Numerical simulation method for equivalent amplification of columnar explosive during radial water coupling charging
Through the numerical simulation method of equivalently enlarged cylindrical explosives during radial water-coupled charging, the grid deformation problem caused by the difference in the diameter of the explosive roll and the distance to adjacent structures was solved, which saved computing time and storage memory and improved simulation accuracy.
Patent Information
- Application Number
- CN202510654281.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-21
- Publication Date
- 2025-10-17
AI Technical Summary
In the numerical simulation analysis, the diameter of the explosive roll differs by 3 to 4 orders of magnitude from the distance to the adjacent structures, resulting in problems such as overly small mesh division, deformed meshes, excessively long calculation times, and even inability to calculate.
The radial water-coupled charging method is adopted, and the explosion energy of a small-diameter high-detonation-velocity explosive charge is equivalently amplified to a large-diameter low-detonation-velocity explosive charge. The corresponding explosive detonation state equation is established to describe the explosion state and avoid deformed grids.
It reduces the computing time and storage memory consumption, and improves the efficiency and accuracy of numerical simulation.
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Figure CN120805385A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of numerical simulation analysis of blasting engineering, and particularly relates to a numerical simulation method for equivalent amplification of columnar explosive in radial water coupling charging. BACKGROUND
[0002] In the process of numerical simulation analysis of radial water coupling charging blasting, *MAT_HIGH_EXPLOSIVE_BURN (high explosive material) is generally used to simulate explosive explosion. When simulating the damage of seismic waves generated by explosive explosion to adjacent buildings in numerical calculation, the diameter of explosive roll is several centimeters, while the distance between the research object building and the explosive is tens of meters to hundreds of meters, and the difference between them is 3-4 orders of magnitude. The diameter of explosive roll is very small relative to the distance of adjacent buildings. When numerical modeling is carried out, the mesh of blast hole and explosive roll needs to be divided very small, which leads to the generation of distorted mesh, too long calculation time or even no result in numerical calculation.
[0003] Therefore, how to prevent the generation of distorted mesh in numerical calculation, save the computer calculation time and storage memory is a technical problem to be solved at present. SUMMARY
[0004] In order to solve the problems in the prior art, the present application provides a numerical simulation method for equivalent amplification of columnar explosive in radial water coupling charging, which uses the rule that the total energy released by small-diameter high-explosive-speed explosive charge in water coupling charging is equal to the total energy released by large-diameter low-explosive-speed explosive columnar charge, establishes the corresponding explosive detonation state equation after equivalent amplification, and thus the explosion state is well described, the modeling effect is good, no distorted mesh is generated, the calculation time is greatly reduced, and the storage memory is saved.
[0005] The embodiments of the present application provide the following schemes:
[0006] The embodiments of the present application provide a numerical simulation method for equivalent amplification of columnar explosive in radial water coupling charging, which comprises the following steps:
[0007] Step 1, selecting small-diameter high-explosive-speed columnar explosive charge for water coupling charging, the explosive density is ρ2, and the explosive speed is D;
[0008] Step 2, drawing the water shock wave P-v curve and the explosion product sparse wave P-v curve, and obtaining the shock wave front particle velocity v of the explosive-water interface from the intersection point of the two curves x and the shock wave front pressure P x ;
[0009] Step three, using the water column shock wave attenuation law, calculate the water column shock wave peak value at a certain point Further through the acoustic approximation theory to get the water shock wave acting on the initial pressure of the blast hole wall
[0010] Step four, after the shock wave continues through the water-rock interface and transmits into the rock, forming a transmitted stress wave in the rock, then propagates radially along the blast hole, calculate the peak stress σ at a distance r from the blast hole axis r ;
[0011] Step five, according to the principle of density reduction and detonation velocity, the small diameter high explosive charge is coupled and equivalent to large diameter low explosive charge, and the stress value in the rock after explosion is solved when σ r , that is, the large diameter low explosive detonation velocity;
[0012] Step six, the large diameter low explosive detonation velocity obtained by the above calculation is used as the condition to establish the explosive detonation state equation to simulate the detonation state of the coupled charge explosive.
[0013] In an alternative embodiment, when the small diameter high explosive charge of step one is water coupled, step two draws the water shock wave P-v curve by the following formula:
[0014]
[0015] Where P1 is the initial shock wave pressure in water, v w is the particle velocity of the water shock wave front; the rarefaction wave P-v curve in the explosion product is drawn by the following formula:
[0016]
[0017] Where P x and v x are the velocity at the interface between the detonation product and water.
