Underground water-sealed cave storage real three-dimensional fissure network seepage simulation method and electronic device

Abstract

The application provides a groundwater-sealed cavern real three-dimensional fissure network seepage simulation method and electronic equipment, the application is based on the fissure exposed by the excavation of the groundwater-sealed cavern to model, the fissure parameters are basically consistent with the actual situation, the difference of the fissure characteristics and the fissure distribution characteristics in the excavation area is reflected, the seepage characteristics of the groundwater-sealed cavern groundwater in the water-bearing medium are truly reflected, and the fissure connectivity and the seepage distribution difference of different regions of the water-bearing medium can be more accurately characterized. The fissure network seepage model of the groundwater-sealed cavern in different stages is constructed, the change of the groundwater in the construction process of the groundwater-sealed cavern can be analyzed, the seepage quantity prediction analysis can be carried out, and the prediction analysis of the cavern seepage quantity and the groundwater level in the operation process of the groundwater-sealed cavern can be carried out.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of dynamic creation of hydrogeological models of underground water-sealed caverns, and particularly relates to a real three-dimensional fissure network seepage simulation method and electronic device for underground water-sealed caverns. BACKGROUND

[0002] An underground water-sealed cavern refers to a certain volume of caverns formed by artificial excavation in rock mass below a stable groundwater level to store petroleum products, and groundwater flows into the caverns from the surrounding rock fissures to achieve sealed oil storage through design control. The underground water-sealed cavern has the advantages of large storage capacity, safety and reliability, low cost, etc., and is one of the important storage methods for strategic energy such as petroleum. It is gradually replacing the ground storage method and becoming the mainstream storage method for strategic energy.

[0003] The most core technical problem in the field of underground water-sealed cavern engineering is how to accurately predict and precisely control the water seepage of the oil storage cavern under the premise of ensuring water sealing safety. Therefore, in the construction and operation process of the underground water-sealed cavern, a three-dimensional hydrogeological model needs to be built to intuitively express the groundwater storage and migration process, accurately depict the heterogeneity and anisotropy of the water-containing medium, and then accurately describe the groundwater seepage field and control the groundwater flow elements.

[0004] The fissure network developed in the surrounding rock of the underground water-sealed cavern is the main channel for groundwater flow. However, due to the irregularity of fissure development, the fissure properties are difficult to accurately determine, and the modeling methods commonly used in underground water-sealed caverns, such as equivalent continuous medium method, discrete fissure network method and double medium method, can only make a generalization of the fissure network seepage. The equivalent continuous medium method ignores the fissure and equivalent to the fissure as a porous medium, which cannot reflect the uneven distribution of permeability coefficient and water quantity in the reservoir area. The discrete fissure network method regards the fissure as a discrete entity, and constructs a fissure network model by defining the geometric properties (such as length, width, direction, etc.) and mutual connection relationship of the fissure, and generates a random fissure network by statistical fissure law in the reservoir area (ignoring the pore), which cannot reflect the fissure connectivity characteristics of each cavern. The double medium method is a combination of the above two methods, and the fissure is randomly generated for modeling. SUMMARY

[0005] The purpose of the present application is to provide a real three-dimensional fissure network seepage simulation method and electronic device for underground water-sealed caverns to solve the problems in the prior art, and to establish a real three-dimensional fissure seepage network model, which reflects the differences in fissure characteristics and fissure distribution characteristics of the underground water-sealed cavern.

[0006] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0007] A real three-dimensional fissure network seepage simulation method for underground water-sealed caverns, comprising the following steps:

[0008] S1: obtaining geological data of the underground water-sealed cavern, the geological data including engineering geological data, hydrogeological data, topographic and geomorphic data, engineering layout, hydrogeological test and data, drilling and geophysical prospecting data;

[0009] S2: determining the surface topography, stratum lithology distribution and boundary surface, spatial position and shape of faults of the underground water-sealed cavern according to the geological data;

[0010] S3: constructing an initial generalized geometric model according to the surface topography, stratum lithology distribution and boundary surface, spatial position and shape of faults, and engineering range of the underground water-sealed cavern;

[0011] S4: obtaining the permeability coefficient of the initial generalized geometric model from the hydrogeological test and data, obtaining the boundary condition of the initial generalized geometric model according to the atmospheric precipitation speed, river water level and underground water level limit in the hydrogeological data, and forming an initial generalized hydrogeological model;

[0012] S5: obtaining the fissure parameters in the construction and excavation stage of the underground water-sealed cavern, constructing fissures on the initial generalized hydrogeological model, and forming an initial three-dimensional fissure network seepage model;

[0013] S6: adjusting the fissure opening degree in the initial three-dimensional fissure network seepage model, obtaining the simulated seepage quantity under different fissure opening degrees, comparing the simulated seepage quantity and the measured seepage quantity, taking the fissure opening degree when the error between the two is less than an error threshold as the fissure opening degree in the initial three-dimensional fissure network seepage model, and obtaining a three-dimensional fissure network seepage model.

