CN109142680B - Coal rock cleat compression coefficient testing device, determining method and system - Google Patents
Coal rock cleat compression coefficient testing device, determining method and system Download PDFInfo
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- CN109142680B CN109142680B CN201810946534.1A CN201810946534A CN109142680B CN 109142680 B CN109142680 B CN 109142680B CN 201810946534 A CN201810946534 A CN 201810946534A CN 109142680 B CN109142680 B CN 109142680B
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- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
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- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
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Abstract
The invention provides a coal rock cleat compression coefficient testing device, a determining method and a system, wherein the device comprises: the device comprises a pulse generator, an upstream gas bin, a rock core holder, a temperature controller, a temperature control box, a downstream gas bin, a helium tank and a constant flow pump; the outlet of the pulse generator is connected to the inlet of the core holder through an upstream gas bin, the outlet of one end of the downstream gas bin is connected with the outlet of the core holder, the outlet of the other end of the downstream gas bin is connected with an outlet stop valve, the advection pump is connected with the outer bin of the core holder through a high-pressure pipeline, the outlet of the pulse generator is further connected to the outlet of the other end of the downstream gas bin through a pipeline, the core holder is arranged in a temperature control box, a temperature controller is connected with the temperature control box to control the temperature of the temperature control box, and a helium tank is connected to the inlet of the pulse generator through a. The method realizes the test of the coal rock cleat compression coefficient under different conditions, reduces the experimental test time, establishes an accurate cleat compression coefficient calculation model, and improves the test precision.
Description
Technical Field
The invention relates to the technical field of coal rock experimental analysis in coal bed methane development, in particular to a coal rock cleat compression coefficient testing device, a coal rock cleat compression coefficient determining method and a coal rock cleat compression coefficient determining system.
Background
Along with the upgrade of domestic energy structures and the improvement of environmental requirements, the proportion of natural gas consumption in energy consumption is increased year by year, China is a country with abundant coal resources and relatively short natural gas resources, the coal bed methane industry can fully excavate natural gas resources, improve the utilization rate of non-renewable resources, reduce the safety accident rate of gas leakage, gas explosion and the like in the coal mining process, and is a new and unconventional energy industry which is greatly supported by the nation at present. Coal rock is a double-pore medium with extremely strong stress sensitivity, the cleat compression coefficient is one of key factors for determining the strength of the stress sensitivity, and the accurate control of the cleat compression coefficient of the coal rock is of great significance for making a coal bed gas well drainage scheme in a differentiation mode and scientifically compiling a coal bed gas field development scheme.
The development of the coal bed gas in China has a history of more than ten years, the research on the basic theory of the exploration and development of the coal bed gas is relatively weak due to late starting and short development time, particularly, the research on the coal rock property is not deep enough, and an indoor experiment is the most direct means for mastering the coal rock property, but due to the lack of an experimental device and a test method aiming at the characteristics of the coal rock, the method cannot play a due guiding role in the production and development of the coal bed gas.
In the prior art, no test standard about the coal rock cleat rock coefficient exists, the mathematical relationship between the coal rock permeability change rule and the cleat compression coefficient under different effective surrounding pressures is established based on a coal rock matchstick model in the prior art, and a cleat compression coefficient test method is provided, and the method in the prior art has the following problems: 1. the change of the cleat width caused by the elastic deformation of the coal rock matrix is not considered in the model, so that the theoretical model is not accurate enough; 2. the permeability is measured by adopting a steady state method to change along with the effective confining pressure, and because the permeability of the coal bed of the domestic coal gas field is less than 0.1mD (the permeability is generally lower than 2-3 orders of magnitude abroad), the time for the fluid to reach a steady flow state in the experimental process is long, and the error of flow measurement is large; 3. the influence of different forward and reverse flow directions on the coal rock cutting compression coefficient cannot be researched during the experiment, the experiment conditions are difficult to ensure to be completely consistent by artificially changing the direction of the rock core, and the experiment error is easy to increase; 4. the influence of different temperatures on the coal-rock cleat compression coefficient cannot be simulated.
Disclosure of Invention
In order to solve the problems existing in the coal rock cleat compression coefficient test and shorten the test time of the cleat compression coefficient, the embodiment of the invention provides a coal rock cleat compression coefficient test device, which comprises: the device comprises a pulse generator, an upstream gas bin, a rock core holder, a temperature controller, a temperature control box, a downstream gas bin, a helium tank and a constant flow pump; wherein the content of the first and second substances,
the outlet of the pulse generator is connected to the inlet of the core holder through an upstream gas bin, the outlet of one end of the downstream gas bin is connected with the outlet of the core holder, the outlet of the other end of the downstream gas bin is connected with an outlet stop valve, the advection pump is connected with the outer bin of the core holder through a high-pressure pipeline, the outlet of the pulse generator is further connected to the outlet of the other end of the downstream gas bin through a pipeline, the core holder is arranged in a temperature control box, a temperature controller is connected with the temperature control box to control the temperature of the temperature control box, and a helium tank is connected to the inlet of the pulse generator through a helium stop valve.
In the embodiment of the present invention, the device for testing the coal petrography cleat compression coefficient further includes: a confining pressure sensor, an upstream pressure sensor and a downstream pressure sensor;
the upstream pressure sensor is connected to the upstream pressure bin, the downstream pressure sensor is connected to the downstream pressure bin, and the confining pressure sensor is arranged between the advection pump and the outer bin of the core holder.
In the embodiment of the present invention, the device for testing the coal petrography cleat compression coefficient further includes:
the pulse generator stop valve is arranged between the pulse generator and the upstream gas bin;
the upstream pressure stop valve is arranged between the upstream gas bin and the core holder;
the downstream pressure stop valve is arranged between the rock core holder and the downstream gas bin;
the confining pressure stop valve is arranged between the confining pressure sensor and the constant flow pump;
and the bypass stop valve is arranged on pipelines of the outlet of the pulse generator and the outlet of the other end of the downstream gas bin.