[0018] In an alternative embodiment, when the small diameter high explosive charge of step one is water coupled, step two draws the water shock wave P-v curve by the following formula:
[0019]
[0020] Where P1 is the initial shock wave pressure in water, v w is the particle velocity of the water shock wave front; the rarefaction wave P-v curve in the explosion product is drawn by the following formula:
[0021]
[0022] where P x and v x are the velocities at the interface of the detonation products and water, respectively.
[0023] In an alternative embodiment, the initial pressure P0 is calculated by the following equation:
[0024]
[0025] where p0 is the undisturbed density of water, D w is the shock wave front velocity in water, p0D w is the shock impedance of the explosive, p m v m is the wave impedance of the rock.
[0026] In an alternative embodiment, the peak stress σ r at a distance r from the borehole axis is calculated by the following equation:
[0027]
[0028] where r c is the borehole radius, and a is the stress wave attenuation exponent, a = 2 - μ / (1 - μ), where μ is the Poisson's ratio of the rock.
[0029] In an alternative embodiment, the detonation velocity D3
[0030]
[0031] σ r = P m (29)
[0032] where P3 is the average initial pressure of the large-diameter low-velocity explosive, p3 is the density of the large-diameter low-velocity explosive, γ is the isentropic exponent of the explosive, P m is the initial pressure at the rock interface, p3D3 is the shock impedance of the small-diameter high-velocity explosive, p m v m is the wave impedance of the rock.
[0033] In an alternative embodiment, the equation of state of the explosive is described by the JWL equation, which is given by:
[0034]
[0035] where P is pressure, A, B, R1, R2 and ω are material constants related to explosives respectively; V is relative volume, E0 is initial specific internal energy, V CJ is the explosion volume of the explosive, and p is the density of the explosive, A=5.35545pV 2 , B=0.094983pV 2 , R1=4.2, R2=0.27R1, and ω=0.33,
[0036]
[0037] In an alternative embodiment, the explosive is rock emulsion explosive.
[0038] The present application has the beneficial effects of its technical solutions in that:
[0039] In numerical calculation, when simulating the damage of the seismic wave generated by explosive explosion to the adjacent building structure, the explosive roll diameter is several centimeters, and the distance between the research object building structure and the explosive is tens of meters to hundreds of meters, the difference in quantity between the two is 10 3 -10 4 times, the explosive roll diameter is very small relative to the distance of the adjacent building structure, and when numerical modeling is carried out, the mesh of the blast hole and the explosive roll needs to be divided very small, which leads to the generation of distorted mesh, too long calculation time or even no result in numerical calculation. In order to solve this problem, the present application provides a numerical simulation method for equivalent amplification of cylindrical explosive when radial water coupling charging, which uses the rule that the total energy released by the small-diameter high-explosive charge in water coupling charging is equal to the total energy released by the large-diameter low-explosive cylindrical charge, establishes the corresponding explosive detonation state equation after equivalent amplification, so as to well describe the explosion state, has good modeling effect, does not produce distorted mesh, can greatly reduce the calculation time and save storage memory. BRIEF DESCRIPTION OF DRAWINGS
[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.
[0041] Figure 1 The flowchart of the numerical simulation method for equivalent amplification of cylindrical explosive when radial water coupling charging provided by the present application is shown.
[0042] Figure 2 The schematic diagram of deep water water coupling charging of small-diameter high-explosive cylindrical charge is shown.
[0043] Figure 3It is a schematic diagram of physical quantity before and after shock wave.
[0044] Figure 4 It is a curve graph of detonation velocity attenuation of emulsion explosive in deep water.
[0045] Figure 5 It is a schematic diagram of graphical method of underwater shock wave in deep water.
[0046] Figure 6 It is a schematic diagram of shallow water coupling charge of small diameter high detonation velocity cylindrical explosive.
[0047] Figure 7 It is a schematic diagram of graphical method of underwater shock wave in shallow water.
[0048] Figure 8 It is a screenshot of modeling result of small diameter high detonation velocity explosive.
[0049] Figure 9 It is a screenshot of modeling result of large diameter low detonation velocity explosive.
[0050] Figure 10 It is a screenshot of time-consuming background data of small diameter high detonation velocity explosive.
