A method for quickly calculating pressure load of adjacent cabin of implosion main cabin breakage

Abstract

This invention relates to a rapid calculation method for pressure load in adjacent compartments damaged by an internal explosion in the main compartment, belonging to the field of explosion and damage technology. By establishing the relationship between detonation gas parameters in the main and adjacent compartments, a suitable algorithm is selected and programmed to quickly solve for the time history curves of gas pressure in the adjacent compartment. Compared with experimental or numerical simulation methods, this method saves significant manpower, material resources, and financial resources. Furthermore, by changing the initial input parameters, the pressure changes in the adjacent compartment under different operating conditions can be quickly calculated, saving time and providing rapid support for pre-battle prediction in actual combat or training exercises for the military.

Description

Technical Field

[0001] This invention belongs to the field of explosion and damage technology, and relates to a rapid calculation method for pressure load of adjacent compartments damaged by internal explosion in the main compartment. Background Technology

[0002] Anti-ship warheads primarily attack surface ships through armor-piercing implosion. High-speed fragmentation groups penetrate the surface with kinetic energy, causing the explosion and breaching of the compartment walls. The shockwave, after multiple reflections, convergences, and homogenizations along the breached main compartment walls, propagates to adjacent compartments, causing damage to a wider area of ​​the compartment structure and even overall ship destruction. The study, "Equivalent Scale Experimental Method and Damage Characteristics Research of Explosions Inside Box-Shaped Structures," obtained pressure load data for adjacent compartments in multi-compartment explosions through experiments, but did not provide a calculation method for the pressure load in adjacent compartments. Load is the main energy source causing structural damage. Obtaining pressure load data for adjacent compartments through experiments is not only resource-intensive but also slow, making it impossible to predict the extent of target damage in actual combat or training scenarios before engagement.

[0003] In summary, current methods for obtaining pressure loads in adjacent compartments damaged by internal explosions mainly rely on experiments or numerical simulations. These methods are time-consuming and labor-intensive, and cannot provide rapid pre-battle predictions or a clear understanding of the situation. Furthermore, they cannot support decision-making regarding the ammunition requirements for large-scale damage to actual combat targets. Therefore, there is an urgent need to establish a rapid calculation method for pressure loads in adjacent compartments damaged by internal explosions. Summary of the Invention

[0004] In view of the defects or deficiencies of existing methods for obtaining pressure loads of adjacent compartments damaged by internal explosions, the purpose of this invention is to provide a rapid calculation method for pressure loads of adjacent compartments damaged by internal explosions. This method solves the problem of time-consuming and labor-intensive methods for calculating the pressure loads of adjacent compartments damaged by internal explosions through experiments or numerical simulations, which cannot achieve rapid pre-explosion assessment of the current situation, and enables rapid calculation of pressure loads of adjacent compartments.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A rapid calculation method for pressure load in adjacent compartments damaged by an internal explosion in the main compartment, characterized by the following steps:

[0007] Step one: The propagation process of detonation gas from the main compartment to the adjacent compartment is divided into two stages;

[0008] In the first stage of the detonation gas flowing from the main compartment to the damaged area, let the initial pressure, initial density, and initial velocity of the detonation gas inside the main compartment be p0, ρ0, and u0, respectively; and the real-time pressure, density, and velocity of the detonation gas at the damaged area be p(t), ρ(t), and u(t), respectively; and let the state parameters between the detonation gases satisfy the following relationships in formulas (1) and (2):

[0009]

[0010]

[0011] In the formula, r is the gas polyhedral index; dp represents the differential of pressure.

[0012] In the second stage, as the detonation gas flows from the damaged area to the adjacent compartment, let the real-time pressure, density, and velocity of the gas inside the adjacent compartment be P2(t), ρ2(t), and u2(t), respectively; the state parameters between the detonation gases satisfy the following relationships in formulas (3) and (4):

[0013]

[0014]

[0015] Step two, since the initial velocity of the fluid u0 = 0, for the first stage of the above steps, substituting equation (1) into equation (2), the flow velocity of the detonation gas at the breach is expressed by equation (5):

[0016]

[0017] Since the kinetic energy of the detonation gas flowing into the adjacent compartment is converted into internal energy, u2(t) = 0. For the second stage in step one, substituting equation (3) into equation (4) yields another expression (6) for the detonation gas velocity at the breach:

[0018]

[0019] By combining equations (5) and (6), the real-time pressure of the detonation gas at the breach is obtained, which is expressed by equation (7):