[0014] The present application is based on the fissures revealed by excavation for modeling, the fissure parameters are basically consistent with the actual situation, the differences in fissure characteristics and fissure distribution characteristics in the excavation area are reflected, and the seepage characteristics of the underground water-sealed cavern underground water in the water-bearing medium are truly reflected, so that the fissure connectivity and seepage distribution differences of different regions of the water-bearing medium can be more accurately characterized.

[0015] Further, the boundary surface is formed by connecting and combining the same stratum boundary elevations in different drill holes and geophysical prospecting profiles; and the spatial position and shape of the faults are determined according to the drilling, geophysical prospecting data and actual excavation revealed conditions, and the occurrence, width, extension depth and length thereof are determined.

[0016] Further, the boundary condition of the initial generalized geometric model includes the atmospheric precipitation infiltration speed and the boundary pressure water head.

[0017] Further, the fissure parameters include the fissure occurrence, adjacent fissure spacing, fissure spatial position and fissure trace length.

[0018] Furthermore, the length of the fissure trace is calculated based on the fissures exposed at the same location in adjacent facilities. If the fissures at the same location in adjacent facilities have the same orientation, the fissures are merged into one fissure, and the length of the fissure trace is calculated.

[0019] Furthermore, using the aforementioned three-dimensional fracture network seepage simulation method for underground water-sealed caverns, three-dimensional fracture network seepage models are obtained for at least two engineering stages, including the layered excavation stage of the underground water-sealed cavern, the airtightness test stage, the operation stage, and the expansion stage.

[0020] Furthermore, based on the seepage volume and water level of the three-dimensional fractured network seepage model in this stage, and the three-dimensional fractured network seepage model in the next stage, the seepage volume and water level in the next stage are obtained. This invention constructs fractured network seepage models for different engineering stages, enabling the analysis of groundwater changes and the prediction of seepage volume during the construction and operation of underground water-sealed caverns.

[0021] Based on the same inventive concept, the present invention also provides an electronic device, comprising:

[0022] One or more processors;

[0023] A memory storing one or more programs, which, when executed by one or more processors, cause the one or more processors to implement the steps of a method for simulating seepage through a real three-dimensional fracture network in underground water-sealed caverns.

[0024] Based on the same inventive concept, the present invention also provides a computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, it implements the steps of a method for simulating the seepage of a real three-dimensional fracture network in an underground water-sealed cavern.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] This invention models the fractures exposed during excavation, with fracture parameters consistent with actual conditions. It reflects the differences in fracture characteristics and distribution in the excavated area, and accurately reflects the seepage characteristics of groundwater in the aquifer medium of the groundwater-sealed cavern. It can more accurately characterize the fracture connectivity and seepage distribution differences in different areas of the aquifer medium.

[0027] This invention constructs a fracture network seepage model for different stages, which can realize the analysis of groundwater changes and the prediction of seepage volume during the construction of underground water-sealed caverns, as well as the prediction and analysis of cavern seepage volume and groundwater level during the operation of underground water-sealed caverns. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the flow simulation method for three-dimensional fracture network seepage in underground water-sealed caverns according to the present invention. DETAILED DESCRIPTION

[0029] The application will be described in detail below with reference to the embodiments. It should be noted that the embodiments in the application and the features in the embodiments can be combined with each other without conflict. For the convenience of description, if the terms “up”, “down”, “left” and “right” appear in the following, they only indicate the up, down, left and right directions of the drawings themselves, and do not limit the structure.

[0030] EMBODIMENT

[0031] As Figure 1 A method for creating and applying a three-dimensional fracture network seepage model of a groundwater-sealed underground warehouse includes the following steps:

[0032] Step 1, collecting geological data of a groundwater-sealed underground warehouse research area; the geological data includes engineering geological data, hydrogeological data, topographic and geomorphic data, engineering layout, hydrogeological test and data, drilling and geophysical prospecting data, etc.