Meanwhile, the invention also provides a method for determining the coal rock cleat compression coefficient, which is used for determining the coal rock cleat compression coefficient by using the testing device and comprises the following steps:
determining the porosity, the elastic modulus and the Poisson ratio of the coal rock of the rock sample under the initial confining pressure;
applying different confining pressures to the rock sample to provide pressure difference, and determining the slope relation between the dimensionless logarithm of the pressure difference and time and the average pore pressure under different confining pressures;
and determining the cleat compression coefficient according to the slope relation between the dimensionless pressure difference logarithm and time, the coal-rock porosity, the elastic modulus, the Poisson ratio, the average pore pressure under different confining pressures and a pre-established cleat compression coefficient model.
In an embodiment of the present invention, the providing a pressure difference for a rock sample, and determining a slope relationship between a dimensionless logarithm of the pressure difference and time includes:
providing pressure difference for the rock sample, and acquiring upstream gas bin pressure data and downstream gas bin pressure data at different moments;
determining a dimensionless pressure difference according to the upstream gas bin pressure data, the downstream gas bin pressure data and the following formula at different moments;
wherein, Δ pD(t) is the dimensionless pressure differential at time t; p is a radical of1(t) is the upstream gas bin pressure at time t; p is a radical of2(t) is the downstream gas bin pressure at time t; p is a radical of1(0) The pressure of the upstream gas bin at the initial moment; p is a radical of2(0) Is the initial time downstream gas bin pressure; Δ p (t) is the pressure difference between the upstream and downstream gas bins at time t; delta p (0) is the pressure difference between the upstream gas bin and the downstream gas bin at 0 moment;
determining the slope of the logarithm of the dimensionless pressure difference and the time according to the dimensionless pressure difference and the following formula;
wherein m is the slope of the dimensionless logarithm of the differential pressure with time; n is the number of counting points; t is tnTime for the nth calculation point; t is tn-1Time for the n-1 st calculation point; Δ p (t)n) Is tnThe pressure difference of the upstream and downstream gas bins at the moment; Δ p (t)n-1) Is tn-1The pressure difference of the upstream and downstream gas bins at the moment; p is a radical of2(tn) Is tnThe downstream gas bin pressure at time; p is a radical of2(tn-1) Is tn-1The time downstream gas bin pressure.
In the embodiment of the invention, when different confining pressures are applied to the rock sample, 1 MPa-2 MPa is increased every time, the variation of the confining pressure is not less than 5 groups, and the maximum value of the confining pressure is not more than 20 MPa.
In the embodiment of the present invention, the pre-established cleat compression coefficient model is:
wherein, CfA cleat compression factor; e is the elastic modulus of coal rock; nu is the Poisson ratio of the coal rock; phi is a0Coal rock porosity at initial confining pressure; delta PeThe difference between the coal rock ambient pressure and the initial ambient pressure is obtained, and the slope of the dimensionless logarithm of the differential pressure and the time is m; pm0The average pore pressure at the initial confining pressure; pmThe average pore pressure at different confining pressures.
Further, the invention also provides a system for determining the coal rock cleat compression coefficient, which comprises: the device comprises a coal-rock cleat compression coefficient testing device and a coal-rock cleat compression coefficient determining device;
coal petrography cleat compression coefficient testing arrangement, include: the device comprises a pulse generator, an upstream gas bin, a rock core holder, a temperature controller, a temperature control box, a downstream gas bin, a helium tank and a constant flow pump; wherein the content of the first and second substances,
an outlet of the pulse generator is connected to an inlet of the core holder through an upstream gas bin, an outlet of one end of the downstream gas bin is connected with an outlet of the core holder, an outlet of the other end of the downstream gas bin is connected with an outlet stop valve, a constant-flow pump is connected with an outer bin of the core holder through a high-pressure pipeline, an outlet of the pulse generator is also connected to an outlet of the other end of the downstream gas bin through a pipeline, the core holder is arranged in a temperature control box, a temperature controller is connected with the temperature control box to control the temperature of the temperature control box, and a helium tank is connected to an inlet of the pulse generator through a helium stop valve;
the coal rock cleat compression coefficient determining device comprises:
the initial parameter acquisition module is used for acquiring the porosity, the elastic modulus and the Poisson ratio of the coal rock of the rock sample under the initial confining pressure;
the pressure parameter determination module is used for applying pressure differences provided by different confining pressures to the rock sample and determining the slope relation between the dimensionless logarithm of the pressure difference and time and the average pore pressure under different confining pressures;
and the cleat compression coefficient determining module is used for determining the cleat compression coefficient according to the slope relation between the dimensionless pressure difference logarithm and time, the coal rock porosity, the elastic modulus, the Poisson ratio, the average pore pressure under different confining pressures and a pre-established cleat compression coefficient model.
In an embodiment of the present invention, the pressure parameter determining module includes:
the gas bin pressure acquisition unit is used for acquiring upstream gas bin pressure data and downstream gas bin pressure data at different moments when pressure difference is provided for the rock sample;
the dimensionless pressure difference determining unit is used for determining the dimensionless pressure difference according to the upstream gas bin pressure data, the downstream gas bin pressure data and the following formula at different moments;
wherein, Δ pD(t) is the dimensionless pressure differential at time t; p is a radical of1(t) is the upstream gas bin pressure at time t; p is a radical of2(t) is the downstream gas bin pressure at time t; p is a radical of1(0) The pressure of the upstream gas bin at the initial moment; p is a radical of2(0) Is the initial time downstream gas bin pressure; Δ p (t) is the pressure difference between the upstream and downstream gas bins at time t; delta p (0) is the pressure difference between the upstream gas bin and the downstream gas bin at 0 moment;
determining the slope of the logarithm of the dimensionless pressure difference and the time according to the dimensionless pressure difference and the following formula;
wherein m is the slope of the dimensionless logarithm of the differential pressure with time; n is the number of counting points; t is tnTime for the nth calculation point; t is tn-1Time for the n-1 st calculation point; Δ p (t)n) Is tnThe pressure difference of the upstream and downstream gas bins at the moment; Δ p (t)n-1) Is tn-1The pressure difference of the upstream and downstream gas bins at the moment; p is a radical of2(tn) Is tnThe downstream gas bin pressure at time; p is a radical of2(tn-1) Is tn-1The time downstream gas bin pressure.
