A method and system for simulating and optimizing a particle impact rock breaking process

Abstract

The application provides a particle impact rock breaking process simulation optimization method and system, adopts computational fluid dynamics to simulate the flow of drilling fluid in a three-dimensional pipeline, adopts a digital elevation model to simulate the flow of impact particles in the drilling fluid and the process of spraying the impact particles onto a rock mass, realizes the representation of the breaking degree of the rock mass based on the fracture of parallel adhesive bonds in a rock stratum model, represents the wear range of the pipeline based on the stress distribution in a spray pipe, represents the blockage in the spray pipe based on the particle accumulation position in the spray pipe, obtains the damage effect of the particle impact rock breaking process on the rock mass under the current simulation parameters, and determines a particle impact rock breaking process optimization scheme suitable for actual operation conditions based on the analysis results. The application can overcome the deficiency of the existing particle impact rock breaking simulation method in parameter representation, optimize the particle impact rock breaking process, and improve the production efficiency.

Description

Technical Field

[0001] This invention belongs to the field of high-speed particle impact rock breaking simulation technology, and relates to a particle impact rock breaking process simulation optimization method and system. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] In the early stages of oil and natural gas extraction, the hardness of deep rock formations limited mining to shallow strata. However, with continuous industrial development, shallow surface oil and gas resources have become insufficient to meet industrial demands, making the development of deep-seated oil resources a crucial task in oil and gas exploration. But during extraction, rock hardness and extraction difficulty increase with depth. Therefore, improving the rock-breaking speed in hard rock formations is a pressing research challenge.

[0004] Currently, rock breaking technologies can be classified into three types based on their mechanisms: hydraulic rock breaking, mechanical rock breaking, and particle impact rock breaking. Hydraulic rock breaking refers to the technology of using high-pressure water jets exceeding 20 MPa to break rocks. Mechanical rock breaking refers to using special cutting drill bits to tunnel through formations. Particle impact rock breaking involves injecting particles into a high-speed liquid through a particle injection system after the drilling fluid is pumped out. The particles are then transported to the drill bit at the bottom of the well via a high-pressure pipeline. The particles are eventually accelerated to the drilling fluid velocity and then ejected from a special PID drill bit nozzle, impacting the formation to break the rock. Finally, intact particles are separated from the drilling fluid returning from the wellhead, achieving particle recycling. The drilling speed of particle impact rock breaking is generally 3-4 times that of conventional drilling speeds, and it does not generate dust. It is easy to centrally control and greatly shortens the drilling cycle, showing great potential in applications in deep, hard formations.

[0005] With the advancement of computer technology and the improvement of computational theory, numerical simulation technology has become one of the mainstream methods for studying engineering problems. Traditional particle impact rock breaking simulations are mostly based on the finite element method and the finite difference method. However, in actual engineering, high-speed particles and high-speed drilling fluid form a complex two-phase flow system. Traditional single simulation methods cannot simulate the interaction between drilling fluid and impact particles, making it difficult to provide theoretical guidance for rock breaking process parameters. Summary of the Invention

[0006] To address the aforementioned problems, this invention proposes a simulation and optimization method and system for particle impact rock breaking technology. This invention overcomes the shortcomings of existing particle impact rock breaking simulation methods in characterizing parameters such as impact particle size distribution, drilling fluid flow rate, pipeline pressure, and particle volume fraction, thereby optimizing the particle impact rock breaking process and improving production efficiency.

[0007] According to some embodiments, the present invention adopts the following technical solution:

[0008] A simulation and optimization method for particle impact rock breaking technology includes the following steps:

[0009] Obtain spatial data of rock strata, obtain structural information of rock strata, and build a model of rock strata;

[0010] Obtain the macroscopic mechanical parameters of the rock sample at the bottom of the target well;

[0011] According to the particle size distribution curve, the particles are filled into the established rock layer model. The particles transfer force and torque between them through the parallel bonding model. Then, the parameters are calibrated according to the macroscopic mechanical parameters to make the strength index of the generated rock layer model consistent with the obtained rock sample.

[0012] A three-dimensional pipeline model was created based on the rock-breaking nozzles used at the work site.

[0013] Computational fluid dynamics was used to simulate the flow of drilling fluid in a three-dimensional pipe, and digital elevation model was used to simulate the flow of impact particles in the drilling fluid and their ejection onto the rock mass.