[0033] Step 2, determining the surface topography and analyzing the rock stratum and fault structure characteristics through the geological data.

[0034] The rock stratum and fault structure characteristics mainly include the stratum lithology distribution and boundary surface, spatial position and shape and size of the fault; the stratum lithology distribution and boundary surface can be determined through drilling and geophysical prospecting data, and the boundary surface is formed by connecting and combining the same stratum boundary elevations in different drill holes and geophysical prospecting profiles; the spatial position and shape of the fault need to determine its occurrence (trend and dip angle), width, extension depth and length according to the drilling, geophysical prospecting data and actual excavation exposure data. The occurrence refers to the trend and dip angle of the geological structure.

[0035] Step 3, constructing an initial generalized geometric model in a multi-physical field coupling software according to the determined surface topography and analyzed rock stratum and fault structure characteristics, and engineering range requirements.

[0036] The initial generalized geometric model includes the surface topography, stratum, fault and geological boundary; the surface topography is constructed by a discrete smooth interpolation method, that is, the surface contour lines are extracted according to the surveying or satellite detection data, and the three-dimensional surface is constructed by combining the refinement function (inserting a coordinate point in the middle when the positions of two coordinate points are far apart) in the multi-physical field coupling software; the stratum is constructed by generating a corresponding entity model through the boundary surface, that is, the boundary elevations between different strata are determined according to the distribution of each stratum (stratum thickness and elevation) revealed by each exploration hole, and then the three-dimensional boundary surface is constructed, and the entity between different boundary surfaces is constructed as the stratum; the fault is constructed by generating a corresponding entity according to the determined fault information; and the geological boundary is determined by cutting the surface topography, stratum and fault according to the engineering range.

[0037] Step 4, determine the physical parameters and boundary conditions in the initial generalized geometric model, form the initial generalized hydrogeological model, and check the physical parameters and boundary conditions.

[0038] The physical parameters are mainly the permeability coefficients of different strata and faults determined according to hydrogeological tests such as borehole water pressure test, oscillation test, and water injection test, and the test data; the boundary conditions are the atmospheric rainfall infiltration rate and the boundary pressure water head, which need to be determined through the atmospheric rainfall conditions in the hydrogeological data (the average rainfall speed is calculated by dividing the annual or recent years' atmospheric precipitation by time, and is taken as the initial rainfall infiltration speed), the water level of the surrounding rivers, and the water level limit of the underground water (the pressure water head at the water surface is 0, and gradually increases with the depth, so only the water level of the rivers and the water level of the underground water need to be determined, and the pressure water head at different elevations can be determined); the check of the physical parameters and the boundary conditions is performed by comparing the simulated water level with the measured water level; the simulated water level is obtained by extracting the pressure at the bottom of the water level monitoring hole in the model and converting it into water head, while the measured water level is directly obtained from the piezometer data in the field water level monitoring hole; the most appropriate physical parameters and boundary conditions are checked by adjusting the rainfall infiltration speed or the boundary pressure water head so that the simulated water level is consistent with the measured water level.

[0039] Step 5, statistics of construction excavation to reveal fissures, and establishment of a real three-dimensional fissure network seepage model.

[0040] After the excavation of the cavern, the fissures can be clearly seen at the cave wall, and the occurrence and density of the fissures can be obtained through geological mapping. At the same time, the position of the fissure revealed in the tunnel section can be taken as the spatial position of the fissure. The construction excavation here refers only to the excavation statistics of the construction tunnel, water curtain tunnel, and upper layer excavation of the cavern, and does not include the excavation of other layers of the cavern; the cavern generally needs to be excavated in layers, which can be divided into upper, middle, and lower layers of excavation; the statistics of the fissures need to include the occurrence, spacing, spatial position, and trace length of the fissures; the trace length of the fissures needs to be inferred from the fissures revealed at the same part of the adjacent facilities. If the fissures revealed at the same part of the adjacent facilities have the same occurrence, they can be combined into the same fissure, and the trace length is at least the distance between the two facilities. For example, if there are two adjacent caverns No. 1 and No. 2, and a group of fissures are revealed at a certain place in Cavern No. 1, and the group of fissures is extended to intersect with Cavern No. 2. If no fissures are revealed at this place in Cavern No. 2 by excavation, it indicates that the length of the fissures will not reach Cavern No. 2. If the fissures are revealed, it indicates that the length of the fissures can at least reach Cavern No. 2. The real fissure network is constructed by arranging and combining the fissures in the corresponding positions in the initial generalized model, forming a real three-dimensional fissure network seepage model.

