Drilling fluid solid-phase invasion damage evaluation method, device, medium and equipment

Abstract

The present invention relates to a method, device, medium and equipment for evaluating the damage caused by the invasion of solid phase in drilling fluid. The method comprises the following steps: S1. Obtain the core of the target interval of the adjacent well, cut and grind it into a cast thin section, and reconstruct the physical model of the pore structure of the porous medium according to the image of the cast thin section; S2. Obtain the drilling fluid of the target interval of the well being drilled, extract the solid particles in the drilling fluid and analyze their properties, and then conduct tests on the physical and chemical properties of the drilling fluid to obtain test parameters; S3. Establish a numerical simulation model for the invasion of drilling fluid, and evaluate the degree of damage caused by the invasion of solid phase according to the change in permeability and the distribution of retained / plugged solid particles before and after the invasion of drilling fluid to obtain a judgment result; S4. Judge whether the drilling fluid formula is suitable for drilling operations according to the judgment result; if not, optimize the design of the drilling fluid until a reasonable drilling fluid formula is selected.

Description

Technical Field

[0001] The present invention relates to a method, device, medium and equipment for evaluating the damage caused by the invasion of solid phase in drilling fluid, belonging to the technical field of petroleum and natural gas reservoir protection. Background Art

[0002] With the drilling of the formation, the original balance of the formation is broken. Under the action of positive pressure difference, the solid particles in the drilling fluid inevitably invade the formation, changing the permeability of the formation. For various solid particles, some are necessary components of the drilling fluid, and some are harmful solids that have not been removed. After they invade the oil and gas reservoir, they will inevitably deposit and bridge at the throats of the reservoir, or be adsorbed on the wall surface of the porous medium, resulting in the narrowing of the pore seepage channels and even blocking the throats. This behavior can cause 10% - 100% damage to the oil and gas reservoir. Therefore, it is extremely important to quantitatively and rapidly evaluate the degree of damage caused by the invasion of solid particles in drilling fluid and the reasons for the damage.

[0003] In the damage caused by solid phase invasion, predecessors often carried out according to SY / T:6540 - 2002 "Indoor Evaluation Method for Damage of Drilling Fluid and Completion Fluid to Oil Reservoirs", but limited by experimental instruments, the quantification is poor, the timeliness is poor, and the visualization degree is poor. Summary of the Invention

[0004] Aiming at the above technical problems, the present invention provides a method, device, medium and equipment for evaluating the damage caused by the invasion of solid phase in drilling fluid. This method can simulate the numerical value of the damage caused by the invasion of solid phase in drilling fluid in complex porous media, intuitively, quickly, economically and quantitatively evaluate the degree of damage, and form a rapid optimization scheme for drilling fluid.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for evaluating the damage caused by the invasion of solid phase in drilling fluid, comprising the following steps:

[0007] S1. Obtain the core of the target interval of the adjacent well and cut and grind it into a cast thin section, and reconstruct the physical model of the pore structure of the porous medium according to the image of the cast thin section;

[0008] S2. Obtain the drilling fluid of the target interval of the well being drilled, extract the solid particles in the drilling fluid and analyze their geometric properties and physical properties, and then test the physical and chemical properties of the drilling fluid to obtain test parameters;

[0009] S3. Based on the lattice Boltzmann method - discrete element method, establish a numerical simulation model for the invasion of drilling fluid according to the test parameters, the physical model of the pore structure of the porous medium and in combination with drilling engineering parameters, and evaluate the degree of damage caused by the invasion of solid phase according to the change of permeability before and after the invasion of drilling fluid and the distribution of retained / plugged solid particles to obtain a determination result;

[0010] S4. When the determination result shows that the damage degree of reservoir solid-phase invasion is weak, use this drilling fluid formula for drilling operations; when the damage degree of solid-phase invasion is strong, optimize the particle size ratio of solid particles and the formula of drilling fluid base slurry according to its plugging degree and retention degree, and repeat step S3 until a reasonable drilling fluid formula is selected.

[0011] For the evaluation method of drilling fluid solid-phase invasion damage, preferably, the step S1 includes the following specific steps:

[0012] S11. Observe the cast thin section through an optical microscope and obtain its image;

[0013] S12. Based on the gray processing result, identify the pores and mineral particles in the cast thin section. For a certain elevation value of the pores, assign 0 elevation to the mineral particles, and reconstruct the physical model of the pore structure of the real porous medium;

[0014] S13. Manually process some dead pores and extremely narrow throats in the physical model of the porous medium pore structure, including deleting pores or connecting pores.

