △ U 4~3 = U 4- U 3, of which: U 3 , U 4 All based on the formula calculate, i =3, 4, P i As shown in step (4), V This refers to the volume of the simulated gas storage chamber. C V This refers to the specific heat capacity at constant volume of the gas in the gas storage chamber. R Refers to the ideal gas constant.

7. The method for measuring energy loss in compressed gas energy storage based on force-thermal-fluid simulation experiments according to claim 6, characterized in that, In step (5), the t 1 ′~ t 2 The formula for calculating heat loss in stage ′ is: ; in: P 1 ′、 T 1 These refer to the data collected in step (4) above. t 1 Air pressure and temperature at a given time point; T 2 Refers to the data collected in step (4) above. t 2 Temperature at a given time point; V This refers to the volume of the simulated gas storage chamber. C V This refers to the specific heat capacity at constant volume of the gas in the gas storage chamber. R Refers to the ideal gas constant.

8. The method for measuring energy loss in compressed gas energy storage process based on force-thermal-fluid simulation experiment according to claim 6 or 7, characterized in that, The volume of the simulated gas storage chamber V = V 1 / C l 3 ;in: V 1 The volume of the proposed compressed air storage chamber mentioned in step (1) can be used as a reference; or, the volume can be directly calculated based on the dimensions of the simulated test storage chamber. V .

9. The method for measuring energy loss in compressed gas energy storage based on force-thermal-fluid simulation experiments according to claim 6, characterized in that, In step (5), the formula for calculating the proportion of total energy loss is: .

10. The method for measuring energy loss in compressed gas energy storage process based on force-thermal-fluid simulation experiment according to claim 7, characterized in that, In step (5), the formula for calculating the heat loss ratio is: ; Alternatively, in step (5), the formula for calculating the proportion of gas leakage loss is: .

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