[0051] Figure 11 It is a screenshot of time-consuming background data of large diameter low detonation velocity explosive.
[0052] Figure 12 It is a screenshot of memory occupation data of small diameter high detonation velocity explosive.
[0053] Figure 13 It is a screenshot of memory occupation data of large diameter low detonation velocity explosive. DETAILED DESCRIPTION
[0054] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art belong to the protection scope of the embodiments of the present application.
[0055] The present embodiment provides a numerical simulation method of equivalent amplification cylindrical explosive in radial water coupling charge, referring to Figure 1 , the method comprises:
[0056] Step one, select small diameter high detonation velocity cylindrical explosive water coupling charge, as Figure 2 shown, wherein the loaded explosive adopts rock emulsion explosive, and the explosive density is ρ2 and the detonation velocity is D.
[0057] Step two, draw the water shock wave P-v curve and the explosion product sparse wave P-v curve, get the shock wave front particle velocity v of the explosive-water interface from the intersection of the two curves x and shock wave front pressure P x The derivation process and principle of the two curves are as follows:
[0058] The physical quantities of the shock wave before and after the explosive-water interface are shown in Figure 3 , such as Figure 3 (1) shows that P0, p0, E0 and v0 are the pressure, density, internal energy and particle velocity of the undisturbed water medium; P1, p1, E1 and v1 are the pressure, density, internal energy and particle velocity of the water medium at the moment after the shock wave front passes; D is the shock wave velocity. When the explosive explodes in water, it satisfies the conservation of mass, momentum and energy. Taking the coordinates on the wave front, the mass flowing into the wave front from the right side per unit time is p0(D-v0), and the mass flowing out from the left side is p1(D-v1), as shown in Figure 3 (2).
[0059] According to the mass conservation, the mass of the medium flowing into the wave front from the right side per unit time is equal to the mass flowing out from the left side, that is:
[0060] m = p0(D-v0) = p1(D-v1) (1)
[0061] The change of momentum of the medium per unit time is m(v1-v0), and the impulse acting on the medium is P1-P0. According to the law of momentum conservation, during the propagation of the shock wave, the impulse acting on the medium per unit time is equal to the change of its momentum, so:
[0062] P1-P0 = m(v1-v0) = p0(D-v0)(v1-v0) (2)
[0063] The energy flowing into the wave front from the right side per unit time is composed of three parts: the internal energy mE0 of the medium, the kinetic energy of the medium and the work done by the pressure of the medium P0(D-v0). Similarly, the energy flowing out from the left side of the wave front is According to the law of energy conservation, the energy flowing into the wave front from the right side per unit time during the propagation of the shock wave should be equal to the energy flowing out from the left side of the wave front, that is:
[0064]
[0065] Substitute equations (1), (2) into equation (3) and arrange to get:
[0066]
[0067] The basic equation obtained by arranging equations (1), (2) and (4) is as follows:
[0068]
[0069] E1-E0 = 1 / 2(P1+P0)(1 / ρ0-1 / ρ1) (7)
[0070] To solve the above equations, the equation of state of water is needed. When the pressure range is greater than 2.5 x 10 3 MPa, the equation of state of water is the shock (Poisson) adiabatic equation:
[0071] (P+α) / P* = (ρ / ρ * ) k(s) (8)
[0072] In the formula, α = 529 MPa, ρ * = 2530 kg / m 3 , P* = 8940 MPa, and the index k(s) is a function of entropy s, which is a function of pressure and changes with the strength of the shock wave.
[0073] After the explosion of the explosive charge in water, the blast wave front will first impact the water at the edge of the charge and generate a water shock wave with a very high initial pressure. Generally, since the hole is filled with water, it can be approximately considered that the isentropic exponent of the detonation products does not change, and the pressure and density do not drop sharply. Therefore, it can be assumed that the detonation products expand according to the law of pV γ = const.
[0074] The detonation wave is vertically incident into the water from the explosive charge. In order to simplify the discussion of the problem, it is assumed that the entire process is one-dimensional and plane-symmetric, and the particle velocity of the explosive product at the interface between the explosive product and water is obtained:
[0075]
[0076] In the formula: γ is the adiabatic index of the detonation product, which is taken as 3 here; P x is the pressure at the interface between the detonation product and water; D is the detonation velocity of the explosive; and P L is the pressure on the blast wave front. After substituting the numerical values, we get:
[0077]
[0078] In the formula: v x is the velocity at the interface between the detonation product and water.
