Method for constructing shock wave overpressure calculation model under high-speed dynamic explosion condition of open-space ammunition

Abstract

The invention relates to the technical field of shock wave overpressure calculation modeling, in particular to a method for constructing a shock wave overpressure calculation model under the condition of high-speed kinetic explosion of open-space ammunition. The method comprises the following steps of: obtaining actual measurement data, removing impurity data, screening actual measurement effective data, performing constant fitting on the actual measurement effective data and three-order, high-order and segmented shock wave overpressure calculation empirical formulas, and calculating overpressure data of each measurement point by using the fitted three-order, high-order and segmented empirical formulas. And comparing the calculated overpressure data with actually measured data, calculating an error, calculating an average error, then selecting a formula with the minimum average error obtained by three empirical formulas as a corresponding ammunition shock wave overpressure calculation formula, and fully considering the influence of different ammunition use environments, falling speeds, falling angles and ammunition specifications and models. And a model support is provided for evaluating the shock wave damage capability of different ammunitions on target striking.

Description

Technical Field

[0001] The invention relates to the technical field of shock wave overpressure calculation modeling, in particular to a method for constructing a shock wave overpressure calculation model under high-speed dynamic explosion conditions of air-to-ground ammunition. Background Art

[0002] Shock waves are one of the main means of killing and damaging targets by conventional weapons. As the intensity of shock waves decays rapidly during propagation, its killing range is limited. Therefore, studying the overpressure of shock waves on targets to achieve maximum killing and damage to targets has become the focus of current research. It is also difficult to accurately determine the overpressure damage calculation of air-to-ground ammunition shock waves on targets under different models, specifications, falling speeds, falling angles and different environments.

[0003] The original explosion shock wave damage capability assessment model is usually based on the standard killing law formula ((ΔP-P * )×(II * )=K) to describe, where I * , I * , K is a constant (critical value at the air shock wave front), these three constants depend on the vulnerability of the target; I is the specific impulse value of the air shock wave, and the calculation formula is:

[0004] W θ is the equivalent TNT equivalent of the air-to-ground ammunition charge, and R is the distance from the point of impact of the shock wave to the point where the air-to-ground ammunition lands. Then, P1 is used to represent the probability of damage caused by the explosion, then:

[0005] Therefore, how to determine the overpressure value of the shock wave front based on different ammunition specifications, models, falling speeds, falling angles, environments, etc. becomes a difficult point in the calculation and evaluation of the damage of ammunition to the target.

[0006] Based on this, there is an urgent need to study the calculation formula for the shock wave overpressure of ammunition under different ammunition, different usage environments, different falling angles and different falling speeds, and to provide a method for constructing a shock wave overpressure calculation model under high-speed dynamic explosion conditions of air-to-ground ammunition. Summary of the invention

[0007] In order to solve the above technical problems existing in the prior art, the present invention provides a method for constructing a shock wave overpressure calculation model under high-speed dynamic explosion conditions of air-to-ground ammunition.

[0008] This is achieved specifically through the following technical solutions:

[0009] The method for constructing a shock wave overpressure calculation model under high-speed dynamic explosion conditions of air-to-ground ammunition includes:

[0010] Step 1: Constructing a shock wave overpressure measurement model

[0011] Establish an XZ coordinate system on the target of air-to-ground ammunition; draw a number of concentric circles with the origin of the XZ coordinate system as the center, and draw two mutually perpendicular straight lines through the centers; arrange pressure sensors at the intersections of the straight lines and the concentric circles to construct a shock wave overpressure measurement model under high-speed dynamic explosion conditions of air-to-ground ammunition;

[0012] Step 2: Analyze the measured data and eliminate abnormal measured values ​​to select the measured data of valid measuring points;

[0013] Step 3: Randomly use the measured data of effective measuring points, use the shock wave overpressure empirical formula to fit the constant, compare and analyze the errors of various forms of shock wave overpressure empirical formulas obtained after fitting and the measured data of each measuring point, calculate the average error, and select the shock wave overpressure formula with the smallest error, that is, form the shock wave overpressure calculation formula; the shock wave empirical formula is:

[0014] (1) Third-order empirical formula:

[0015]

[0016] (2) High-level empirical formula:

[0017]

[0018] (3) Segmented empirical formula:

[0019]

[0020] Where R is the distance from the impact point of the shock wave to the landing point of the air-to-ground ammunition, W θ is the equivalent TNT of the air-to-ground ammunition charge; the W θ The calculation method is:

[0021] W θ =W 战斗部 ×f c

[0022] Where: W 战斗部 is the charge mass of air-to-ground ammunition, f c is the charge equivalent conversion factor.

[0023] Preferably, the second step is: first calculate and find the mathematical expectation value E(P) of the measured data measured at each measuring point; compare the measured data measured at the i-th measuring point with the mathematical expectation value E(P), and satisfy: |P i -E(P)|≥3σ, σ is the mean square error of the valid data of each measuring point, then the measured data measured at the ith measuring point are abnormal data and should be eliminated; otherwise, they are the measured data of the valid measuring point and are retained.

[0024] Compared with the prior art, the technical effects created by the present invention are embodied in:

[0025] The invention creates a method of fitting constants using measured data, removing impurity data and screening measured effective data, using the measured effective data and third-order, high-order and segmented empirical formulas for calculating shock wave overpressure, and then using the fitted third-order, high-order and segmented empirical formulas to calculate the overpressure data of each measuring point, comparing the calculated overpressure data with the measured data and calculating the error, finding the average error, and then selecting the formula with the smallest average error obtained from the three empirical formulas as the corresponding ammunition shock wave overpressure calculation formula, fully considering the influence of different ammunition use environments, falling speeds, falling angles, and ammunition specifications and models, and providing a model support for evaluating the shock wave damage capabilities of different ammunition on targets.

[0026] The invention creates an example in which air-to-ground ammunition is selected as the ammunition for research to achieve the strike on the target, and then forms a scientific model suitable for calculating the overpressure value of the shock wave of the air-to-ground ammunition explosion, which can realize the evaluation of whether the target is damaged by the shock wave overpressure impact as a result of the air-to-ground ammunition striking the target. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 Creating a target detection schematic diagram for the present invention DETAILED DESCRIPTION

[0027] The technical solution of the present invention is further defined below in conjunction with the accompanying drawings and specific implementation methods, but the scope of protection required is not limited to the description.

[0028] The method for constructing a shock wave overpressure calculation model under high-speed dynamic explosion conditions of air-to-ground ammunition includes:

[0029] Step 1: Constructing a shock wave overpressure measurement model

[0030] Establish an XZ coordinate system on the target of air-to-ground ammunition; draw a number of concentric circles with the origin of the XZ coordinate system as the center, and draw two mutually perpendicular straight lines through the centers; arrange pressure sensors at the intersections of the straight lines and the concentric circles to construct a shock wave overpressure measurement model under high-speed dynamic explosion conditions of air-to-ground ammunition;

[0031] Step 2: Analyze the measured data and eliminate abnormal measured values ​​to select the measured data of valid measuring points;

[0032] Step 3: Randomly use the measured data of effective measuring points, use the shock wave overpressure empirical formula to fit the constant, compare and analyze the errors of various forms of shock wave overpressure empirical formulas obtained after fitting and the measured data of each measuring point, calculate the average error, and select the shock wave overpressure formula with the smallest error, that is, form the shock wave overpressure calculation formula; the shock wave empirical formula is:

[0033] (1) Third-order empirical formula:

[0034]

[0035] (2) High-order empirical formula:

[0036]

[0037] (3) Segmented empirical formula:

[0038]

[0039] Where R is the distance from the impact point of the shock wave to the landing point of the air-to-ground ammunition, W θ is the equivalent TNT of the air-to-ground ammunition charge; the W θ The calculation method is:

[0040] W θ =W 战斗部 ×f c

[0041] Where: W 战斗部 is the charge mass of air-to-ground ammunition, f c is the charge equivalent conversion factor.