[0020]

[0021] By combining equation (1), the real-time flow velocity of the detonation gas at the breach is obtained, which is expressed by equation (8):

[0022]

[0023] Step 3: Let the real-time masses of the detonation gases inside the main compartment and the adjacent compartment be M0(t) and M2(t), respectively. Within a time step Δt = t2 - t1, the expressions for the masses of the detonation gases in the main compartment and the adjacent compartment are given by equations (9) and (10), respectively:

[0024] M0(t2)=M0(t1)-dM0(t1)=M0(t1)-ρ(t)u(t)S*Δt (9);

[0025] M2(t2)=M2(t1)+dM0(t1)=M2(t1)+ρ(t)u(t)S*Δt (10);

[0026] In the formula, S is the area of ​​the breach;

[0027] Step 4: Let the real-time energies of the detonation gases inside the main compartment and the adjacent compartment be e0(t) and e2(t), respectively. Within a time step Δt = t2 - t1, the expressions for the detonation gas energies in the main compartment and the adjacent compartment are given by equations (11) and (12), respectively:

[0028]

[0029]

[0030] Step 5: Let the real-time pressures of the detonation gas inside the main compartment and the adjacent compartment be p0(t) and p2(t), respectively. Within a time step Δt = t2 - t1, the expressions for the detonation gas pressures in the main compartment and the adjacent compartment are given by equations (13) and (14), respectively:

[0031] p0(t2)=(r-1)ρ0(t2)e0(t2) (13);

[0032] p2(t2)=(r-1)ρ2(t2)e2(t2) (14);

[0033] Step 6: Combine equations (1), (7) to (14) and calculate the time history curve of the gas pressure in the adjacent compartment by programming and performing single-step iterative calculation.

[0034] Advantages of this invention:

[0035] By establishing the relationship between the detonation gas parameters in the main and adjacent compartments, and selecting an appropriate algorithm for programming, the gas pressure in the adjacent compartment can be quickly obtained. Compared with experimental or numerical simulation methods, this saves a significant amount of manpower, material resources, and financial resources. Furthermore, by changing the initial input parameters, the pressure changes in the adjacent compartment under different operating conditions can be calculated, saving time and providing rapid support for pre-battle prediction in actual combat or training exercises for the military. Attached Figure Description

[0036] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0037] Figure 1 This is a schematic diagram illustrating the two stages of pressure propagation in adjacent compartments after an internal explosion in this invention.

[0038] Figure 2The time history curves of gas pressure in the main and adjacent compartments are obtained by single-step iterative calculation. Detailed Implementation

[0039] The present invention will now be described in further detail with reference to the accompanying drawings and preferred embodiments.

[0040] The present invention provides a method for rapid calculation of pressure load in adjacent compartments damaged by an internal explosion in the main compartment. In specific implementation, the following steps are followed:

[0041] Step 1, follow the instructions. Figure 1 The diagram illustrates that the propagation of detonation gases from the main compartment to the adjacent compartment is divided into two stages;

[0042] In the first stage of the detonation gas flowing from the main compartment to the damaged area, let the initial pressure, initial density, and initial velocity of the detonation gas inside the main compartment be p0, ρ0, and u0, respectively; and the real-time pressure, density, and velocity of the detonation gas at the damaged area be p(t), ρ(t), and u(t), respectively; and let the state parameters between the detonation gases satisfy the following relationships in formulas (1) and (2):

[0043]

[0044]

[0045] In the formula, r is the gas polyhedral index; dp represents the differential of pressure.

[0046] In the second stage, as the detonation gas flows from the damaged area to the adjacent compartment, let the real-time pressure, density, and velocity of the gas inside the adjacent compartment be P2(t), ρ2(t), and u2(t), respectively; the state parameters between the detonation gases satisfy the following relationships in formulas (3) and (4):

[0047]

[0048]

[0049] Step two, since the initial velocity of the fluid u0 = 0, for the first stage of the above steps, substituting equation (1) into equation (2), the flow velocity of the detonation gas at the breach is expressed by equation (5):

[0050]

[0051] Since the kinetic energy of the detonation gas flowing into the adjacent compartment is converted into internal energy, u2(t) = 0. For the second stage in step one, substituting equation (3) into equation (4) yields another expression (6) for the detonation gas velocity at the breach:

[0052]

[0053] By combining equations (5) and (6), the real-time pressure of the detonation gas at the breach is obtained, which is expressed by equation (7):

[0054]

