Method for calculating arrival time of explosive shock waves under high-pressure gas condition

Abstract

The invention relates to the technical field of explosion shock wave arrival time prediction, and discloses an explosion shock wave arrival time calculation method under a high-pressure gas condition, and the method comprises the steps: obtaining the sectional area of a measurement point, the initial atmospheric pressure, the final inflation relative pressure value before explosion of an explosive, and the space volume between a detonation point and a pressure measurement point; based on the initial atmospheric pressure and the final inflation relative pressure value before explosive explosion, the final inflation absolute pressure value before explosive explosion and the corresponding air density are determined; determining a shock wave arrival time correlation coefficient; and calculating the shock wave arrival time under the high-pressure condition based on the sectional area, the space volume, the final inflation absolute pressure value before explosive explosion and the corresponding air density and shock wave arrival time correlation coefficient of the measurement point. The shock wave arrival time can be accurately calculated, and technical support is provided for determination of high-pressure gas release time, effective coupling of high-pressure gas and explosion energy, calculation of shock wave velocity in air with different densities and the like.

Description

Technical Field

[0001] The invention relates to the technical field of explosion shock wave arrival time prediction, in particular to a method for calculating the explosion shock wave arrival time under high-pressure gas conditions. Background Art

[0002] Under the conditions of joint driving of high-pressure gas and explosive explosion, high-peak and long-duration dynamic loads can be generated in the explosion wave simulation device, which can simulate various forms of shock wave loads, dynamic loads of the external flow field during the flight of the aircraft, and dynamic loads of the internal flow field during the separation of the mechanism. Under the joint driving conditions, the effective coupling of high-pressure gas and explosion energy is the main technical means to control the dynamic load. Therefore, the arrival time of the explosion shock wave is the key parameter to control the energy release of high-pressure gas and the dynamic load form.

[0003] At present, researchers at home and abroad have done a lot of basic work on the study of explosion shock waves under free atmosphere conditions and formed relatively mature calculation methods. However, most of the research on shock waves under different air pressure conditions focuses on theory, and there is little research on engineering calculation methods for shock wave parameters under high-pressure gas conditions. Moreover, most of the research focuses on the shock wave overpressure peak and positive pressure action time. Under such working conditions, the arrival time of the shock wave is not only related to factors such as the charge form, charge amount, and surface form of the explosion wave simulation device, but also closely related to the gas pressure. Therefore, research on the arrival time of the shock wave under high-pressure gas conditions is even more lacking.

[0004] As mentioned above, the arrival time of the shock wave is crucial to the determination of the release time of high-pressure energy and the coupling of explosion energy and high-pressure gas energy, which directly affects the simulation of dynamic loads of different forms. Therefore, accurate prediction of the arrival time of the shock wave is of great significance for the smooth simulation test of the explosion wave simulation device. However, the existing technology lacks effective engineering calculation methods for the arrival time of the explosion shock wave under high-pressure gas conditions, and in-depth research is urgently needed by those skilled in the art. Summary of the invention

[0005] The purpose of the present invention is to provide a method for calculating the arrival time of explosion shock waves under high-pressure gas conditions. The method is simple and efficient, can accurately calculate the arrival time of shock waves, and can provide effective technical support for determining the release time of high-pressure gas, effectively coupling high-pressure gas with explosion energy, calculating the shock wave velocity in air of different densities, and designing application experiments.

[0006] To achieve the above object, the present invention provides the following solutions: A method for calculating the arrival time of explosion shock waves under high pressure gas conditions, the method comprising the following steps: S1, obtain the cross-sectional area at the measuring point, the initial atmospheric pressure, and the final relative pressure of the explosive before explosion. 、The volume of space between the detonation point and the pressure measurement point; S2, determining the final inflation absolute pressure value before the explosion of the explosive and its corresponding air density based on the initial atmospheric pressure and the final inflation relative pressure value before the explosion of the explosive; S3, determine the shock wave arrival time correlation coefficient; S4, calculating the shock wave arrival time under high pressure conditions based on the cross-sectional area at the measuring point, the spatial volume, the final inflation absolute pressure value before the explosive explodes and its corresponding air density, the shock wave arrival time correlation coefficient and the charge amount.