[0015] For the evaluation method of drilling fluid solid-phase invasion damage, preferably, the step S2 includes the following specific steps:

[0016] S21. The geometric properties of solid particles include particle size distribution and shape;

[0017] S22. The physical properties of solid particles are set according to their material composition;

[0018] S23. The physical properties of drilling fluid include kinematic viscosity and density;

[0019] S24. The chemical properties of drilling fluid include the potential energy of solid particles and the ionic strength of drilling fluid.

[0020] For the evaluation method of drilling fluid solid-phase invasion damage, preferably, the particle size in the step S21 is measured by a laser particle size analyzer, and the particle shape is measured by an optical microscope;

[0021] The kinematic viscosity in the step S23 is measured by a six-speed viscometer;

[0022] The potential energy of solid particles in the step S24 is measured by a Zeta potentiometer, and the ionic strength of drilling fluid is measured by an ion concentration meter.

[0023] For the evaluation method of drilling fluid solid-phase invasion damage, preferably, the step S3 includes the following specific steps:

[0024] S31. Establish a numerical simulation model of drilling fluid invasion based on the lattice Boltzmann method - discrete element method. The expression of the contact force model received by particles during the calculation process is:

[0025]

[0026]

[0027] Among them, m i is the particle mass; I i is the moment of inertia; t is the time step; v i and w i are the translational velocity and angular velocity of particle i; and M ij are the contact force and torque between particles i-j or between the particle and the porous medium wall; is the non-contact force between particles i-j; F i f The interaction force between particle i and the fluid; F i g is the gravity;

[0028] S32. The van der Waals force and the double-layer repulsion force are the key factors affecting the adsorption and retention of solid particles in the drilling fluid. The sum of their potential energies is called the DLVO potential energy, which is expressed as:

[0029] Υ(h) = (1 - c)Υ(h + h r ) + cΥ(h)

[0030] In the formula, Υ is the DLVO potential energy; h is the distance between the solid particle and the top of the skeleton; h r is the roughness height; c is the density of the nanocolumns on the surface of the skeleton;

[0031] S33. When dealing with the interaction between the drilling fluid flow and the solid particles, the immersed boundary method is adopted:

[0032]

[0033] In the formula: f i (x + c i Δt, t + Δt) is the velocity distribution function of the particle at position x moving to the adjacent node at the discrete velocity c within the time step Δt and colliding with other particles; f i (x, Δt) is the velocity distribution function of the particle at position x within the time step Δt; c i is the discrete lattice velocity; f i (x, t) is the density distribution function of the fluid node moving at position x, time t, and velocity c i ; τ i BGK is the relaxation time; Δt is the step size; f i en i (x, t) is f i(x,t) local equilibrium distribution function; is the additional collision term for overlapping nodes with the solid; B s is related to ε s weight coefficient; ε s is the percentage of solid content in the lattice;

[0034] S34. One of the evaluation indexes for the solid phase invasion damage degree of drilling fluid is the permeability damage rate, and its calculation formula is:

[0035]

[0036] In the formula, Pr is the permeability damage rate; the permeability without particle injection is K i ; the permeability after the invasion of solid phase particles is K t .

[0037] The permeability K is solved according to Darcy's law and is expressed as:

[0038]

[0039] In the formula, v is the inlet end inflow velocity; ΔP is the pressure difference between the inlet and outlet; μ is the fluid viscosity; L is the length of the simulation area; H is the width of the simulation area;

[0040] S35. One of the evaluation indexes for the solid phase invasion damage degree of drilling fluid is the distribution of plugged / retained solid phase particles. It is identified by tracking the images of the invasion process of solid phase particles, and the plugged particles caused by bridging and the retained particles caused by adsorption, sedimentation, etc. are distinguished, and the area ratio is statistically calculated.

[0041] In the described method for evaluating the solid phase invasion damage of drilling fluid, preferably, the step S4 includes the following specific steps:

[0042] S41. When the solid phase invasion damage degree of the drilling fluid is weak, the current formulation is used for drilling operations;

[0043] S42. When the solid phase invasion damage degree of the drilling fluid is strong, the proportion of solid phase particles caused by adsorption and retention is relatively high, then the base slurry formulation is optimized according to the chemical properties of the drilling fluid; when the proportion of solid phase particles caused by plugging is relatively high, then the particle size ratio of the solid phase particles is optimized.