[0079] When v0 = 0, the particle velocity on the shock wave front in water is obtained from equation (5):
[0080]
[0081] According to the interface continuity condition, we know that:
[0082] P x =P1,v x =v1 (12)
[0083] Where: ρ1 and P1 are the density and pressure of the initial shock wave in water; ρ0 and P0 are the density and pressure of the undisturbed water medium.
[0084] According to the dynamics experiment, when the pressure 0<P1<4.5×10 4 MPa, the shock adiabatic equation in water is:
[0085]
[0086] Where D w and ν w are the shock wave front velocity and particle motion velocity in water, respectively, in m / s. The momentum equation of the shock wave in water is:
[0087] P1=ρ0D m v1 (14)
[0088] Substituting (13) into the above formula (14) we get:
[0089]
[0090] 1. Deepwater conditions
[0091] The depth of the blasthole is h0 and the charge length is 1m, so the explosive is located at the water depth h0.
[0092] According to the research on cofferdam demolition blasting in deep water, the water pressure in deep water will reduce the detonation velocity of emulsion explosives. The test results of the reduction of detonation velocity of common industrial emulsion explosives under the action of water pressure in deep water are as follows: Figure 4 shown.
[0093] The relationship between water pressure P0 and water depth h0 is shown in formula (16):
[0094] P0=ρ0gh0 (16)
[0095] Where ρ0 is the density of water 1000 kg / m 3 , g is the acceleration due to gravity 10m / s 2 .
[0096] Depend on Figure 3 The relationship between the detonation velocity D of the emulsion explosive and the water depth h0 at a water depth of 30 m can be obtained from formula (16). When the water depth h0 = 30 m, the detonation velocity D of the emulsion explosive is 3000 m / s.
[0097] ρ2 is the density of the explosive, 1061 kg / m 3, the emulsion explosive blast velocity is 5000 m / s, the pressure on the detonation wave front in formula (10) γ is the adiabatic index of detonation products, taking 3, P L .
[0098]
[0099] After conversion, we have:
[0100]
[0101] ρ0 is the density of the undisturbed water medium 1000 kg / m 3 ; P0 is the pressure of the undisturbed water medium, ignoring hydrostatic pressure, taking 0.
[0102]
[0103] ρ1 is the initial shock wave density in water.
[0104]
[0105] In the P-v plane, the shock wave P-v curve in water can be drawn from formula (20); the rarefaction wave P-v curve in the explosion products can be drawn from formula (18), and the water shock wave graph is shown in Figure 5 .
[0106] From the intersection of the explosion product rarefaction curve and the water shock wave, the particle velocity v x and the shock wave front pressure P x on the shock wave front can be obtained, and then substituted into formula (13), (19) to obtain the water shock wave velocity D w , and the initial shock wave density in water ρ1.
[0107] 2. Shallow water case
[0108] The overall derivation process is similar to the deep water case. As shown in Figure 6 , since the explosive is buried in the water at a shallow position, the density of the explosive 1061 kg / m 3 can be directly taken, the emulsion explosive blast velocity D is 5000 m / s, and substituted into formula (10) to have:
[0109]
[0110] After conversion, we have:
[0111]
[0112] ρ0 is the density of the undisturbed water medium 1000 kg / m 3 ; P0 is the pressure of the undisturbed water medium, ignoring hydrostatic pressure, taking 0.
[0113]
[0114] ρ1 is the density of the initial shock wave in water.
[0115]
[0116] In the P-v plane, the shock wave P-v curve in water can be plotted from equation (20); the rarefaction wave P-v curve in the explosion products can be plotted from equation (18'), and the shock wave in water is plotted as shown in Figure 7
[0117] Then, the shock wave velocity D w in water and the density of the initial shock wave in water ρ1 can be obtained by substituting equations (13) and (19) into equations (13) and (19).
[0118] Step three, the peak value of the cylindrical shock wave in water at a certain point is calculated by using the attenuation law of the cylindrical shock wave in water. Further, the initial pressure of the shock wave in water acting on the borehole wall is obtained by using the acoustic approximation theory.