[0007] Furthermore, the S1, obtaining the cross-sectional area at the measuring point, the initial atmospheric pressure, the final inflation relative pressure value before the explosion of the explosive, and the spatial volume between the detonation point and the pressure measuring point, specifically includes: Measure the cross-sectional area at the measuring point S j , initial atmospheric pressure P 0 ; Calculate the volume of the space between the detonation point and the pressure measurement point V t ; Measure the final relative pressure of the explosive before explosion P X。

[0008] Further, the step S2, based on the initial atmospheric pressure and the final relative pressure value of the explosive before the explosion, determines the final absolute pressure value of the explosive before the explosion and its corresponding air density, specifically including: Based on initial atmospheric pressure P 0 , Final inflation relative pressure value before explosive explosion P X , determine the final inflation absolute pressure value before the explosive explodes P c , the expression is as follows: P c = P 0 +P X (1) According to the corresponding relationship between atmospheric pressure and air density, the final inflation absolute pressure value is obtained. P c The corresponding air density ρ c。

[0009] Furthermore, the final inflation absolute pressure value is obtained according to the corresponding relationship between atmospheric pressure and air density. Pc The corresponding air density ρ c , specifically including: A table is established based on the corresponding relationship between atmospheric pressure and air density, and the final inflation absolute pressure value is obtained by table lookup method. P c The corresponding air density ρ c。

[0010] Further, the step S3, determining the shock wave arrival time correlation coefficient, specifically includes: Based on the cross-sectional form of the explosion wave simulation device, the distance from the detonation point of the explosive to the measurement point, and the final inflation absolute pressure value P c , the shock wave arrival time correlation coefficient is obtained by experiment or numerical calculation a tcy 、b tcy 、c tcy ,in, a tcy , b tcy is a coefficient related to the ratio of the distance from the measuring point to the detonation point and the equivalent diameter of the cross section at the measuring point; c tcy is the cross-sectional area at the detonation point S c and the cross-sectional area at the measuring point S j The coefficient related to the ratio.

[0011] Further, the step S4 calculates the shock wave arrival time under high pressure conditions based on the cross-sectional area at the measuring point, the spatial volume, the final inflation absolute pressure value of the explosive before explosion and its corresponding air density, the shock wave arrival time correlation coefficient and the charge amount, specifically including: The calculation formula for the shock wave arrival time under high pressure conditions is as follows: (2) in, t c is the shock wave arrival time, Q For the charge amount.

[0012] Furthermore, in S4, the time before the shock wave arrives under high pressure is calculated using formula (2), according to the charge amount Q、 Cross-sectional area at the measuring point S j , the volume of space between the detonation point and the pressure measurement point V t , Final inflation absolute pressure value before explosive explosionP c , respectively calculated S j / Q , Q / P c V t and P c V t / Q ; The calculated S j / Q , Q / P c V t and P c V t / Q Substituting into formula (2), we can obtain the shock wave arrival time under high pressure conditions: t c。

[0013] According to the specific embodiment provided by the present invention, the method for calculating the arrival time of explosion shock wave under high pressure gas conditions provided by the present invention discloses the following technical effects: Comprehensively consider multiple factors that affect the arrival time of the explosion shock wave, such as the cross-sectional area at the measurement point, the volume of the space, the final inflation absolute pressure value of the explosive before the explosion and its corresponding air density, the shock wave arrival time correlation coefficient, etc., to accurately calculate the explosion shock wave arrival time; Among them, based on the initial atmospheric pressure and the final relative inflation pressure value before the explosion of the explosive, the final absolute inflation pressure value before the explosion of the explosive and its corresponding air density are accurately determined, and combined with the cross-sectional form of the explosion wave simulation device, the distance from the detonation point of the explosive to the measuring point, and the shock wave arrival time-related parameters that are closely related to the absolute inflation pressure value, the research on the shock wave arrival time for different air densities under high-pressure gas conditions is realized, the calculation scheme is optimized, the calculation steps are simplified, and the explosion shock wave arrival time is obtained quickly and accurately, which can provide technical support for the timing control of high-pressure gas release, the calculation of shock wave velocities in air of different densities, and the design of application experiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0015] Figure 1 A flow chart of a method for calculating the arrival time of explosion shock waves under high-pressure gas conditions provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] The purpose of the present invention is to provide a method for calculating the arrival time of an explosion shock wave under high-pressure gas conditions. Aiming at the problem that the prior art lacks research on the arrival time of shock waves under high-pressure gas conditions, an efficient and simple calculation scheme is proposed to achieve accurate calculation of the arrival time of an explosion shock wave under high-pressure gas conditions, thereby providing technical support for determining the release time of high-pressure gas, effectively coupling high-pressure gas with explosion energy, calculating the shock wave velocity in air of different densities, and designing application experiments.