[0014] The degree of rock fragmentation is characterized by the fracture of parallel bond bonds in the rock strata model; the wear range of the pipe is represented by the stress distribution in the nozzle; and the blockage in the nozzle is represented by the particle accumulation position in the nozzle, thus obtaining the destructive effect of particle impact rock breaking technology on the rock mass under the current simulation parameters.

[0015] By changing the rock-breaking parameters and conducting multiple simulations, the response relationship between various rock-breaking parameters and simulation results is calculated. Based on the analysis results, an optimized scheme for particle impact rock-breaking technology suitable for actual operating conditions is determined.

[0016] As an alternative implementation, the macroscopic mechanical parameters include several parameters among particle size distribution curve, uniaxial compressive strength, tensile strength, elastic modulus, Poisson's ratio, friction angle, cohesion, and friction coefficient.

[0017] As an alternative implementation method, the specific process of establishing a three-dimensional pipeline model includes establishing a three-dimensional model according to the same size ratio based on the nozzle used in the on-site drilling operation, and setting the length from the nozzle inlet to the outlet.

[0018] Fill the wall unit into the 3D model, and set the appropriate distance from the nozzle outlet to the rock mass based on the length from the nozzle inlet to the outlet.

[0019] As an alternative implementation method, computational fluid dynamics is used to simulate the flow of drilling fluid within a three-dimensional pipe, and a digital elevation model is used to simulate the flow of impact particles in the drilling fluid and their ejection onto the rock mass. Specifically, this includes:

[0020] Set the parameters and boundary conditions for the computational fluid dynamics-digital elevation model coupling;

[0021] Based on the spatial dimensions of the established three-dimensional pipeline model, appropriate fluid computation meshes are divided at the same spatial location within the pipeline to simulate the flow of drilling fluid within the pipeline.

[0022] Based on the parameters of the computational fluid dynamics-digital elevation model coupling, impact particles are generated at the pipe inlet according to the volume fraction. The generation position of the particles in the x-direction is set. The contact models between impact particles, between impact particles and the pipe wall, and between impact particles and rock strata are all set as linear contact models to simulate the physical process of impact particles in the rock breaking process.

[0023] Set the time step for the fluid computation domain and the time step for the digital elevation model computation domain, and perform calculations according to the set time steps until the total simulation time is met.

[0024] As a further step, the parameters include impact particle diameter, particle density, particle Poisson's ratio, particle static friction coefficient, particle rolling friction coefficient, particle generation rate, particle recovery coefficient, particle volume fraction, and pipe wall friction coefficient.

[0025] Boundary conditions include setting the inlet as a velocity boundary, the initial velocities of particles and drilling fluid, and the nozzle outlet as a pressure boundary, with an outlet pressure value.

[0026] As an alternative implementation method, the specific process of analyzing the simulation effect of particle impact rock breaking includes: recording the fracture of parallel bonds, and using the fracture of parallel bonds to represent the degree of rock mass fragmentation;

[0027] The stress distribution in the pipe and nozzle in the x, y, and z directions during the coupling process is obtained, and the stress magnitude in the pipe is used to represent the degree of pipe wear.

[0028] The simulation results show the damage effect of the rock strata and the wear degree of the three-dimensional high-pressure nozzle under the current simulation parameters.

[0029] As an alternative implementation method, the specific process of changing rock breaking parameters and conducting multiple simulations includes changing drilling fluid velocity, particle volume fraction, pipeline pressure and / or particle size, conducting multiple computational fluid dynamics-digital elevation model coupled simulations, obtaining simulation results of rock mass fragmentation degree, pipeline wear range and / or nozzle damage range under different rock breaking parameters, and obtaining the response relationship between rock breaking parameters and simulation results.

[0030] A particle impact rock breaking process simulation and optimization system includes:

[0031] The rock strata model building module is configured to acquire spatial data of rock strata, acquire structural surface information of rock strata, and build a model of rock strata.

[0032] The macroscopic mechanical parameter acquisition module is configured to acquire the macroscopic mechanical parameters of the rock sample at the bottom of the target well.

[0033] The parameter calibration module is configured to fill the established rock layer model with particles according to the particle size distribution curve. The particles transfer force and torque between them through the parallel bonding model. Then, the parameters are calibrated according to the macroscopic mechanical parameters so that the strength index of the generated rock layer model is consistent with the obtained rock sample.