The invention also provides a computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the method when executing the computer program.
The present invention also provides a computer-readable storage medium storing a computer program for executing the above method.
The device provided by the invention is additionally provided with the temperature control module and the bypass pipeline, so that the coal rock cleat compression coefficient test at different temperatures, different gas flow directions and different loading paths is realized, the experimental test time is greatly reduced based on the unsteady state method of pressure pulse attenuation, the influence of elastic deformation of the matrix on the cleat width is considered, a more accurate cleat compression coefficient calculation model is established, and the test precision is improved.
In order to make the aforementioned and other objects, features and advantages of the invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic diagram of an embodiment of a coal-rock cleat compression coefficient testing apparatus according to the present invention;
FIG. 2 is a flowchart of a method for determining a coal-rock cleat compression coefficient according to an embodiment of the present invention;
FIG. 3 is a flow chart of a method for testing the coal petrography cleat compression coefficient disclosed in the embodiment of the present invention;
FIG. 4 is a rule of variation of a non-dimensional ratio of permeability with effective confining pressure in an embodiment of the present invention;
FIG. 5 is a rule that the coal petrography cleat compression coefficient changes with the effective confining pressure in the embodiment of the present invention;
FIG. 6 is a block diagram of a coal petrography cleat compression factor determining apparatus according to an embodiment of the present disclosure;
FIG. 7 is a block diagram of a coal petrography cleat compression factor determining apparatus according to an embodiment of the present disclosure;
fig. 8 is a schematic block diagram of a system configuration according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention discloses a coal rock cleat compression coefficient testing device, which comprises: the device comprises a pulse generator, an upstream gas bin, a rock core holder, a temperature controller, a temperature control box, a downstream gas bin, a helium tank and a constant flow pump;
the outlet of the pulse generator is connected to the inlet of the core holder through an upstream gas bin, the outlet of one end of the downstream gas bin is connected with the outlet of the core holder, the outlet of the other end of the downstream gas bin is connected with an outlet stop valve, the advection pump is connected with the outer bin of the core holder through a high-pressure pipeline, the outlet of the pulse generator is further connected to the outlet of the other end of the downstream gas bin through a pipeline, the core holder is arranged in a temperature control box, a temperature controller is connected with the temperature control box to control the temperature of the temperature control box, and a helium tank is connected to the inlet of the pulse generator through a helium.
As shown in fig. 1, which is a schematic diagram of an embodiment of a coal-rock cleat compression coefficient testing apparatus according to the present invention, the coal-rock cleat compression coefficient testing apparatus disclosed in this embodiment includes: helium tank 101, pulser 102, variable volume upstream gas box 103, temperature control system 104, core holder 105, advection pump 106, variable volume downstream gas box 107, upstream pressure sensor PuConfining pressure sensor PcDownstream pressure sensor PdHelium tank stop valve V0Pulse generator stop valve V1Upstream pressure stop valve V2Confining pressure stop valve V3Downstream pressure stop valve V4Outlet stop valve V5Bypass line stop valve V6Bypass line stop valve V7Bypass line stop valve V8Reverse outlet stop valve V9And high-pressure sealing pipelines for connecting the experimental devices.
The upstream gas bin 103 and the downstream gas bin 107 are symmetrical in the testing process, when the volume ratio of the rock sample pore space to the volume ratio of the upstream gas bin 107 to the downstream gas bin 107 is 0.25-0.5, the error is minimum, and the volume of the gas bins can be adjusted according to the measured rock sample pore space volume.
The helium tank 101 is connected to a stop valve V of the helium tank by a high pressure sealed line0Helium tank stop valve V0The outlet of the pulse generator 102 is connected with a pulse generator through a high-pressure sealing pipeline, and the outlet of the pulse generator is connected with a pulse generator stop valve V through a high-pressure sealing pipeline1An upstream pressure sensor P connected to the upstream gas bin 102uConnected to an upstream gas bin 103, wherein the outlet of the upstream gas bin 103 is connected with an upstream pressure stop valve V through a high-pressure sealing pipeline2Connected, upstream pressure stop valve V2Is connected to the core holder inlet. The core holder 105 was placed in an incubator 108, and the incubator 108 adjusted the experimental temperature via the temperature control system 104. The constant flow pump 106 is connected with the confining pressure stop valve V through a high-pressure sealing pipeline3And confining pressure sensor PcConfining pressure sensor PcThe outer chamber of the core holder 105 was connected by a high pressure seal line. The outlet of the core holder 105 is connected with a downstream pressure stop valve V through a high-pressure sealing pipeline4Downstream gas cabin, downstream pressure sensor PdIs connected to the downstream gas bin 107, and the outlet at the right end of the downstream gas bin 107 is connected with an outlet stop valve V5Said outlet stop valve V5The right end is placed in the atmosphere. Bypass line slave pulser 102 and pulser shut-off valve V1Is connected out through a bypass pipeline stop valve V6Bypass line stop valve V7Bypass line stop valve V8Connected to the downstream gas bin 107 and outlet shut-off valve V5In the meantime.
According to the coal rock cleat coefficient testing device provided by the invention, the coal rock cleat compression coefficient tests at different temperatures, different gas flowing directions and different loading paths are realized through the temperature control module and the bypass pipeline, and the testing device is simple and practical.
Meanwhile, the invention also provides a method for determining the coal-rock cleat compression coefficient, which is used for determining the coal-rock cleat compression coefficient by using the coal-rock cleat coefficient testing device, and as shown in fig. 2, the method comprises the following steps:
step S201, determining the porosity, the elastic modulus and the Poisson ratio of the coal rock of the rock sample under the initial confining pressure;
step S202, applying different confining pressures to the rock sample to provide pressure difference, and determining the slope relation between the dimensionless logarithm of the pressure difference and time and the average pore pressure under different confining pressures;
step S203, determining a cleat compression coefficient according to the slope relation between the dimensionless pressure difference logarithm and time, the coal rock porosity, the elastic modulus, the Poisson ratio, the average pore pressure under different confining pressures and a pre-established cleat compression coefficient model.