[0044] The second aspect of the present invention provides a device for evaluating the solid phase invasion damage of drilling fluid, including:

[0045] The first processing unit is used to obtain the core of the target interval of the adjacent well, cut and grind it into a cast thin section, and reconstruct the physical model of the pore structure of the porous medium according to the image of the cast thin section;

[0046] A second processing unit, configured to obtain the drilling fluid in the target interval of the well being drilled, extract the solid particles in the drilling fluid and analyze their geometric properties and physical properties, and then conduct tests on the physical and chemical properties of the drilling fluid to obtain test parameters;

[0047] A third processing unit, configured to establish a numerical simulation model of drilling fluid invasion based on the lattice Boltzmann method - discrete element method according to the test parameters, the physical model of the pore structure of the porous medium, and in combination with the drilling engineering parameters, and evaluate the degree of solid phase invasion damage based on the permeability change before and after drilling fluid invasion and the distribution of retained / plugged solid particles, to obtain a determination result;

[0048] A fourth processing unit, configured to determine that when the determination result shows that the degree of solid phase invasion damage to the reservoir is weak, the drilling fluid formulation is used for drilling operations; when the degree of solid phase invasion damage is strong, the particle size ratio of the solid particles and the drilling fluid base slurry formulation are optimized specifically according to the degree of blockage and retention, and the steps of the third processing unit are repeated until a reasonable drilling fluid formulation is optimized.

[0049] A third aspect of the present invention provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above-mentioned method for evaluating the damage of solid phase invasion of drilling fluid are implemented.

[0050] A fourth aspect of the present invention provides a computer device, including a memory, a processor, and a computer program stored on the memory and executable on the processor, and when the processor executes the computer program, the steps of the above-mentioned method for evaluating the damage of solid phase invasion of drilling fluid are implemented.

[0051] Due to the above technical solutions adopted by the present invention, it has the following advantages:

[0052] 1. The method for evaluating the damage of solid phase invasion of drilling fluid based on the LBM-DEM coupling model proposed by the present invention can intuitively, quickly, economically and quantitatively evaluate the degree of damage and damage mechanism of solid particles in drilling fluid to the reservoir.

[0053] 2. The evaluation method of the present invention takes into account factors such as van der Waals force, electrostatic force, particle contact force, and fluid-particle interaction force between particles, and can specifically evaluate and optimize the drilling fluid formulation from both physical and chemical aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a numerical simulation flow chart of the method for evaluating the damage of solid phase invasion of drilling fluid provided by an embodiment of the present invention;

[0055] Figure 2 a is a reconstructed diagram of the porous medium provided by this embodiment of the present invention, Figure 2 b is Figure 2 a partial enlarged view of a;

[0056] Figure 3 The graph of the decline rate of permeability provided by this embodiment of the present invention;

[0057] Figure 4 The simulation diagram of solid particle invasion provided by this embodiment of the present invention;

[0058] Figure 5 The optimized simulation diagram of solid particle invasion provided by this embodiment of the present invention. Detailed implementation manners

[0059] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0060] In view of the problems that the existing laboratory evaluation methods for the damage of drilling and completion fluids to oil reservoirs are limited by experimental instruments, with poor quantification, poor timeliness, and poor visualization, the present invention proposes a method for evaluating the damage of solid-phase invasion of drilling fluids based on the LBM-DEM coupling model. This method can visually, quantitatively, quickly, and economically evaluate the damage degree and damage causes of solid particles in drilling fluids to reservoir porous media, and form an optimized drilling fluid formulation plan accordingly.