[0119] The cylindrical charge is in the borehole, and the shock wave generated in water is a cylindrical shock wave. The attenuation law of the cylindrical shock wave in water is:
[0120]
[0121] In the formula, ΔP(t) is the shock wave pressure attenuation amount within time t from the initiation, the unit of t is s; R is the distance from the axis of the cartridge, the unit is m; C0 is the shock wave velocity in water, the unit is m / s; σ0 is a function of time t, which is expressed by the following formula:
[0122]
[0123] is the peak value of the shock wave at a certain point, 105Pa, which is a function of distance R. For a TNT cartridge, there is:
[0124]
[0125] wherein, is the proportional distance, the unit is W c is the TNT equivalent per meter length of charge, the unit is kg / m; which is calculated according to the following formula:
[0126] W c = W cs Q Ws / Q WT (26)
[0127] In the above formula, W cs is the relative mass of a given explosive charge (per unit length), in kg; Q Ws is the heat of explosion (specific energy) of the explosive under consideration, in kcal / kg; Q WT ≈1000kcal / kg.
[0128] The diameter of the blasthole is 0.146m, the diameter of the explosive d is 0.06m, and ρ2 is the density of the explosive 1061kg / m 3 , the explosion heat Q of No. 2 rock emulsion explosive Ws The heat of explosion for a shallow-water coupled explosive charge is 881 kcal / kg (1 cal = 4.18 J). Since the explosive properties (such as detonation velocity, intensity, and work capacity) are directly proportional to the explosive heat, the heat of explosion at a depth of 30 m is 528.6 kcal / kg.
[0129] The relative mass per unit length 3kg; TNT equivalent of charge per meter length W c =W cs Q Ws / Q WT , is 2.64kg / m; proportional distance for Shock wave peak
[0130] The initial pressure of the underwater explosion shock wave acting on the blasthole wall is calculated by the following process:
[0131] When a shock wave in water acts vertically on a fixed rigid body, the particles moving on the wave front will suddenly stop moving, causing the overpressure to increase to the maximum, and the reflected wave will propagate in the opposite direction of the incident wave.
[0132] The initial pressure of the rock interface is determined according to the acoustic approximation theory:
[0133]
[0134] Where: Δp φT is the initial pressure at the rock interface, ρ0 is the undisturbed density of water, D w is 3005m / s, ρ0D w is the impact impedance of the explosive, ρ m v m The rock wave impedance is 135 MPa / s, which is the most common granite wave impedance. have to
[0135] Step 4: The shock wave continues to pass through the water-rock interface and then transmits into the rock, forming a transmission stress wave in the rock. Then it propagates along the radial direction of the blasthole. Due to the continuous compression of the rock medium, the wave velocity decreases and the stress peak attenuates. The peak stress σ at the distance r from the blasthole axis is calculated. r :
[0136]
[0137] Where: σ r are the radial stress in the rock, MPa; α is the stress wave attenuation index, α = 2-μ / (1-μ), μ is the Poisson's ratio of the rock, 0.25; λ is the lateral stress coefficient, its value is related to the Poisson's ratio of the rock and the stress wave propagation distance, and is larger in the near-blast zone, but as the distance increases, its value tends to depend only on the fixed value of the Poisson's ratio, λ = μ / (1-μ) = 0.25 / (1-0.25) = 0.33; r c is the radius of the blasthole, 0.073m, and the distance r from the blasthole axis is 0.3m.
[0138] Step 5: Based on the principle of reducing detonation velocity without changing density, the small-diameter high-detonation-velocity explosive package coupled charge is equivalently amplified to the large-diameter low-detonation-velocity explosive package coupled charge, and the stress value in the rock after the explosion is solved to reach σ r The detonation velocity D3 at this time is the detonation velocity of large diameter low detonation velocity explosive. Combine the following equations:
[0139] Pressure P3 on the detonation wave front of low detonation velocity large diameter explosive:
[0140]
[0141] Where: P3 is the average initial pressure of large diameter low detonation velocity explosive; ρ3 is the density of large diameter low detonation velocity explosive; D3 is the detonation velocity of large diameter low detonation velocity explosive; γ is the isentropic index of explosive, which is generally taken as 3 for industrial explosives.
[0142] Determine the initial pressure P of the rock interface based on the acoustic approximation theory m :
[0143]
[0144] Where: P m is the initial pressure of the rock interface, ρ3D3 is the impact impedance of the explosive, ρ m v m is the granite wave impedance. And:
[0145] σ r =P m (29)
[0146] The conclusion is: the detonation velocity of large diameter low detonation velocity explosive is D3.