[0034] The 3D pipeline model building module is configured to create a 3D pipeline model based on the rock-breaking jet pipe used at the work site.

[0035] The impact simulation module is configured to use computational fluid dynamics to simulate the flow of drilling fluid in a three-dimensional pipe, and to use a digital elevation model to simulate the flow of impact particles in the drilling fluid and the process of them being ejected onto the rock mass.

[0036] The calculation module is configured to characterize the degree of rock mass fracture based on the fracture of parallel bond bonds in the rock layer model; represent the wear range of the pipe based on the stress distribution in the nozzle; and represent the blockage in the nozzle based on the particle accumulation position in the nozzle, thereby obtaining the destructive effect of the particle impact rock breaking process on the rock mass under the current simulation parameters.

[0037] The scheme confirmation module is configured to change rock-breaking parameters, conduct multiple simulation processes, calculate the response relationship between various rock-breaking parameters and simulation results, and determine an optimized scheme for particle impact rock-breaking technology that is suitable for actual operating conditions based on the analysis results.

[0038] A computer-readable storage medium storing a plurality of instructions adapted for loading by a processor of a terminal device and executing steps in the method.

[0039] A terminal device includes a processor and a computer-readable storage medium, the processor being configured to implement instructions; the computer-readable storage medium being configured to store a plurality of instructions adapted to be loaded by the processor and executed in accordance with the steps of the method described therein.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0041] (1) Traditional rock strata modeling cannot accurately obtain information on structural surfaces such as joints and fissures in rock strata. This invention uses three-dimensional laser scanning technology and digital photogrammetry technology to obtain spatial data of working rock strata, which can obtain the real state of rock strata more accurately and realize high-precision modeling of rock strata.

[0042] (2) During the process of particle jet impact rock breaking, high-speed particles and high-speed fluid form a relatively complex two-phase flow. Traditional particle impact rock breaking simulation is mostly based on finite element method, finite difference method, etc. A single simulation calculation method cannot simulate the interaction between drilling fluid and impact particles. This invention is based on the CFD-DEM (Computational Fluid Dynamics-Digital Elevation Model) coupling method. CFD is used to simulate the flow of drilling fluid in a three-dimensional pipe, and DEM is used to simulate the flow of impact particles in drilling fluid and the process of being sprayed onto rock strata. This can more realistically reflect the physical process of particle impact rock breaking.

[0043] (3) The degree of rock mass fracture is represented by the fracture of parallel bond bonds, and the wear range of pipelines and nozzles is represented by the stress distribution. Based on the rock breaking parameters such as drilling fluid velocity, particle volume fraction, pipeline pressure, and particle size, multiple CFD-DEM coupled simulation calculations are carried out to obtain the corresponding relationship between rock breaking parameters and rock breaking effect, optimize the rock breaking process, and provide theoretical guidance for the field. Attached Figure Description

[0044] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0045] Figure 1 This is a flowchart of the high-speed particle impact rock breaking CFD-DEM simulation process of the present invention;

[0046] Figure 2 This is a schematic diagram of the calculation model of the present invention, wherein 1 is the nozzle model, 2 is the high-speed impact particle, 3 is the DEM rock mass model, and 4 is the fractured rock mass DEM particles. Detailed Implementation

[0047] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0048] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0049] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0050] like Figure 1 As shown, in one or more embodiments, a simulation optimization method for particle impact rock breaking process based on CFD-DEM coupling is disclosed, specifically including the following steps:

[0051] Step 1: Achieve high-precision modeling of the working rock strata based on 3D laser scanning technology and digital photogrammetry technology, specifically including the following steps:

[0052] Step 1.1: Transport the 3D laser scanner and digital photogrammetry instrument to the bottom of the working well to perform a 3D scan of the working surface of the rock strata at the bottom of the well, and obtain information on the structural surfaces of the rock strata such as joints and fissures;

[0053] Step 1.2: Import the acquired working rock strata spatial data into SolidWorks software to build a high-precision three-dimensional model of the rock strata;

[0054] Step 1.3: Import the completed 3D rock strata model into the DEM discrete element software, and then fill in the particles;

[0055] Step 2: Obtain rock samples from the bottom of the working well and conduct indoor rock mechanics experiments to obtain the macroscopic mechanical parameters of the working rock strata. This includes the following steps:

[0056] Step 2.1: Drill 7-9 sets of rock samples using a drilling machine and transport them to the laboratory for indoor rock mechanics experiments;