The coal rock cleat compression coefficient determining method provided by the invention is based on the unsteady state method of pressure pulse attenuation, so that the experimental test time is greatly reduced; the influence of the elastic deformation of the matrix on the cleat width is considered, a more accurate cleat compression coefficient calculation model is established, and the test precision is improved. The process of the present invention is further illustrated in detail below with reference to specific examples.
Fig. 3 is a flowchart illustrating a method for testing a coal-rock cleat compression coefficient according to an embodiment of the present invention.
Step S301, obtaining the porosity, the elastic modulus and the Poisson ratio of the coal rock under the initial confining pressure state.
(1) And drilling the coal rock into a cylinder with the diameter not less than 5cm and the height 2-2.5 times of the diameter by using a coring bit. The diameter error of the rock sample is not more than 0.3mm, the non-parallelism of two end faces is not more than 0.05mm to the maximum extent, the end faces are perpendicular to the axis of the test piece, the maximum deviation is not more than 0.25 degrees, and no artificial crack is allowed to appear in the preparation process of the rock sample.
(2) And (3) wrapping the drilled rock sample with a polyethylene film, and drying the rock sample in a thermostat at 90 ℃ for 4h to remove the influence of moisture on the test.
(3) The porosity of the coal rock at an initial confining pressure (the initial confining pressure is less than 2MPa) was measured using an automatic CMS type core analyzer according to the requirements specified in the method for measuring porosity and permeability of rock under overburden pressure (SY/T6385-. Using an equal lateral pressure triaxial compression tester, according to the method for measuring physical and mechanical properties of coal and rock, part 9: the method for measuring the triaxial strength and deformation parameters of coal and rock (GB/T23561.9-2009) requires to measure the elastic modulus and Poisson's ratio of coal and rock.
Step S302, obtaining slope values of the dimensionless logarithm of pressure difference and time change relation of the coal rock under different ambient pressures, and determining dimensionless specific values of the coal rock permeability under different ambient pressures based on a pressure pulse attenuation method.
Assuming that the pore pressure of the initial rock sample is evenly distributed, when t is 0, a pressure pulse delta P (0) is applied to the rock sample inlet end through the upstream gas bin, the pressure in the upstream gas bin is reduced after the gas enters the rock sample, the pressure in the downstream gas bin keeps an initial value before the pressure pulse completely passes through the rock sample, the pressure in the upstream gas bin is gradually reduced along with the time after the pressure pulse passes through the rock sample, the pressure in the downstream gas bin is gradually increased along with the time, and the pressure difference between the upstream gas bin and the downstream gas bin is continuously reduced. The rate of decay of the pressure difference is dependent on the permeability, the lower the permeability, the slower the decay. A mathematical relation between the pressure difference attenuation speed and the permeability is established, and the dimensionless ratio of the permeability of the coal rock under different ambient pressures is determined by measuring the pressure difference attenuation speed of the rock sample under different ambient pressures, so that the method is particularly suitable for testing the coal rock cleat compression coefficient with the permeability lower than 0.1 mD.
The concrete operation steps for testing the coal rock cleat compression coefficient in one embodiment of the invention are as follows:
(1) the thermostat temperature was set to the experimental temperature by a temperature control system, ensuring that the temperature did not change within 30 minutes.
(2) The test rock sample is placed in a rubber sleeve in the rock core holder, gaskets with openings are placed at two ends of the rock sample, the rock sample is fixed, and gas is ensured to only seep along the axial direction of the rock sample.
(3) Opening confining pressure stop valve V3Then slowly applying confining pressure to an initial value through a constant flow pump, in the embodiment of the invention, the suggested pressure is not more than 2MPa, and a stop valve V of a helium tank is opened0Pulse generator stop valve V1Upstream pressure stop valve V2Downstream pressure stop valve V4Outlet stop valve V5Then use helium to wash the experimental apparatus, adjust the upper reaches pressure stop valve V2An initial equilibrium helium pressure of 9MPa (1300Psi) was ensured.
(4) Quick closing upstream pressure stop valve V2The pressure value of the upstream gas bin is increased to 9.2MPa through the pulse generator, and the downstream pressure sensor P is not allowed in the pressure increasing processdThe reading of (a) changes.
(5) Quick opening upstream pressure stop valve V2While recording the upstream pressure sensor PuDownstream pressure sensor PdThe value changes along with the time until the pressures of the upstream and downstream gas bins are re-balanced. The initial pressure change is fast, the recording time interval is small, and when the pressures of the gas bins on the two sides are balanced, the time interval for recording data can be properly increased.
In the embodiment of the invention, the dimensionless pressure difference calculation formula is as follows:
in the formula,. DELTA.pD(t) is the dimensionless pressure differential at time t; p is a radical of1(t) is the upstream gas bin pressure at time t, in MPa; p is a radical of2(t) is the downstream gas bin pressure at time t, in MPa; p is a radical of1(0) The pressure of an upstream gas bin at the initial moment is unit MPa; p is a radical of2(0) The pressure of a downstream gas bin at the initial moment is unit MPa; Δ p (t) is the pressure difference between the upstream and downstream gas bins at time t, in MPa; delta p (0) is the pressure difference of the upstream and downstream gas bins at 0 time, and the unit is MPa.
Wherein m is the dimensionless logarithm of differential pressure ln [ Δ p ]D(t)]The slope of the curve with time t; n is the number of counting points; t is tnTime of the nth calculation point is in unit of s; t is tn-1Time of the n-1 th calculation point is s; Δ p (t)n) Is tnThe pressure difference of the upstream and downstream gas bins at the moment is MPa; Δ p (t)n-1) Is tn-1The pressure difference of the upstream and downstream gas bins at the moment is MPa; p is a radical of2(tn) Is tnThe pressure of a downstream gas bin at the moment is MPa; p is a radical of2(tn-1) Is tn-1The pressure of the gas bin at the downstream of the moment is in MPa.
In the present embodiment, the gas is defined to be in a forward direction from the upstream gas bin to the downstream gas bin, and vice versa. The coal rock cleat coefficient testing device disclosed in the embodiment of the invention can be used for researching the influence of different forward and reverse flow directions on the coal rock cleat compression coefficient, and avoids the situation that the complete consistency of the test conditions is difficult to guarantee due to the manual change of the core direction in the prior art.