[0147] Step six, the detonation velocity of large diameter low detonation velocity explosive obtained by the above calculation is taken as a condition to establish the explosive detonation state equation to simulate the detonation state of the coupled charge explosive. The explosive detonation state equation is described by the JWL equation:
[0148]
[0149] wherein P is the pressure, A, B, R1, R2 and ω are material constants related to the explosive respectively; V is the relative volume, E0 is the initial specific internal energy, V CJ is the explosion volume of the explosive, ρ is the density of the explosive, A = 5.35545ρv 2 , B = 0.094983ρv 2 , R1 = 4.2, R2 = 0.27R1, ω = 0.33,
[0150]
[0151] This embodiment takes the deep water radial water coupled charge as an example to model and illustrate the effect.
[0152] For small diameter high detonation velocity explosive, the ρ and v2 of formula (30) are substituted by the explosive density ρ1 and detonation velocity D:
[0153] A = 5.35545ρ1D 2 = 1.42×10 11 Pa; B = 0.094983ρ1D 2 = 2.52×10 9 Pa; R1 = 4.2;
[0154] R2 = 0.27R1 = 1.13; ω = 0.33; E0 = ρ1D 2 (0.204-0.0734ρ1) = 3.35×10 9 Pa;
[0155]
[0156] For large diameter low detonation velocity explosive, the ρ and v2 of formula (27) are substituted by the explosive density ρ3 and detonation velocity D3:
[0157] R1 = 4.2;
[0158] R2 = 0.27R1 = 1.13; ω = 0.33;
[0159]
[0160] The results of modeling by directly substituting the properties of small diameter high detonation velocity explosive charge into formula (29) are as followsFigure 8 As shown in the figure, the properties of the large diameter low detonation velocity explosive package are substituted into formula (29) to perform modeling. Figure 9 As shown in the figure, the model built directly from the small-diameter, high-detonation-velocity data contains distorted meshes (marked in red), which affects the calculation accuracy. However, the model built by scaling up the small-diameter, high-detonation-velocity explosive to a large-diameter, low-detonation-velocity explosive charge does not have distorted meshes.
[0161] The screenshots of the background data for modeling small-diameter high-detonation-velocity explosives and large-diameter low-detonation-velocity explosives are as follows: Figure 10 and Figure 11 As shown in the figure, it can be seen that for the numerical simulation of the same amount of explosives, the time consumed is reduced from 4 hours, 4 minutes and 59 seconds to 8 minutes and 45 seconds, saving nearly 30 times the computing time. If larger data is modeled for real experiments, the time saved will be considerable.
[0162] The screenshots of the memory usage of the modeling background data of small diameter high detonation velocity explosives and large diameter low detonation velocity explosives are as follows: Figure 12 and Figure 13 As shown in the figure, for numerical simulation of the same amount of explosives, the occupied units are reduced from 30540 to 27844, saving nearly 10% of memory. If larger data is modeled for real experiments, the memory savings will also be considerable.
[0163] The present invention provides a numerical simulation method for equivalently amplifying cylindrical explosives in radial water-coupled charging. By utilizing the rule that the total energy released when a small-diameter high-detonation-velocity explosive charge explodes in water is equal to the total energy released when a large-diameter low-detonation-velocity cylindrical charge explodes, a detonation state equation of the corresponding explosive is established after equivalent amplification. This method effectively describes the explosion state, achieves good modeling results, does not generate deformed meshes, and can significantly reduce calculation time and save storage memory.
[0164] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
[0165] The present invention is described with reference to flowcharts and / or block diagrams of methods, apparatus (modules, systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts 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, a special-purpose computer, an embedded computer, or other programmable data processing device to produce 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 flowcharts and / or block diagrams. 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.
[0166] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.
[0167] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.
[0168] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.
[0169] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.