[0061] As Figure 1 shown, the method for evaluating the damage of solid-phase invasion of drilling fluids involved in the present invention includes the following steps:

[0062] S1. Obtain the core of the target interval of the adjacent well and cut and grind it into a cast thin section, and reconstruct the physical model of the pore structure of the porous medium according to the image of the cast thin section;

[0063] S2. Obtain the drilling fluid of the target interval of the well being drilled, extract the solid particles in the drilling fluid and analyze their geometric and physical properties, and then conduct tests on the physical and chemical properties of the drilling fluid to obtain test parameters;

[0064] S3. Based on the test parameters, the physical model of the pore structure of the porous medium, and in combination with drilling engineering parameters (bottom hole pressure, formation pressure, etc.), establish a numerical simulation model for drilling fluid invasion based on the lattice Boltzmann method - discrete element method, and evaluate the degree of solid-phase invasion damage according to the permeability change and the distribution of retained / plugged solid particles before and after drilling fluid invasion to obtain a judgment result;

[0065] S4. When the determination result shows that the degree of reservoir solid-phase invasion damage is weak, use this drilling fluid formula for drilling operations; when the degree of solid-phase invasion damage is strong, optimize the particle size ratio of solid particles and the formula of the drilling fluid base slurry according to its blockage degree and retention degree, and repeat step S3 until a reasonable drilling fluid formula is selected.

[0066] Further, the specific steps of step S1 include the following:

[0067] S11. Observe the cast thin section through an optical microscope and obtain its image;

[0068] S12. Based on the gray-scale processing result, identify the pores and mineral particles in the cast thin section. For a certain elevation value of the pores, assign 0 elevation to the mineral particles, and reconstruct the physical model of the pore structure of the real porous medium;

[0069] S13. Manually process some dead pores and extremely narrow throats in the physical model of the porous medium pore structure, including deleting pores or connecting pores.

[0070] For the above-mentioned method for evaluating the damage of drilling fluid solid-phase invasion, preferably, the specific steps of step S2 include the following:

[0071] S21. The geometric properties of solid particles include particle size distribution and shape;

[0072] S22. The physical properties of solid particles are set according to their material composition;

[0073] S23. The physical properties of the drilling fluid include kinematic viscosity and density;

[0074] S24. The chemical properties of the drilling fluid include the potential energy of solid particles and the ionic strength of the drilling fluid.

[0075] Further, the particle size in step S21 is measured by a laser particle size analyzer, and the particle shape is measured by an optical microscope;

[0076] The kinematic viscosity in step S23 is measured by a six-speed viscometer;

[0077] The potential energy of solid particles in step S24 is measured by a Zeta potentiometer, and the ionic strength of the drilling fluid is measured by an ion concentration meter.

[0078] Further, the specific steps of step S3 include the following:

[0079] S31. Establish a numerical simulation model of drilling fluid invasion based on the lattice Boltzmann method - discrete element method (LBM-DEM). The expression of the contact force model of particles during the calculation process is:

[0080]

[0081] Among them, m i is the particle mass; I i is the moment of inertia; t is the time step; v i and w i are the translational and angular velocities of particle i; and M ij is the contact force and torque between particles ij or between particles and the porous medium wall; is the non-contact force between particles ij; F i f The interaction force between particle i and fluid; F i g is gravity;

[0082] S32, van der Waals force and double layer repulsion are the key factors affecting the adsorption and retention of solid particles in drilling fluid. The sum of their potential energies is called DLVO potential energy, which is expressed as:

[0083] Υ(h)=(1-c)Υ(h+h r )+cΥ(h) (2)

[0084] Where Υ is the DLVO potential energy; h is the distance between the solid particles and the top of the skeleton; h r is the roughness height; c is the density of nanopillars on the skeleton surface;

[0085] S33. When dealing with the interaction between drilling fluid flow and solid particles, the immersed boundary method (IB) is used to calculate:

[0086]

[0087] Where: f i (x+c i Δt,t+Δt) is the particle at position x with a discrete velocity c within the time step Δt. i The velocity distribution function after moving to the adjacent node and colliding with other particles; f i (x, Δt) is the particle velocity distribution function at position x within the time step Δt; c i is the discrete point velocity; f i (x, t) is the position of the fluid node at x, time t, and velocity c i Moving density distribution function; τ BGK is the relaxation time; Δt is the step length; f i en (x,t) is f i The local equilibrium distribution function of (x,t); B is the additional collision item for nodes overlapping with the entity; s For s Related weight coefficient; εs is the percentage of the solid content in the lattice;

[0088]

[0089] where: ε s is the proportion of solid-phase particles; f -i (x, t) and f i (x, t) are the particle velocity distribution functions at position x within time t, and ±i are the positive (negative) directions; f i en (ρ, v p ) and are the local equilibrium functions related to the fluid density ρ, the fluid velocity u, and the particle velocity v p ;

[0090] Furthermore, ε of the fluid node s is 0; ε inside the solid-phase particles s is 1; the value of ε s between 0 and 1 indicates that the node is located on the surface of the solid-phase particles;

[0091] Furthermore, the inlet and outlet are constant-pressure boundaries, and the upper and lower are no-slip boundaries;

[0092] S34. One of the evaluation indexes for the damage degree of solid-phase invasion of drilling fluid is the permeability damage rate, and its calculation formula is:

[0093]

[0094] where Pr is the permeability damage rate; the permeability without particle injection is K i ; the permeability after the invasion of solid-phase particles is K t .