[0055] By combining equation (1), the real-time flow velocity of the detonation gas at the breach is obtained, which is expressed by equation (8):

[0056]

[0057] Step 3: Let the real-time masses of the detonation gases inside the main compartment and the adjacent compartment be M0(t) and M2(t), respectively. Within a time step Δt = t2 - t1, the expressions for the masses of the detonation gases in the main compartment and the adjacent compartment are given by equations (9) and (10), respectively:

[0058] M0(t2)=M0(t1)-dM0(t1)=M0(t1)-ρ(t)u(t)S*Δt (9);

[0059] M2(t2)=M2(t1)+dM0(t1)=M2(t1)+ρ(t)u(t)S*Δt (10);

[0060] In the formula, S is the area of ​​the breach;

[0061] Step 4: Let the real-time energies of the detonation gases inside the main compartment and the adjacent compartment be e0(t) and e2(t), respectively. Within a time step Δt = t2 - t1, the expressions for the detonation gas energies in the main compartment and the adjacent compartment are given by equations (11) and (12), respectively:

[0062]

[0063]

[0064] Step 5: Let the real-time pressures of the detonation gas inside the main compartment and the adjacent compartment be p0(t) and p2(t), respectively. Within a time step Δt = t2 - t1, the expressions for the detonation gas pressures in the main compartment and the adjacent compartment are given by equations (13) and (14), respectively:

[0065] p0(t2)=(r-1)ρ0(t2)e0(t2) (13);

[0066] p2(t2)=(r-1)ρ2(t2)e2(t2) (14);

[0067] Step 6: Combine equations (1), (7) to (14) and calculate the time history curve of the gas pressure in the adjacent compartment by programming and performing single-step iterative calculation.

[0068] The following are specific embodiments provided by the inventor.

[0069] Example 1: A rapid calculation method for pressure load in adjacent compartments after damage to the main compartment in an internal explosion. This method is applicable to explosions in multiple compartments and allows for rapid calculation of quasi-static pressure load in surrounding adjacent compartments after damage to a compartment during an explosion.

[0070] Step one, the propagation process of detonation gas from the main compartment to the adjacent compartment is divided into two stages, such as... Figure 1 As shown.

[0071] Phase 1: Detonation gas flows from the main compartment to the damaged area. Assume the initial pressure, initial density, and initial velocity of the detonation gas inside the main compartment are p0 = 0.99 MPa, ρ0 = 1.734 kg / dm³, and so on. 3 u0 = 0 m / s; the real-time pressure, density, and velocity of the detonation gas at the damaged site are p(t), ρ(t), and u(t), respectively. The state parameters between the detonation gases in this stage satisfy the following relationships according to formulas (1) and (2):

[0072]

[0073]

[0074] In the formula, r = 1.4 is the gas polyhedral index, and dp represents the differential of pressure;

[0075] Second stage: Detonation gases flow from the damaged area into the adjacent compartment. Let the real-time pressure, density, and velocity of the gas inside the adjacent compartment be P2(t), ρ2(t), and u2(t), respectively. The state parameters between the detonation gases in this stage satisfy the following relationships from equations (3) and (4):

[0076]

[0077]

[0078] Step two, for the first stage in step one, since the initial velocity of the fluid is u0 = 0, substituting equation (1) into equation (2), the velocity of the detonation gas at the breach is obtained and expressed by equation (5):

[0079]

[0080] For the second stage in step one, since the kinetic energy of the detonation gas flowing into the adjacent compartment is converted into internal energy, the velocity u2(t) = 0. Substituting equation (3) into equation (4), another expression (6) for the flow velocity of the detonation gas at the breach is obtained:

[0081]

[0082] By combining equations (5) and (6), the real-time pressure of the detonation gas at the breach is obtained, which is expressed by equation (7):

[0083]

[0084] By combining equation (1), the real-time flow velocity of the detonation gas at the breach is obtained, which is expressed by equation (8):

[0085]

[0086] Step 3, let the real-time masses of the detonation gas inside the main compartment and the adjacent compartment be M0(t) and M2(t), respectively. Within a time step Δt = t2 - t1 = 0.000001s, the expressions for the masses of the detonation gas inside the main compartment and the adjacent compartment are given by equations (9) and (10), respectively:

[0087] M0(t2)=M0(t1)-dM0(t1)=M0(t1)-ρ(t)u(t)S*Δt (9);

[0088] M2(t2)=N2(t1)+dM0(t1)=M2(t1)+ρ(t)u(t)S*Δt (10);

[0089] In the formula, S = 0.0572m 2 This represents the area of ​​the breach.