[0057] Step 2.2: The obtained rock samples were subjected to sieve analysis in the laboratory to obtain the particle size distribution curve of the rock samples. Then, the rock samples were made into standard samples and subjected to uniaxial compression test, Brazilian splitting test, and triaxial compression test to obtain the Poisson's coefficient ε, uniaxial compressive strength UCS, elastic modulus E, tensile strength tn, and friction angle of the rock samples. Macroscopic mechanical parameters such as cohesive force θ and friction coefficient υ;

[0058] Step 3: Fill the rock 3D model with particles in the DEM software and perform DEM discrete element parameter calibration, which includes the following steps:

[0059] Step 3.1: Based on the particle size distribution curve of the rock sample obtained in Step 2, fill the particles into the three-dimensional rock model according to the particle size distribution curve. The particles transfer force and torque between them through the parallel bonding model. Then, DEM parameter calibration is carried out according to the macroscopic mechanical physical parameters to make the strength index of the generated rock model consistent with the obtained rock sample.

[0060] Step 3.2: Based on the Poisson's ratio ε, uniaxial compressive strength UCS, Young's modulus E, tensile strength ten, and friction angle obtained in Step 2... Macroscopic mechanical parameters such as cohesion θ and friction coefficient υ were used to perform DEM parameter calibration to obtain parameters of the parallel bond model, including elastic modulus E. p Normal bond strength δ p Tangential bond strength τ p Normal stiffness k n Tangential stiffness k s The ratio of normal stiffness to tangential stiffness k n / s This ensures that the strength indices of the DEM rock model generated according to the parallel bonding model are consistent with those on-site.

[0061] Step 4: Create a 3D model of the nozzle in SolidWorks, import the model into DEM software, and then fill the model with wall elements. This includes the following steps:

[0062] Step 4.1: Based on the nozzle used in the on-site drilling operation, create a 3D model in SolidWorks with the same size ratio. Set the length from the nozzle inlet to the outlet as L. R ;

[0063] Step 4.2: Import the 3D nozzle model into the DEM software, then fill the model with wall elements. The distance L from the nozzle outlet to the rock mass... p For L R / 10;

[0064] Step 5: Conduct CFD-DEM coupled simulation. CFD is used to simulate the flow of drilling fluid within the 3D pipeline, and DEM is used to simulate the flow of impact particles in the drilling fluid and their ejection onto the rock mass. This includes the following steps:

[0065] Step 5.1: Set the parameters and boundary conditions for CFD-DEM coupling. Initial values ​​include the impact particle diameter d and particle density ρ. p Particle Poisson's ratio γ p Particle static friction system μ r Coefficient of rolling friction of particles μ s Particle formation rate v s Particle recovery coefficient μ j Particle volume fraction ωp 、Friction coefficient μ of the pipeline wall t The boundary conditions are set as follows: The inlet is set as a velocity boundary, and the initial velocities of both the particles and the drilling fluid are v1. The outlet of the nozzle is set as a pressure boundary, and the outlet pressure is set as P1.

[0066] Step 5.2: Generate the fluid domain

[0067] According to the spatial dimensions of the established three-dimensional pipeline model, appropriate fluid calculation grids are divided at the same spatial positions of the pipeline for simulating the flow of the drilling fluid in the pipeline.

[0068] Step 5.3: Generate impact particles

[0069] In the DEM software, according to the particle parameters set in Step 5.1, including particle diameter d, particle density ρ p , particle Poisson's ratio γ p , particle static friction coefficient μ r , particle rolling friction coefficient μ s , particle restitution coefficient μ j , particle generation rate v s , particle volume fraction ω p etc., impact particles are generated at the pipeline inlet according to the volume fraction. The generation position of the particles in the x direction is set as 0 < x < 10d. The contact models between impact particles, between impact particles and the pipeline wall, and between impact particles and the rock formation are all set as linear contact models for simulating the physical process of impact particles in the rock-breaking process.

[0070] Step 5.4: CFD-DEM coupled calculation

[0071] The time step of the fluid calculation domain is set as Δt1, and the time step of the DEM calculation domain is set as Δt2, and the DEM time step Δt2 < Δt1. The total simulation time is set as T, and the CFD-DEM simulation calculation is carried out. When t > T, the calculation is stopped.