After the forward experiment is finished, the stop valve V of the pulse generator is closed1Outlet stop valve V5Opening the pipeline stop valve V6-V8Reverse outlet stop valve V9Regulating downstream pressure stop valve V4Ensuring the initial equilibrium helium pressure to be 9MPa (1300Psi), increasing the pressure value of the downstream gas bin to 9.2MPa through the pulse generator, and not allowing the upstream pressure sensor P in the boosting processuThe reading of (a) changes. Quick opening downstream pressure stop valve V4While recording the upstream pressure sensor PuDownstream pressure sensor PdThe value changes along with the time until the pressures of the upstream and downstream gas bins are re-balanced.
(6) After the forward or/and reverse experiment is finished, the confining pressure stop valve V is opened3And then slowly applying confining pressure to the coal rock in the rock core holder through a constant flow pump, wherein in the embodiment, the confining pressure is increased by 1-2 MPa every time, the change of the confining pressure is not less than 5 groups, and the maximum value of the confining pressure is not more than 20 MPa.
Based on the principle of a pressure pulse attenuation method, the coal rock permeability calculation formula is as follows:
wherein K is the gas permeability, 10-3μm2(mD); c is a unit mass conversion factor; μ is the aerodynamic viscosity, in units of mPa · s; l is the average length of the rock sample in cm; m is ln (Δ p)D) -the slope of the straight line segment of the t-curve; f. ofzIs a gas compression deviation factor; f. of1Is a mass flow correction factor; a is the cross-sectional area of the rock sample in cm2；PmIs the average pore pressure in MPa; vuIs the volume of the upstream gas bin in cm3；VdIs the volume of the downstream gas bin in cm3。
The permeability dimensionless ratio is the ratio of the coal rock permeability under different ambient pressure states to the coal rock permeability under the initial ambient pressure condition, the experimental condition is kept unchanged, and the permeability is only equal to PmAnd m, the calculation formula is as follows:
in the formula, K0The permeability of the coal rock under the initial confining pressure, mD; k is the permeability of the coal rock under the ambient pressure state, mD; m is0Is an initial confining pressure ln (Δ p)D) -the slope of the straight line segment of the t-curve; m is ln (Δ p) at different confining pressuresD) -the slope of the straight line segment of the t-curve; pm0The average pore pressure under the initial confining pressure is MPa; pmThe average pore pressure under different confining pressures, MPa.
(7) The coal rock cleat compression coefficient is a variable related to a loading path, and the experimental device can simulate the effective confining pressure change rule of the coal bed through loading, unloading and repeated loading (unloading), so as to research the influence of different effective confining pressure change rules on the cleat compression coefficient.
(8) And (4) unloading the confining pressure after the experiment is finished, taking out the rock sample, and collating the experimental data.
Step S303, establishing a coal rock cleat compression coefficient calculation model considering elastic deformation of the matrix, and determining the change rule of the cleat compression coefficient along with the effective confining pressure.
In this embodiment, the coal rock is simplified into a cube model, it is assumed that the matrix cube units are separated by equal-width cleats, when the effective confining pressure increases, the cleat compression and the matrix unit volume change both cause cleat width change, and finally show the change of permeability, through the derivation of a complex formula, the cleat compression coefficient is expressed as a function of a permeability dimensionless ratio, coal rock mechanical parameters and porosity, so as to establish a cleat compression coefficient calculation model:
in the formula (I), the compound is shown in the specification,Cfis a coefficient of compressibility of cleat, MPa-1(ii) a E is the elastic modulus of coal rock in MPa; nu is the Poisson ratio of the coal rock; phi is a0Coal rock porosity at initial confining pressure; delta PeThe difference between the coal rock ambient pressure and the initial ambient pressure is expressed in unit MPa; m slope of dimensionless logarithm of differential pressure versus time; pm0The average pore pressure under the initial confining pressure is unit MPa; pmMean pore pressure in MPa at different confining pressures.
According to one embodiment of the invention, the coal rock is taken from Zhengzhuang area of Shanxi Qinyi basin, the vitrinite reflectivity of the coal rock is 1.95%, and the coal rock belongs to high-order coal. The testing device and the testing method are used for testing the coal rock cleat compression coefficient. According to the test method, the porosity of the coal rock at normal temperature and under the initial ambient pressure of 0.4MPa is 4%, the elastic modulus is 3489MPa, and the Poisson ratio is 0.29. The maximum confining pressure adopted by the test is less than 16 MPa. In the embodiment, the numerical range of the coal rock cleat compression coefficient is measured to be 0.04-0.09, the effective confining pressure has a large influence on the cleat compression coefficient, the amplitude reduction is large when the effective confining pressure is less than 10MPa, and the amplitude reduction is gradual after the effective confining pressure is more than 10 MPa.
FIG. 4 is a graph of permeability dimensionless ratio as a function of effective confining pressure. When the effective confining pressure is less than 4MPa, the permeability dimensionless coefficient is rapidly reduced along with the effective confining pressure, and after the effective confining pressure is more than 4MPa, the reduction speed is slowed down. The pressure pulse attenuation method provided by the invention can quickly obtain the non-dimensional ratio of the permeability under different effective confining pressures, and greatly shortens the test time.
FIG. 5 is a change rule of the coal petrography cleat compression coefficient along with the effective confining pressure. The testing device realizes the determination of the cleat compression coefficients under the forward and reverse flow directions through a bypass pipeline of the testing device, and the results of the cleat compression coefficients tested by the forward and reverse flow directions are basically consistent as shown in FIG. 5, so that firstly, the helium can greatly reduce the chemical reaction of hydrophilic minerals in the coal rock and reduce the influence of media on a seepage channel; and secondly, the bypass pipeline realizes forward and reverse gas tests under the condition of no movement of the core, and changes of internal pores and cracks of the coal rock caused by external load changes are reduced.