[0095] Furthermore, the permeability K is solved according to Darcy's law and is expressed as:

[0096]

[0097] where v is the inlet-end inflow velocity; ΔP is the pressure difference between the inlet and outlet; μ is the fluid viscosity; L is the length of the simulation area; H is the width of the simulation area;

[0098] S35. One of the evaluation indexes for the damage degree of solid-phase invasion of drilling fluid is the distribution of blocked / stagnant solid-phase particles. It is identified by tracking the images of the solid-phase particle invasion process, and the blocked particles caused by bridging and the stagnant particles caused by adsorption, sedimentation, etc. are distinguished, and the area ratio is statistically calculated.

[0099] Furthermore, the step S4 includes the following specific steps:

[0100] S41. When the damage degree of solid phase invasion of the drilling fluid is weak, the current formulation is used for drilling operations;

[0101] S42. When the damage degree of solid phase invasion of the drilling fluid is strong and the proportion of solid phase particles caused by adsorption and retention is relatively high, the base slurry formulation is optimized according to the chemical properties of the drilling fluid; when the proportion of solid phase particles caused by plugging is relatively high, the particle size ratio of solid phase particles is optimized.

[0102] The implementation scheme of the present invention will be described in detail below with specific application examples.

[0103] The evaluation method for solid phase invasion damage of drilling fluid based on the LBM-DEM coupling model has the following specific calculation steps:

[0104] S1. Determine the Guantao Formation of Well Y7 in Offshore X Oilfield as the evaluation target layer, select the core of adjacent wells and cut and produce cast thin sections, and reconstruct the physical model of the pore structure of porous media in the quasi-two-dimensional state (as Figure 2 shown);

[0105] S2. According to the properties of solid phase particles and the physical and chemical properties of the base slurry in the drilling fluid in the study area, assign corresponding fluid and particle parameters (Table 1), assign pressure boundary conditions to the inlet and outlet, and use the LBM-DEM coupling method to simulate the damage degree of solid phase invasion of this drilling fluid formulation;

[0106] S3. After the simulation is completed, analyze. First, clarify the decline curve of the drilling fluid permeability and evaluate its permeability damage degree (as Figure 3 shown), and it is considered that for the current drilling fluid, its permeability damage exceeds 55%, and the damage degree is strong (SY / T: 6540-2002 "Indoor Evaluation Method for Drilling Fluid and Completion Fluid Damaging Oil Reservoirs"); then distinguish the particles caused by adsorption and retention and the particles caused by bridging and plugging, and it is considered that the main factor of its damage is that the effectiveness of pore throats becomes poor due to the adsorption of particles on the wall of porous media. Therefore, first consider optimizing the properties of the drilling fluid base slurry (as Figure 4 shown);

[0107] S4. Re-simulate the damage of solid phase invasion of the optimized drilling fluid formulation, and it is considered that the permeability damage degree of the drilling fluid drops to 36%, the particle adsorption and plugging are significantly reduced, and the reservoir damage is weak (as Figure 5 shown).

[0108] Table 1 Simulation basic parameters set according to the characteristics of loose sandstone drilling fluid in Bozhong X Oilfield

[0109]

[0110] The second aspect of the present invention provides an evaluation device for solid phase invasion damage of drilling fluid, including:

[0111] The first processing unit is used to obtain the core of the target layer section of the adjacent well and cut and grind it into a casting thin section, and reconstruct the physical model of the porous medium pore structure according to the image of the casting thin section;

[0112] The second processing unit is used to obtain the drilling fluid of the target layer being drilled, extract the solid phase particles in the drilling fluid and analyze their geometric properties and physical properties, and then test the physical and chemical properties of the drilling fluid to obtain test parameters;

[0113] The third processing unit is used to establish a drilling fluid invasion numerical simulation model based on the lattice Boltzmann method-discrete element method according to the test parameters, the physical model of the porous medium pore structure and the drilling engineering parameters, and evaluate the degree of solid phase invasion damage according to the permeability change before and after the drilling fluid invasion and the distribution of the retained / blocked solid phase particles to obtain the judgment result;

[0114] The fourth processing unit is used to determine that when the judgment result shows that the degree of solid phase invasion damage to the reservoir is relatively weak, the drilling fluid formula is used for drilling operations; when the degree of solid phase invasion damage is relatively strong, the solid phase particle size ratio and the drilling fluid base slurry formula are optimized according to the degree of blockage and retention, and the steps of the third processing unit are repeated until a reasonable drilling fluid formula is selected.