[0041] Step 6, determination and check of the fissure opening in the real three-dimensional fissure network model.

[0042] The initial value of the fracture opening degree can be estimated and determined through hydrogeological data, water curtain hole single-hole water injection drawdown test and data, grouting hole water pressure test and data, and fracture characteristics, that is, the permeability coefficient is calculated according to the relevant test results and taken as the fracture permeability coefficient, and then the opening degree is determined according to the fracture permeability coefficient calculation method; the fracture opening degree needs to be checked according to the comparison between the simulation and measured results of the underground water level and seepage quantity, and the fracture opening degree value of the grouting area needs to be distinguished according to the measured water quantity and the distribution of the grouting area, that is, the fracture opening degree is adjusted and simulated to obtain the seepage quantity of different parts of the cavern, and the simulated seepage quantity and the measured seepage quantity of different parts are compared; when the results of the two are consistent, it is indicated that the checking is completed.

[0043] Step 7, a real three-dimensional fracture network seepage model of different stages is established, and then seepage field simulation checking and prediction analysis application is carried out.

[0044] Different stages mainly include the cavern stratified excavation stage, the air tightness test stage, the operation stage, the expansion stage and the like; the seepage field analysis needs to construct the corresponding model in the real three-dimensional fracture network seepage model according to the engineering excavation condition of different stages and determine the corresponding engineering facility boundary condition, so as to realize accurate prediction analysis of the water level, seepage quantity and the relationship between recharge and runoff; the prediction is the numerical simulation of the next stage based on the model parameters checked according to the seepage quantity and water level of the current stage and the geometric model of the next stage, so as to obtain the water level, seepage quantity and the like of the next stage; the model checking needs to be dynamically checked according to the comparison between the measured water level, water quantity change and simulation results of different stages, mainly adjusting the geometric structure of the fracture network and the fracture opening degree of different regions, that is, the simulation water level and water quantity results of each stage are compared with the measured water level and water quantity results, the differences between the two are analyzed, the reasons for the differences are determined combined with the geological information and related measures revealed by each stage construction, so as to adjust the geometric structure and the fracture opening degree, and then the simulation is carried out again until the simulation results are consistent with the measured results.

[0045] The model creation method provided in the embodiment constructs the fracture network exposed by excavation, the distribution and occurrence of which are basically consistent with the actual situation, the fracture conditions of each cavern are consistent with the actual situation but are different from each other, the distribution of the spatial position of the fracture is considered, instead of being randomly generated, can fully reflect the fracture development and distribution of the reservoir area, and then reflect the fracture connectivity and seepage characteristics of the reservoir area. The development and distribution characteristics of the fracture network of the surrounding rock of the underground water sealed cavern can be finely described, the fracture connectivity and seepage distribution difference of different regions of the water-bearing medium can be accurately represented, and the seepage characteristics of the underground water in the water-bearing medium in the construction and operation process of the underground water sealed cavern can be truly reflected, so as to provide a more accurate technical means and method for the seepage field analysis of the underground water sealed cavern.

[0046] The model application method provided by the embodiment can obtain more actual simulation results, including pressure, flow lines and seepage amount of each part of the model, through simulation calculation, because the geometry and related physical parameters of the established model are basically consistent with the actual situation. The water level can be converted from the pressure of each part of the model, the flow direction of the underground water in the reservoir area can be determined through the flow lines, and the seepage amount is obtained by flux calculation on the wall surface of each tunnel and chamber. In this model, whether the geometry or the physical parameters are adjusted, the pressure, flow lines and seepage amount will all change accordingly. The change analysis of the underground water in the construction process of the underground water sealed cavern reservoir, the prediction analysis of the seepage amount, the prediction analysis of the water curtain system water supplement amount, the seepage amount of the oil storage chamber and the underground water level in the operation process of the underground water sealed cavern reservoir can be realized. When the cavern reservoir is expanded, the entire geometric model will be modified first, and then the corresponding construction measures and physical parameters will be set, which will all cause the flow lines, pressure and seepage amount of the existing reservoir area to change, and the mutual influence between the expanded cavern reservoir and the operated cavern reservoir can be evaluated.

[0047] The embodiment provides an electronic device, which comprises:

[0048] one or more processors;

[0049] a memory having one or more programs stored thereon, which, when executed by the one or more processors, cause the one or more processors to implement the steps of the true three-dimensional fissure network seepage simulation method of the underground water sealed cavern reservoir.