[0072] Step 6: Analyze the simulation effect of particle impact rock breaking, specifically as follows:

[0073] Step 6.1: In the DEM software, use the built-in language of the DEM software to record the rupture situation of the parallel bond bonds, and represent the degree of rock mass fragmentation by the rupture situation of the parallel bond bonds.

[0074] Step6.2: In the DEM software, use the post-processing function to obtain the stress distribution in the x, y, and z directions of the pipeline and nozzle during the CFD-DEM coupling process, and represent the wear degree of the pipeline by the stress magnitude in the pipeline;

[0075] Step 6.3: Use post-processing software to obtain the damage effect of the rock strata and the wear degree of the three-dimensional high-pressure nozzle under the current simulation parameters.

[0076] Step 7: Change the rock breaking parameters such as drilling fluid velocity, particle volume fraction, pipeline pressure, and particle size, and conduct multiple CFD-DEM coupled simulation calculations to obtain simulation results such as the degree of rock mass fragmentation, pipeline wear range, and nozzle damage range under different rock breaking parameters, and obtain the response relationship between the rock breaking parameters and the simulation results.

[0077] Step 8: Based on the analysis results, obtain an optimized scheme for particle impact rock breaking technology that is suitable for actual operating conditions, and provide guidance for actual field operations.

[0078] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can 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, etc.) containing computer-usable program code.

[0079] This 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 block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can 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, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0080] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0081] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0082] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0083] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A simulation and optimization method for particle impact rock breaking technology, characterized in that, Includes the following steps: Obtain spatial data of rock strata, obtain structural information of rock strata, and build a model of rock strata; Obtain the macroscopic mechanical parameters of the rock sample at the bottom of the target well; According to the particle size distribution curve, the particles are filled into the established rock layer model. The particles transfer force and torque between them through the parallel bonding model. Then, the parameters are calibrated according to the macroscopic mechanical parameters to make the strength index of the generated rock layer model consistent with the obtained rock sample. A three-dimensional pipeline model was created based on the rock-breaking nozzles used at the work site. Computational fluid dynamics was used to simulate the flow of drilling fluid in a three-dimensional pipe, and digital elevation model was used to simulate the flow of impact particles in the drilling fluid and their ejection onto the rock mass. The degree of rock fragmentation is characterized by the fracture of parallel bond bonds in the rock strata model; the wear range of the pipe is represented by the stress distribution in the nozzle; and the blockage in the nozzle is represented by the particle accumulation position in the nozzle, thus obtaining the destructive effect of particle impact rock breaking technology on the rock mass under the current simulation parameters. By changing the rock-breaking parameters and conducting multiple simulations, the response relationship between various rock-breaking parameters and simulation results is calculated. Based on the analysis results, an optimized scheme for particle impact rock-breaking technology suitable for actual operating conditions is determined. Computational fluid dynamics was used to simulate the flow of drilling fluid within a three-dimensional pipe, and digital elevation modeling was used to simulate the flow of impact particles in the drilling fluid and their ejection onto the rock mass. Specifically, this included: Set the parameters and boundary conditions for the computational fluid dynamics-digital elevation model coupling; Based on the spatial dimensions of the established three-dimensional pipeline model, appropriate fluid computation meshes are divided at the same spatial location within the pipeline to simulate the flow of drilling fluid within the pipeline. Based on the parameters of the computational fluid dynamics-digital elevation model coupling, impact particles are generated at the pipe inlet according to the volume fraction. The generation position of the particles in the x-direction is set. The contact models are set between impact particles, between impact particles and the pipe wall, and between impact particles and rock strata to simulate the physical process of impact particles in rock breaking. Set the time step for the fluid computation domain and the time step for the digital elevation model computation domain, and perform calculations according to the set time steps until the total simulation time is met.

2. The particle impact rock breaking process simulation and optimization method as described in claim 1, characterized in that, The macroscopic mechanical parameters include several parameters from particle size distribution curve, uniaxial compressive strength, tensile strength, elastic modulus, Poisson's ratio, friction angle, cohesion, and friction coefficient.

3. The particle impact rock breaking process simulation and optimization method as described in claim 1, characterized in that, The specific process of establishing a three-dimensional pipeline model includes establishing a three-dimensional model based on the nozzles used in the on-site drilling operation, according to the same size ratio, and setting the length from the nozzle inlet to the outlet. Fill the wall unit into the 3D model, and set the appropriate distance from the nozzle outlet to the rock mass based on the length from the nozzle inlet to the outlet.