[0115] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the above-mentioned method for evaluating the damage caused by solid phase intrusion of drilling fluid.

[0116] A fourth aspect of the present invention provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned drilling fluid solid phase invasion damage assessment method when executing the computer program.

[0117] The present invention is described in terms of flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to specific embodiments. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0118] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce a manufacture including an instruction means that implements the functions specified in one or more of the processes Figure 1 one or more processes and / or blocks Figure 1 specified in the block or blocks.

[0119] These computer program instructions can 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, whereby the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in one or more of the processes Figure 1 one or more processes and / or blocks Figure 1 specified in the block or blocks.

[0120] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. However, such modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for evaluating the damage caused by solid phase invasion of drilling fluid, characterized in that, It includes the following steps: S1. Obtain the core of the target interval of the adjacent well, cut and polish it into a casting thin section, and reconstruct the physical model of the pore structure of the porous medium according to the image of the casting thin section; S2. Obtain the drilling fluid of the target interval of the well being drilled, extract the solid particles in the drilling fluid and analyze their geometric properties and physical properties, and then conduct tests on the physical and chemical properties of the drilling fluid to obtain test parameters; S3. Based on the test parameters, the physical model of the pore structure of the porous medium, and in combination with the drilling engineering parameters, establish a numerical simulation model of drilling fluid invasion based on the lattice Boltzmann method - discrete element method, and evaluate the degree of solid phase invasion damage according to the permeability change before and after drilling fluid invasion and the distribution of retained / plugged solid particles to obtain a judgment result; S4. When the judgment result shows that the degree of solid phase invasion damage to the reservoir is weak, use this drilling fluid formula for drilling operations; when the degree of solid phase invasion damage is strong, optimize the particle size ratio of solid particles and the formula of the drilling fluid base slurry according to the degree of blockage and retention, and repeat step S3 until a reasonable drilling fluid formula is selected.

2. The method for evaluating the damage caused by the invasion of drilling fluid solids according to claim 1, characterized in that, The step S1 includes the following specific steps: S11. Observe the casting thin section through an optical microscope and obtain its image; S12. Based on the gray processing result, identify the pores and mineral particles of the casting thin section, assign a certain elevation value to the pores, and assign 0 elevation to the mineral particles to reconstruct the physical model of the real porous medium pore structure; S13. Manually process some dead pores and extremely narrow throats in the physical model of the porous medium pore structure, including deleting pores or connecting pores.

3. The method for evaluating the damage caused by solid-phase invasion of drilling fluid according to claim 2, wherein, The step S2 includes the following specific steps: S21. The geometric properties of solid particles include particle size distribution and shape; S22. The physical properties of solid particles are set according to their material composition; S23. The physical properties of the drilling fluid include kinematic viscosity and density; S24. The chemical properties of the drilling fluid include the potential energy of solid particles and the ionic strength of the drilling fluid.

4. The method for evaluating the damage caused by the invasion of solid phase in drilling fluid according to claim 3, wherein, In the step S21, the particle size is measured by a laser particle size analyzer, and the particle shape is measured by an optical microscope; In the step S23, the kinematic viscosity is measured by a six-speed viscometer; In the step S24, the potential energy of solid particles is measured by a Zeta potentiometer, and the ionic strength of the drilling fluid is measured by an ion concentration meter.