Claims
1. A numerical simulation method for equivalently amplifying cylindrical explosives during radial water-coupled charging, characterized in that: The method comprises: Step 1: Select a small diameter high detonation velocity columnar explosive charge with water coupling, explosive density is ρ2, and detonation velocity is D; Step 2: Draw the Pv curve of the shock wave in water and the Pv curve of the rarefaction wave in the explosion product, and obtain the shock wave front particle velocity v at the explosive-water interface from the intersection of the two curves. x and the shock wave front pressure P x ; Step 3: Calculate the peak value of the cylindrical shock wave at a certain point in water using the attenuation law of the cylindrical shock wave in water Then, the initial pressure of the underwater shock wave acting on the blast hole wall is obtained by the acoustic approximation theory. Step 4: The shock wave continues to pass through the water-rock interface and then transmits into the rock, forming a transmission stress wave in the rock. Then it propagates along the radial direction of the blasthole and calculates the peak stress σ at the distance r from the blasthole axis. r ; Step 5: Based on the principle of reducing detonation velocity without changing density, the small-diameter high-detonation-velocity explosive package coupled charge is equivalently amplified to the large-diameter low-detonation-velocity explosive package coupled charge, and the stress value in the rock after the explosion is solved to reach σ r The detonation velocity D3 at that time is the detonation velocity of large diameter low detonation velocity explosive; Step 6: The detonation velocity of the large-diameter low-detonation-velocity explosive obtained by the above calculation is used as a condition to establish the explosive detonation state equation to simulate the detonation state of the coupled charge explosive.
2. The numerical simulation method for equivalently amplifying cylindrical explosives during radial water-coupled charging according to claim 1, characterized in that: When the water-coupled charge of the small-diameter high-detonation-velocity columnar explosive package described in step 1 adopts deep-water charge, step 2 draws the underwater shock wave Pv curve using the following formula: Where P1 is the pressure of the initial shock wave in water, ν w is the velocity of the shock wave front particle in water; the rarefaction wave Pv curve in the explosion product is drawn using the following formula: Among them, P x and v x are the velocities at the interface between detonation products and water, respectively.
3. The numerical simulation method for equivalently amplifying cylindrical explosives during radial water-coupled charging according to claim 1, characterized in that: When the water-coupled charge of the small-diameter high-detonation-velocity cylindrical explosive package described in step 1 adopts shallow water charge, step 2 draws the underwater shock wave Pv curve using the following formula: Where P1 is the pressure of the initial shock wave in water, ν w is the velocity of the shock wave front particle in water; the rarefaction wave Pv curve in the explosion product is drawn using the following formula: Among them, P x and v x are the velocities at the interface between detonation products and water, respectively.
4. The numerical simulation method for equivalently amplifying cylindrical explosives during radial water-coupled charging according to claim 1, characterized in that: The initial pressure of the underwater shock wave acting on the blast hole wall in step 3 Calculated by the following formula: Where ρ0 is the undisturbed density of water, D w is the shock wave front velocity in water, ρ0D w is the impact impedance of the explosive, ρ m v m is the rock wave impedance.
5. The numerical simulation method for equivalently amplifying cylindrical explosives during radial water-coupled charging according to claim 1, characterized in that: The peak stress σ at the distance r from the blasthole axis in step 4 r Calculated by the following formula: Among them, r c is the blasthole radius, α is the stress wave attenuation exponent, α = 2-μ / (1-μ), and μ is the Poisson's ratio of the rock.
6. The numerical simulation method for equivalently amplifying cylindrical explosives during radial water-coupled charging according to claim 1, characterized in that: The detonation velocity D3 of the large-diameter low-detonation-velocity explosive described in step 5 is obtained by combining the following formulas: s r =P m (29) Where P3 is the average initial pressure of large diameter low detonation velocity explosive, ρ3 is the density of large diameter low detonation velocity explosive, γ is the isentropic index of explosive, P m is the initial pressure at the rock interface, ρ3D3 is the impact impedance of small diameter high detonation velocity explosive, ρ m v m is the rock wave impedance.
7. The numerical simulation method for equivalently amplifying cylindrical explosives during radial water-coupled charging according to claim 1, characterized in that: The explosive detonation state equation described in step 6 adopts the JWL equation, which is described as: Where P is pressure, A, B, R1, R2 and ω are material constants related to explosives; V is relative volume, E0 is initial specific internal energy, V CJ is the explosive volume of the explosive, ρ is the density of the explosive, A=5.35545ρv 2 , B=0.094983ρv 2 , R1=4.2, R2=0.27R1, ω=0.33, 8. The numerical simulation method for equivalently amplifying cylindrical explosives during radial water-coupled charging according to claim 1, characterized in that: The explosive used is rock emulsion explosive.