Meanwhile, the invention also provides a system for determining the coal rock cleat compression coefficient, which comprises: the device comprises a coal-rock cleat compression coefficient testing device and a coal-rock cleat compression coefficient determining device; the coal-rock cleat compression coefficient determining device determines the coal-rock cleat compression coefficient according to the parameters collected by the coal-rock cleat compression coefficient testing device;
coal petrography cleat compression coefficient testing arrangement, include: the device comprises a pulse generator, an upstream gas bin, a rock core holder, a temperature controller, a temperature control box, a downstream gas bin, a helium tank and a constant flow pump;
an outlet of the pulse generator is connected to an inlet of the core holder through an upstream gas bin, an outlet of one end of a downstream gas bin is connected to an outlet of the core holder, an outlet of the other end of the downstream gas bin is connected with an outlet stop valve, a constant-flow pump is connected with an outer bin of the core holder through a high-pressure pipeline, an outlet of the pulse generator is also connected to an outlet of the other end of the downstream gas bin through a pipeline, the core holder is arranged in a temperature control box, a temperature controller is connected with the temperature control box to control the temperature of the temperature control box, and a helium tank is connected to an inlet of the pulse generator through a helium stop;
as shown in fig. 6, the coal petrography compressibility determining apparatus includes:
the initial parameter obtaining module 601 is used for obtaining the porosity, the elastic modulus and the poisson ratio of the coal rock of the rock sample under the initial confining pressure;
the pressure parameter determining module 602 is configured to determine a slope relationship between a dimensionless logarithm of differential pressure and time and an average pore pressure at different confining pressures according to differential pressures provided by applying different confining pressures to the rock sample;
the cleat compression coefficient determining module 603 is configured to determine a cleat compression coefficient according to a slope relationship between the dimensionless logarithm of differential pressure and time, a coal-rock porosity, an elastic modulus, a poisson ratio, an average pore pressure under different confining pressures, and a pre-established cleat compression coefficient model.
Meanwhile, as shown in fig. 7, the pressure parameter determining module 602 of the coal-rock cleat compression coefficient determining apparatus of this embodiment further includes:
a gas bin pressure obtaining unit 6031 configured to obtain upstream gas bin pressure data and downstream gas bin pressure data at different times when a pressure difference is provided to the rock sample;
a dimensionless pressure difference determination unit 6032 configured to determine a dimensionless pressure difference according to the upstream gas cabin pressure data, the downstream gas cabin pressure data, and the following equation at different times;
the present embodiment also provides an electronic device, which may be a desktop computer, a tablet computer, a mobile terminal, and the like, but is not limited thereto. In this embodiment, the electronic device may refer to the implementation of the foregoing method, and the contents thereof are incorporated herein, and repeated descriptions are omitted.
Fig. 8 is a schematic block diagram of a system configuration of an electronic apparatus 600 according to an embodiment of the present invention. As shown in fig. 6, the electronic device 600 may include a central processor 100 and a memory 140; the memory 140 is coupled to the central processor 100. Notably, this diagram is exemplary; other types of structures may also be used in addition to or in place of the structure to implement telecommunications or other functions.
In one embodiment, the functionality of the coal petrography compressibility determination method and/or apparatus may be integrated into the central processor 100. The central processing unit 100 may be configured to perform control to implement the following control:
determining the porosity, the elastic modulus and the Poisson ratio of the coal rock of the rock sample under the initial confining pressure;
applying different confining pressures to the rock sample to provide pressure difference, and determining the slope relation between the dimensionless logarithm of the pressure difference and time and the average pore pressure under different confining pressures;
and determining the cleat compression coefficient according to the slope relation between the dimensionless pressure difference logarithm and time, the coal-rock porosity, the elastic modulus, the Poisson ratio, the average pore pressure under different confining pressures and a pre-established cleat compression coefficient model.
That is, the functions of the method and the apparatus for determining the theorem-cutting compression factor in the embodiment of the present invention are realized by configuring and controlling the central processing unit 100.
As shown in fig. 8, the central processor 100, sometimes referred to as a controller or operational control, may include a microprocessor or other processor device and/or logic device, the central processor 100 receiving input and controlling the operation of the various components of the electronic device 600.
The memory 140 may be, for example, one or more of a buffer, a flash memory, a hard drive, a removable media, a volatile memory, a non-volatile memory, or other suitable device. The information relating to the failure may be stored, and a program for executing the information may be stored. And the central processing unit 100 may execute the program stored in the memory 140 to realize information storage or processing, etc.
The input unit 120 provides input to the cpu 100. The input unit 120 is, for example, a key or a touch input device. The power supply 170 is used to provide power to the electronic device 600. The display 160 is used to display an object to be displayed, such as an image or a character. The display may be, for example, an LCD display, but is not limited thereto.
The memory 140 may be a solid state memory such as Read Only Memory (ROM), Random Access Memory (RAM), a SIM card, or the like. There may also be a memory that holds information even when power is off, can be selectively erased, and is provided with more data, an example of which is sometimes called an EPROM or the like. The memory 140 may also be some other type of device. Memory 140 includes buffer memory 141 (sometimes referred to as a buffer). The memory 140 may include an application/function storage section 142, and the application/function storage section 142 is used to store application programs and function programs or a flow for executing the operation of the electronic device 600 by the central processing unit 100.
The memory 140 may also include a data store 143, the data store 143 for storing data, such as contacts, digital data, pictures, sounds, and/or any other data used by the electronic device. The driver storage portion 144 of the memory 140 may include various drivers of the electronic device for communication functions and/or for performing other functions of the electronic device (e.g., messaging application, address book application, etc.).
The communication module 110 is a transmitter/receiver 110 that transmits and receives signals via an antenna 111. The communication module (transmitter/receiver) 110 is coupled to the central processor 100 to provide an input signal and receive an output signal, which may be the same as in the case of a conventional mobile communication terminal.
Based on different communication technologies, a plurality of communication modules 110, such as a cellular network module, a bluetooth module, and/or a wireless local area network module, may be provided in the same electronic device. The communication module (transmitter/receiver) 110 is also coupled to a speaker 131 and a microphone 132 via an audio processor 130 to provide audio output via the speaker 131 and receive audio input from the microphone 132 to implement general telecommunications functions. Audio processor 130 may include any suitable buffers, decoders, amplifiers and so forth. In addition, an audio processor 130 is also coupled to the central processor 100, so that recording on the local can be enabled through a microphone 132, and so that sound stored on the local can be played through a speaker 131.