5. The method for evaluating the damage caused by the invasion of solid phase of drilling fluid according to claim 4, characterized in that, The step S3 includes the following specific steps: S31. Establish a numerical simulation model of drilling fluid invasion based on the lattice Boltzmann method - discrete element method. The contact force model of particles during the calculation process is expressed as: where m i is the particle mass; I i is the moment of inertia; t is the time step; v i and w i are the translational velocity and angular velocity of particle i; and M ij are the contact force and torque between particles i-j or between the particle and the porous medium wall; is the non-contact force between particles i-j; F i f the interaction force between particle i and the fluid; F i g is the gravity; S32. The van der Waals force and the double-layer repulsive force are the key factors affecting the adsorption and retention of solid particles in the drilling fluid. The sum of their potential energies is called the DLVO potential energy, which is expressed as: Υ(h) = (1 - c)Υ(h + h r ) + cΥ(h) In the formula, Υ is the DLVO potential energy; h is the distance between the solid-phase particle and the top of the framework; h r is the roughness height; c is the density of the nanocolumns on the surface of the framework; S33. When dealing with the interaction between the flow of the drilling fluid and solid particles, the immersed boundary method is used: Where: f i (x+c i Δt,t+Δt) is the particle at position x with a discrete velocity c within the time step Δt. i The velocity distribution function after moving to the adjacent node and colliding with other particles; f i (x, Δt) is the particle velocity distribution function at position x within the time step Δt; c i is the discrete point velocity; f i (x, t) is the position of the fluid node at x, time t, and velocity c i Moving density distribution function; τ BGK is the relaxation time; Δt is the step length; f i en (x,t) is f i The local equilibrium distribution function of (x, t); Ω i S is the additional collision item for the nodes overlapping with the entity; B s For s Related weight coefficient; ε s is the percentage of solid content in the lattice; S34. One of the evaluation indexes of the degree of solid phase invasion damage of the drilling fluid is the permeability damage rate, and its calculation formula is: where Pr is the permeability damage rate; the permeability without particle injection is K i ; the permeability after solid-phase particle invasion is K t ; The permeability K is solved according to Darcy's law and is expressed as: In the formula, v is the inlet end inflow velocity; ΔP is the pressure difference between the inlet and outlet; μ is the fluid viscosity; L is the length of the simulation area; H is the width of the simulation area; S35. One of the evaluation indicators for the degree of solid phase invasion damage of drilling fluid is the distribution of blocked / retained solid phase particles. It uses images that track the solid phase particle invasion process for identification, and distinguishes between blocked particles caused by bridging and retained particles caused by adsorption, sedimentation, etc., and calculates their area share.

6. The method for evaluating the damage caused by the invasion of solid phase in drilling fluid according to claim 5, wherein, The step S4 comprises the following specific steps: S41. When the degree of solid phase invasion damage of the drilling fluid is relatively weak, the current formulation is used for drilling operations; S42. When the degree of solid phase intrusion damage of the drilling fluid is relatively high, and the proportion of solid phase particles caused by adsorption and retention is relatively high, the base slurry formula should be optimized according to the chemical properties of the drilling fluid; if the proportion of solid phase particles caused by blockage is relatively high, the particle size ratio of the solid phase particles should be optimized.

7. A device for evaluating the damage caused by the invasion of solid phase in drilling fluid, characterized in that, include: The first processing unit is used to obtain the core of the target layer section of the adjacent well and cut and grind it into a casting thin section, and reconstruct the physical model of the porous medium pore structure according to the image of the casting thin section; The second processing unit is used to obtain the drilling fluid of the target layer being drilled, extract the solid phase particles in the drilling fluid and analyze their geometric properties and physical properties, and then test the physical and chemical properties of the drilling fluid to obtain test parameters; The third processing unit is used to establish a drilling fluid invasion numerical simulation model based on the lattice Boltzmann method-discrete element method according to the test parameters, the physical model of the porous medium pore structure and the drilling engineering parameters, and evaluate the degree of solid phase invasion damage according to the permeability change before and after the drilling fluid invasion and the distribution of the retained / blocked solid phase particles to obtain the judgment result; The fourth processing unit is used to determine that when the judgment result shows that the degree of solid phase invasion damage to the reservoir is relatively weak, the drilling fluid formula is used for drilling operations; when the degree of solid phase invasion damage is relatively strong, the solid phase particle size ratio and the drilling fluid base slurry formula are optimized according to the degree of blockage and retention, and the steps of the third processing unit are repeated until a reasonable drilling fluid formula is selected.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, the steps of the method for evaluating drilling fluid solid phase invasion damage according to any one of claims 1 to 6 are implemented.

9. A computer device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the computer program, the steps of the method for evaluating drilling fluid solid phase invasion damage according to any one of claims 1 to 6 are implemented.

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