[0050] In some implementations, the memory can be a high-speed random access memory (RAM) and can also include a non-volatile memory, such as at least one disk memory.

[0051] In other implementations, the processor can be a central processing unit (CPU), a digital signal processor (DSP) or various types of general-purpose processors, which are not limited herein.

[0052] The embodiment provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the steps of the three-dimensional fissure network seepage simulation method of the underground water sealed cavern reservoir.

[0053] The content illustrated in the above embodiments should be understood as the embodiments merely for more clearly illustrating the present application, and should not be used to limit the scope of the present application. After reading the present application, various equivalent modifications of the present application made by those skilled in the art all fall within the scope defined by the appended claims of the present application.

Claims

1. A method of true 3D fracture network flow simulation for a groundwater sealed cavern, characterized in that, The method comprises the following steps: S1: obtaining geological data of the underground water-sealed cavern, wherein the geological data comprises engineering geological data, hydrogeological data, topographic and geomorphic data, engineering layout, hydrogeological test and data, drilling and geophysical prospecting data; S2: determining the surface topography, stratum lithology distribution and boundary surface, spatial position and shape of faults of the underground water-sealed cavern according to the geological data; S3: constructing an initial generalized geometric model according to the surface topography, stratum lithology distribution and boundary surface, spatial position and shape of faults and the engineering range of the underground water-sealed cavern; S4: obtaining the permeability coefficient of the initial generalized geometric model from the hydrogeological test and data, obtaining the boundary condition of the initial generalized geometric model according to the atmospheric precipitation speed, river water level and underground water level limit in the hydrogeological data, and forming an initial generalized hydrogeological model; S5: obtaining the fracture parameters in the construction and excavation stage of the underground water-sealed cavern, constructing fractures on the initial generalized hydrogeological model to form an initial three-dimensional fracture network seepage model; S6: adjusting the fracture aperture in the initial three-dimensional fracture network seepage model, obtaining the simulated seepage quantity under different fracture apertures, comparing the simulated seepage quantity with the measured seepage quantity, and taking the fracture aperture when the error between the simulated seepage quantity and the measured seepage quantity is less than an error threshold as the fracture aperture in the initial three-dimensional fracture network seepage model to obtain a three-dimensional fracture network seepage model.

2. The true 3D fracture network flow simulation method for a groundwater sealed storage cavern according to claim 1, characterized in that, The boundary surface is formed by connecting and combining the same stratum boundary elevations in different boreholes and geophysical prospecting profiles; and the spatial position and shape of the faults are determined according to the drilling, geophysical prospecting data and actual excavation exposure conditions to determine the occurrence, width, extension depth and length thereof.

3. The true 3-D fracture network flow simulation method of the groundwater sealed storage according to claim 1, characterized in that, The boundary condition of the initial generalized geometric model comprises the atmospheric precipitation infiltration speed and boundary pressure water head.

4. The true 3-D fracture network flow simulation method of groundwater sealed storage cavern according to claim 1, characterized in that, The fracture parameters comprise the fracture occurrence, adjacent fracture spacing, fracture spatial position and fracture trace length.

5. The true 3D fracture network flow simulation method of a groundwater sealed storage according to claim 4, characterized in that, The fracture trace length is calculated according to the fracture exposure conditions of the same parts of adjacent facilities; if the fractures of the same parts of adjacent facilities have the same occurrence, the fractures are combined into one fracture, and the fracture trace length is calculated.

6. The true 3-D fracture network flow simulation method of groundwater sealed storage caverns according to claim 1, characterized in that, The three-dimensional fracture network seepage model of each engineering stage is obtained by using the three-dimensional fracture network seepage simulation method of the underground water-sealed cavern, and the engineering stages comprise the stratified excavation stage, the air tightness test stage, the operation stage and the expansion stage of the underground water-sealed cavern.

7. The true 3D fracture network flow simulation method of a groundwater sealed cave storage according to claim 6, characterized in that, The seepage quantity and water level of the next stage are obtained according to the seepage quantity and water level of the three-dimensional fracture network seepage model of the present stage and the three-dimensional fracture network seepage model of the next stage.

8. An electronic device, comprising: The method comprises: one or more processors; a memory having one or more programs stored thereon, which, when executed by the one or more processors, cause the one or more processors to implement the steps of the method according to any one of claims 1-7.

9. A computer-readable storage medium, characterized in that, The computer program stored in the memory is executed by the processor to implement the steps of the method according to any one of claims 1-7.

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