An embodiment of the present invention further provides a computer-readable program, where when the program is executed in an electronic device, the program causes a computer to execute the coal petrography compressibility determination method as described above in the electronic device.
An embodiment of the present invention further provides a storage medium storing a computer-readable program, where the computer-readable program enables a computer to execute a method for determining a coal-rock cleat compression coefficient in an electronic device.
The preferred embodiments of the present invention have been described above with reference to the accompanying drawings. The many features and advantages of the embodiments are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the embodiments that fall within the true spirit and scope thereof. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the embodiments of the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope thereof.
For those skilled in the art, the implementation of the coal-rock cleat compression coefficient determining system in the embodiment of the present invention can be known from the foregoing description about the embodiments of the method and the apparatus, and therefore, the details are not repeated again.
In order to solve the problems in the coal rock cleat compression coefficient test, the invention provides a simple and practical test device and a cleat compression coefficient test method based on a pressure pulse attenuation method. The invention considers the influence of the elastic deformation of the coal rock matrix on the change of the cleat width, greatly shortens the test time by adopting an unsteady state pressure pulse attenuation method, can simulate the influence of different coal bed temperatures on the cleat compression coefficient, and realizes the cleat compression coefficient test of the gas medium in the positive and reverse seepage directions.
The invention provides a simple and practical testing device and a cleat compression coefficient testing method based on a pressure pulse attenuation method, which consider the influence of elastic deformation of a coal rock matrix on cleat width change, greatly shorten the testing time by adopting an unsteady state pressure pulse attenuation method, simulate the influence of different coal bed temperatures on the cleat compression coefficient and realize the cleat compression coefficient testing of a gas medium in two seepage directions of forward and reverse directions.
As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The principle and the implementation mode of the invention are explained by applying specific embodiments in the invention, and the description of the embodiments is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.
Claims (10)
1. A coal petrography compressed coefficient determining method is characterized in that the method determines the coal petrography compressed coefficient by using a coal petrography compressed coefficient testing device, and the method comprises the following steps:
determining the porosity, the elastic modulus and the Poisson ratio of the coal rock of the rock sample under the initial confining pressure;
applying different confining pressures to the rock sample to provide pressure difference, and determining the slope relation between the dimensionless logarithm of the pressure difference and time and the average pore pressure under different confining pressures;
determining a cleat compression coefficient according to a slope relation between the dimensionless pressure difference logarithm and time, the porosity of coal and rock, the elastic modulus, the Poisson ratio, the average pore pressure under different confining pressures and a pre-established cleat compression coefficient model; wherein the content of the first and second substances,
the coal rock cleat compression coefficient testing device comprises: the device comprises a pulse generator, an upstream gas bin, a rock core holder, a temperature controller, a temperature control box, a downstream gas bin, a helium tank and a constant flow pump; wherein the content of the first and second substances,
an outlet of the pulse generator is connected to an inlet of the core holder through an upstream gas bin, an outlet of one end of the downstream gas bin is connected with an outlet of the core holder, an outlet of the other end of the downstream gas bin is connected with an outlet stop valve, a constant-flow pump is connected with an outer bin of the core holder through a high-pressure pipeline, an outlet of the pulse generator is also connected to an outlet of the other end of the downstream gas bin through a pipeline, the core holder is arranged in a temperature control box, a temperature controller is connected with the temperature control box to control the temperature of the temperature control box, and a helium tank is connected to an inlet of the pulse generator through a helium stop valve;
providing a pressure differential to the rock sample, and determining a slope relationship of a dimensionless logarithm of the pressure differential versus time comprises:
providing pressure difference for the rock sample, and acquiring upstream gas bin pressure data and downstream gas bin pressure data at different moments;
determining a dimensionless pressure difference according to the upstream gas bin pressure data, the downstream gas bin pressure data and the following formula at different moments;
wherein, Δ pD(t) is the dimensionless pressure differential at time t; p is a radical of1(t) is the upstream gas bin pressure at time t; p is a radical of2(t) is the downstream gas bin pressure at time t; p is a radical of1(0) The pressure of the upstream gas bin at the initial moment; p is a radical of2(0) Is the initial time downstream gas bin pressure; Δ p (t) is the pressure difference between the upstream and downstream gas bins at time t; delta p (0) is the pressure difference between the upstream gas bin and the downstream gas bin at 0 moment;
determining the slope of the logarithm of the dimensionless pressure difference and the time according to the dimensionless pressure difference and the following formula;
wherein m is the slope of the dimensionless logarithm of the differential pressure with time; n is the number of counting points; t is tnTime for the nth calculation point; t is tn-1Time for the n-1 st calculation point; Δ p (t)n) Is tnThe pressure difference of the upstream and downstream gas bins at the moment; Δ p (t)n-1) Is tn-1The pressure difference of the upstream and downstream gas bins at the moment; p is a radical of2(tn) Is tnThe downstream gas bin pressure at time; p is a radical of2(tn-1) Is tn-1The downstream gas bin pressure at time;
the pre-established cleat compression coefficient model is as follows:
wherein, CfA cleat compression factor; e is the elastic modulus of coal rock; nu is the Poisson ratio of the coal rock; phi is a0Coal rock porosity at initial confining pressure; delta PeThe difference between the coal rock ambient pressure and the initial ambient pressure is obtained, and the slope of the dimensionless logarithm of the differential pressure and the time is m; pm0The average pore pressure at the initial confining pressure; pmThe average pore pressure at different confining pressures.
2. The method for determining the coal-rock secant compression coefficient as claimed in claim 1, wherein when different confining pressures are applied to the rock sample, 1 MPa-2 MPa is added each time, the variation of the confining pressure is not less than 5 groups, and the maximum value of the confining pressure is not more than 20 MPa.