[0042] In some embodiments, the second step is: first calculate and find the mathematical expectation value E(P) of the measured data measured at each measuring point; compare the measured data measured at the i-th measuring point with the mathematical expectation value E(P), and satisfy: |P i -E(P)|≥3σ, σ is the mean square error of the valid data of each measuring point, then the measured data measured at the ith measuring point are abnormal data and should be eliminated; otherwise, they are the measured data of the valid measuring point and are retained.

[0043] Example: Figure 1 As shown in the figure, the measured shock wave overpressure sensor is arranged as follows Figure 1-1 6 points, and let the coordinates be (a, b); Figure 1 The coordinates of each point are shown in Table 1 below:

[0044] Table 1 Specific coordinates of target test shock wave overpressure sensor layout

[0045]

[0046] Air-to-ground ammunition is selected as the ammunition part for model construction and actual data measurement. The location of the ammunition drop point is as follows Figure 1As shown, according to the data measured by the deployed sensors, the above method is used for fitting calculation, and the error of using the third-order empirical formula to calculate the impact of this type of ammunition on the target is: the third order is the smallest. Therefore, the third-order empirical formula is selected as the calculation formula for the shock wave overpressure of air-to-ground ammunition, and combined with the three constant values ​​of a, b, and c obtained by fitting, and after correction, it is obtained:

[0047]

[0048] Other matters not covered by the invention may be implemented by referring to the prior art or common knowledge and conventional technical means known to those skilled in the art, for example, how to use the measured data determined by screening to respectively fit the constants in the third-order, high-order, and segmented empirical formulas, which can be calculated by using the substitution method and randomly taking measured point data.

[0049] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for constructing a shock wave overpressure calculation model under high-speed dynamic explosion conditions of air-to-ground ammunition, characterized in that: include: Step 1: Constructing a shock wave overpressure measurement model Establish an XZ coordinate system on the target of air-to-ground ammunition; draw a number of concentric circles with the origin of the XZ coordinate system as the center, and draw two mutually perpendicular straight lines through the centers; arrange pressure sensors at the intersections of the straight lines and the concentric circles to construct a shock wave overpressure measurement model under high-speed dynamic explosion conditions of air-to-ground ammunition; Step 2: Analyze the measured data and eliminate abnormal measured values ​​to select the measured data of valid measuring points; Step 3: Randomly use the measured data of effective measuring points, use the shock wave overpressure empirical formula to fit the constant, compare and analyze the errors of various forms of shock wave overpressure empirical formulas obtained after fitting and the measured data of each measuring point, calculate the average error, and select the shock wave overpressure formula with the smallest error, that is, form the shock wave overpressure calculation formula; the shock wave empirical formula is: (1) Third-order empirical formula: (2) High-level empirical formula: (3) Segmented empirical formula: Where R is the distance from the impact point of the shock wave to the landing point of the air-to-ground ammunition, W θ is the equivalent TNT of the air-to-ground ammunition charge; the W θ The calculation method is: IN θ =In 战斗部 ×f c Where: W 战斗部 is the charge mass of air-to-ground ammunition, f c is the charge equivalent conversion factor.

2. The method for constructing a shock wave overpressure calculation model under high-speed dynamic explosion conditions of air-to-ground ammunition as claimed in claim 1, characterized in that: The second step is: first calculate and find the mathematical expectation value E(P) of the measured data of each measuring point; compare the measured data of the i-th measuring point with the mathematical expectation value E(P), and satisfy: |P i -E(P)|≥3σ, σ is the mean square error of the valid data of each measuring point, then the measured data measured at the ith measuring point are abnormal data and should be eliminated; otherwise, they are the measured data of the valid measuring point and are retained.

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