[0090] Step 4: Let the real-time energies of the detonation gases inside the main compartment and the adjacent compartment be e0(t) and e2(t), respectively. Within a time step Δt = t2 - t1 = 0.000001s, the expressions for the detonation gas energies inside the main compartment and the adjacent compartment are given by equations (11) and (12), respectively:

[0091]

[0092]

[0093] Step 5: Let the real-time pressures of the detonation gas inside the main compartment and the adjacent compartment be p0(t) and p2(t), respectively. Within a time step Δt = t2 - t1 = 0.000001, the expressions for the detonation gas pressures in the main compartment and the adjacent compartment are given by equations (13) and (14), respectively:

[0094] p0(t2)=(r-1)ρ0(t2)e0(t2) (13);

[0095] p2(t2)=(r-1)ρ2(t2)e2(t2) (14);

[0096] Step 6: Combine equations (1) and (7) to (14), and use programming to perform single-step iterative calculations to obtain the time history curves of the gas pressure in the main and adjacent compartments, as shown below. Figure 2 As shown in the figure. The peak pressure in the adjacent compartment was 0.47 MPa, and the peak arrival time was 5.87 ms.

[0097] The present invention is not limited to the above embodiments, and its technical solutions have been described in the invention content section.

[0098] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0099] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0100] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A method for rapid calculation of pressure load in adjacent compartments damaged by an internal explosion in the main compartment, characterized in that, The method includes the following steps: Step one: The propagation process of detonation gas from the main compartment to the adjacent compartment is divided into two stages; In the first stage of the detonation gas flowing from the main compartment to the damaged area, let the initial pressure, initial density, and initial velocity of the detonation gas inside the main compartment be p0, ρ0, and u0, respectively; and the real-time pressure, density, and velocity of the detonation gas at the damaged area be p(t), ρ(t), and u(t), respectively; and let the state parameters between the detonation gases satisfy the following relationships in formulas (1) and (2): In the formula, r is the gas polyhedral index; dp represents the differential of pressure. In the second stage, as the detonation gas flows from the damaged area to the adjacent compartment, let the real-time pressure, density, and velocity of the gas inside the adjacent compartment be P2(t), ρ2(t), and u2(t), respectively; the state parameters between the detonation gases satisfy the following relationships in formulas (3) and (4): Step two, since the initial velocity of the fluid u0 = 0, for the first stage of the above steps, substituting equation (1) into equation (2), the flow velocity of the detonation gas at the breach is expressed by equation (5): Since the kinetic energy of the detonation gas flowing into the adjacent compartment is converted into internal energy, u2(t) = 0. For the second stage in step one, substituting equation (3) into equation (4) yields another expression (6) for the detonation gas velocity at the breach: By combining equations (5) and (6), the real-time pressure of the detonation gas at the breach is obtained, which is expressed by equation (7): By combining equation (1), the real-time flow velocity of the detonation gas at the breach is obtained, which is expressed by equation (8): Step 3: Let the real-time masses of the detonation gases inside the main compartment and the adjacent compartment be M0(t) and M2(t), respectively. Within a time step Δt = t2 - t1, the expressions for the masses of the detonation gases in the main compartment and the adjacent compartment are given by equations (9) and (10), respectively: M0(t2)=M0(t1)-dM0(t1)=M0(t1)-ρ(t)u(t)S*Δt (9); M2(t2)=M2(t1)+dM0(t1)=M2(t1)+ρ(t)u(t)S*Δt (10); In the formula, S is the area of ​​the breach; Step 4: Let the real-time energies of the detonation gases inside the main compartment and the adjacent compartment be e0(t) and e2(t), respectively. Within a time step Δt = t2 - t1, the expressions for the detonation gas energies in the main compartment and the adjacent compartment are given by equations (11) and (12), respectively: Step 5: Let the real-time pressures of the detonation gas inside the main compartment and the adjacent compartment be p0(t) and p2(t), respectively. Within a time step Δt = t2 - t1, the expressions for the detonation gas pressures in the main compartment and the adjacent compartment are given by equations (13) and (14), respectively: p0(t2)=(r-1)ρ0(t2)e0(t2) (13); p2(t2)=(r-1)ρ2(t2)e2(t2) (14); Step 6: Combine equations (1), (7) to (14) and calculate the time history curve of the gas pressure in the adjacent compartment by programming and performing single-step iterative calculation.

Images