3. A method for determining a coal-rock cleat compression factor as defined in claim 1, wherein the apparatus further comprises: a confining pressure sensor, an upstream pressure sensor and a downstream pressure sensor;
the upstream pressure sensor is connected to the upstream pressure bin, the downstream pressure sensor is connected to the downstream pressure bin, and the confining pressure sensor is arranged between the advection pump and the outer bin of the core holder.
4. A method for determining a coal-rock cleat compression factor as defined in claim 1, wherein the apparatus further comprises:
the pulse generator stop valve is arranged between the pulse generator and the upstream gas bin;
the upstream pressure stop valve is arranged between the upstream gas bin and the core holder;
the downstream pressure stop valve is arranged between the rock core holder and the downstream gas bin;
the confining pressure stop valve is arranged between the confining pressure sensor and the constant flow pump;
and the bypass stop valve is arranged on pipelines of the outlet of the pulse generator and the outlet of the other end of the downstream gas bin.
5. A system for determining a coal-rock cleat compressibility, the system comprising: the device comprises a coal-rock cleat compression coefficient testing device and a coal-rock cleat compression coefficient determining device; wherein the content of the first and second substances,
coal petrography cleat compression coefficient testing arrangement, include: the device comprises a pulse generator, an upstream gas bin, a rock core holder, a temperature controller, a temperature control box, a downstream gas bin, a helium tank and a constant flow pump; wherein the content of the first and second substances,
an outlet of the pulse generator is connected to an inlet of the core holder through an upstream gas bin, an outlet of one end of the downstream gas bin is connected with an outlet of the core holder, an outlet of the other end of the downstream gas bin is connected with an outlet stop valve, a constant-flow pump is connected with an outer bin of the core holder through a high-pressure pipeline, an outlet of the pulse generator is also connected to an outlet of the other end of the downstream gas bin through a pipeline, the core holder is arranged in a temperature control box, a temperature controller is connected with the temperature control box to control the temperature of the temperature control box, and a helium tank is connected to an inlet of the pulse generator through a helium stop valve;
the coal rock cleat compression coefficient determining device comprises:
the initial parameter acquisition module is used for acquiring the porosity, the elastic modulus and the Poisson ratio of the coal rock of the rock sample under the initial confining pressure;
the pressure parameter determination module is used for applying pressure differences provided by different confining pressures to the rock sample and determining the slope relation between the dimensionless logarithm of the pressure difference and time and the average pore pressure under different confining pressures;
the cleat compression coefficient determining module is used for determining the cleat compression coefficient according to the slope relation between the dimensionless pressure difference logarithm and time, the coal rock porosity, the elastic modulus, the Poisson ratio, the average pore pressure under different confining pressures and a pre-established cleat compression coefficient model; wherein the content of the first and second substances,
the pressure parameter determination module comprises:
the gas bin pressure acquisition unit is used for acquiring upstream gas bin pressure data and downstream gas bin pressure data at different moments when pressure difference is provided for the rock sample;
the dimensionless pressure difference determining unit is used for determining the dimensionless pressure difference according to the upstream gas bin pressure data, the downstream gas bin pressure data and the following formula at different moments;
wherein, Δ pD(t) is the dimensionless pressure differential at time t; p is a radical of1(t) is the upstream gas bin pressure at time t; p is a radical of2(t) is the downstream gas bin pressure at time t; p is a radical of1(0) The pressure of the upstream gas bin at the initial moment; p is a radical of2(0) Is the initial time downstream gas bin pressure; Δ p (t) is the pressure difference between the upstream and downstream gas bins at time t; delta p (0) is the pressure difference between the upstream gas bin and the downstream gas bin at 0 moment;
determining the slope of the logarithm of the dimensionless pressure difference and the time according to the dimensionless pressure difference and the following formula;
wherein m is the slope of the dimensionless logarithm of the differential pressure with time; n is the number of counting points; t is tnTime for the nth calculation point; t is tn-1Time for the n-1 st calculation point; Δ p (t)n) Is tnThe pressure difference of the upstream and downstream gas bins at the moment; Δ p (t)n-1) Is tn-1The pressure difference of the upstream and downstream gas bins at the moment; p is a radical of2(tn) Is tnThe downstream gas bin pressure at time; p is a radical of2(tn-1) Is tn-1The downstream gas bin pressure at time;
the pre-established cleat compression coefficient model is as follows:
wherein, CfA cleat compression factor; e is the elastic modulus of coal rock; nu is the Poisson ratio of the coal rock; phi is a0Coal rock porosity at initial confining pressure; delta PeThe difference between the coal rock ambient pressure and the initial ambient pressure is obtained, and the slope of the dimensionless logarithm of the differential pressure and the time is m; pm0The average pore pressure at the initial confining pressure; pmThe average pore pressure at different confining pressures.
6. The coal-rock cleat compression coefficient determining system of claim 5, wherein when different ambient pressures are applied to the rock sample by using the coal-rock cleat compression coefficient testing device, 1 MPa-2 MPa is added each time, the ambient pressure changes by not less than 5 groups, and the maximum value of the ambient pressure is not more than 20 MPa.
7. The coal-rock cleat compression factor determination system of claim 5, wherein the coal-rock cleat compression factor testing device further comprises: a confining pressure sensor, an upstream pressure sensor and a downstream pressure sensor;
the upstream pressure sensor is connected to the upstream pressure bin, the downstream pressure sensor is connected to the downstream pressure bin, and the confining pressure sensor is arranged between the advection pump and the outer bin of the core holder.
8. The coal-rock cleat compression factor determination system of claim 5, wherein the coal-rock cleat compression factor testing device further comprises:
the pulse generator stop valve is arranged between the pulse generator and the upstream gas bin;
the upstream pressure stop valve is arranged between the upstream gas bin and the core holder;
the downstream pressure stop valve is arranged between the rock core holder and the downstream gas bin;
the confining pressure stop valve is arranged between the confining pressure sensor and the constant flow pump;
and the bypass stop valve is arranged on pipelines of the outlet of the pulse generator and the outlet of the other end of the downstream gas bin.
9. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the method of any one of claims 1 to 4 when executing the computer program.
10. A computer-readable storage medium, characterized in that the computer-readable storage medium stores a computer program for executing the method of any one of claims 1 to 4.
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