4. The particle impact rock breaking process simulation and optimization method as described in claim 1, characterized in that, The parameters include impact particle diameter, particle density, particle Poisson's ratio, particle static friction coefficient, particle rolling friction coefficient, particle generation rate, particle recovery coefficient, particle volume fraction, and pipe wall friction coefficient.

5. The particle impact rock breaking process simulation and optimization method as described in claim 1, characterized in that, The specific process of analyzing the simulation effect of particle impact rock breaking includes: recording the fracture of parallel bonds, and using the fracture of parallel bonds to represent the degree of rock mass fragmentation; The stress distribution in the pipe and nozzle in the x, y, and z directions during the coupling process is obtained, and the stress magnitude in the pipe is used to represent the degree of pipe wear. The simulation results show the damage effect of the rock strata and the wear degree of the three-dimensional high-pressure nozzle under the current simulation parameters.

6. The particle impact rock breaking process simulation and optimization method as described in claim 1, characterized in that, The specific process of changing rock-breaking parameters and conducting multiple simulations includes changing drilling fluid velocity, particle volume fraction, pipeline pressure and / or particle size, conducting multiple computational fluid dynamics-digital elevation model coupled simulations, obtaining simulation results of rock mass fragmentation degree, pipeline wear range and / or nozzle damage range under different rock-breaking parameters, and obtaining the response relationship between rock-breaking parameters and simulation results.

7. A particle impact rock breaking process simulation and optimization system, characterized in that, include: The rock strata model building module is configured to acquire spatial data of rock strata, acquire structural surface information of rock strata, and build a model of rock strata. The macroscopic mechanical parameter acquisition module is configured to acquire the macroscopic mechanical parameters of the rock sample at the bottom of the target well. The parameter calibration module is configured to fill the established rock layer model with particles according to the particle size distribution curve. The particles transfer force and torque between them through the parallel bonding model. Then, the parameters are calibrated according to the macroscopic mechanical parameters so that the strength index of the generated rock layer model is consistent with the obtained rock sample. The 3D pipeline model building module is configured to create a 3D pipeline model based on the rock-breaking jet pipe used at the work site. The impact simulation module is configured to use computational fluid dynamics to simulate the flow of drilling fluid in a three-dimensional pipe, and to use a digital elevation model to simulate the flow of impact particles in the drilling fluid and the process of them being ejected onto the rock mass. The calculation module is configured to characterize the degree of rock mass fracture based on the fracture of parallel bond bonds in the rock layer model; represent the wear range of the pipe based on the stress distribution in the nozzle; and represent the blockage in the nozzle based on the particle accumulation position in the nozzle, thereby obtaining the destructive effect of the particle impact rock breaking process on the rock mass under the current simulation parameters. The scheme confirmation module is configured to change the rock breaking parameters, conduct multiple simulation processes, calculate the response relationship between various rock breaking parameters and simulation results, and determine the particle impact rock breaking process optimization scheme that is suitable for actual operating conditions based on the analysis results. Computational fluid dynamics was used to simulate the flow of drilling fluid within a three-dimensional pipe, and digital elevation modeling was used to simulate the flow of impact particles in the drilling fluid and their ejection onto the rock mass. Specifically, this included: Set the parameters and boundary conditions for the computational fluid dynamics-digital elevation model coupling; Based on the spatial dimensions of the established three-dimensional pipeline model, appropriate fluid computation meshes are divided at the same spatial location within the pipeline to simulate the flow of drilling fluid within the pipeline. Based on the parameters of the computational fluid dynamics-digital elevation model coupling, impact particles are generated at the pipe inlet according to the volume fraction. The generation position of the particles in the x-direction is set. The contact models are set between impact particles, between impact particles and the pipe wall, and between impact particles and rock strata to simulate the physical process of impact particles in rock breaking. Set the time step for the fluid computation domain and the time step for the digital elevation model computation domain, and perform calculations according to the set time steps until the total simulation time is met.

8. A computer-readable storage medium, characterized in that, It stores multiple instructions adapted for loading by the processor of a terminal device and executing the steps of the method according to any one of claims 1-6.

9. A terminal device, characterized in that, It includes a processor and a computer-readable storage medium, the processor being used to implement various instructions; the computer-readable storage medium being used to store a plurality of instructions adapted to be loaded by the processor and executed in the steps of the method of any one of claims 1-6.

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