[0018] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] The method for calculating the arrival time of explosion shock waves under high-pressure gas conditions provided by the present invention comprises the following steps: S1, obtain the cross-sectional area at the measuring point, the initial atmospheric pressure, the final relative pressure value of the explosive before explosion, and the spatial volume between the detonation point and the pressure measurement point; S2, determining the final inflation absolute pressure value before the explosion of the explosive and its corresponding air density based on the initial atmospheric pressure and the final inflation relative pressure value before the explosion of the explosive; S3, determine the shock wave arrival time correlation coefficient; S4, calculating the shock wave arrival time under high pressure conditions based on the cross-sectional area at the measuring point, the spatial volume, the final inflation absolute pressure value before the explosive explodes and its corresponding air density, the shock wave arrival time correlation coefficient and the charge amount.

[0020] like Figure 1 As shown, the embodiment of the present invention takes a certain explosion wave simulation device as an example, the charge amount is 0.8KgTNT, and the method for calculating the arrival time of the explosion shock wave under the high pressure gas condition of the explosion wave simulation device specifically includes the following steps: Step 1: Measure the cross-sectional area at the measuring point S j , initial atmospheric pressure P0 This example is carried out in a certain explosion wave simulation device, and the cross-sectional area at the measurement point is S j 5.77m 2 , initial atmospheric pressure P 0 It is 0.1MPa.

[0021] Step 2: Calculate the volume of space between the detonation point and the pressure measurement point V t Specifically, the spatial volume can be calculated using the corresponding volume calculation formula according to the geometric shape between the detonation point and the pressure measurement point (for example, cylindrical, truncated cone, spherical, rectangular parallelepiped area, etc.); in this embodiment, the spatial volume between the detonation point and the pressure measurement point is V t 166.557m 3 .

[0022] Step 3: Measure the final inflation relative pressure value before the explosive explodes P X In this embodiment, the final inflation relative pressure value before the explosive explodes is P X It is 0.2MPa.

[0023] Step 4: Calculate the final inflation absolute pressure value before the explosive explodes P c。

[0024] In step 4, the final inflation absolute pressure value before the explosive explodes P c The calculation formula is: P c = P 0 +P X (1) In step 1 P 0 = 0.1MPa and in step 3 P X =0.2MPa Substituting into the above formula, we can get the final inflation absolute pressure value before the explosive explodes. P c It is 0.3MPa.

[0025] Step 5: Establish a table based on the corresponding relationship between atmospheric pressure and air density, as shown in Table 1, and obtain the absolute pressure value by looking up the table. P c Density of air below ρ cAccording to Table 1, the density of air at an atmospheric pressure of 0.3 MPa is 3.507 Kg / m 3 .

[0026] Table 1 Correspondence between atmospheric pressure and air density

[0027] Air densities not within the range of this table can be obtained through experiments.

[0028] Step 6, according to the charge amount Q , the cross-sectional area at the measurement point in step 1 S j 、The volume of space in step 2 V t , the final inflation absolute pressure value in step 4 P c Calculate separately S j / Q , Q / P c V t and P c V t / Q Among them, the charge Q is the total mass of explosives loaded.

[0029] According to the charge Q 0.8 Kg and in step 1 S j 5.77m 2 , calculate S j / Q is 7.213 m 2 / Kg ; According to the charge Q 、The volume of space in step 2 V t 166.557m 3 and the final inflation absolute pressure value in step 4 P c is 0.3MPa, calculated Q / P c V t 0.016 P c V t / Q It is 62.5.

[0030] Step 7, determine the shock wave arrival time correlation coefficient.

[0031] The correlation coefficients of shock wave arrival time are a tcy 、b tcy 、c tcy The above coefficients are related to the cross-sectional form of the explosion wave simulation device, the distance from the detonation point of the explosive to the measurement point, and the absolute pressure of the gas. P c The shock wave arrival time related parameters can be obtained through experiments or numerical calculations. a tcy , b tcy is a coefficient related to the ratio of the distance from the measuring point to the detonation point and the equivalent diameter of the cross section at the measuring point; c tcy is the cross-sectional area at the detonation point S c and the cross-sectional area at the measuring point S j The coefficient related to the ratio of . It can be determined by referring to the relevant technical solutions in the field, and will not be described in detail here.

[0032] The shock wave arrival time correlation coefficient at this point in the blast wave simulation device has been obtained through experiments. a tcy 、b tcy 、 c tcy They are 6.02×10 -4 , -0.0017, 22.287.

[0033] Step 8: Calculate the shock wave arrival time using the relevant formula based on the values ​​calculated in steps 1 to 7. t c .

[0034] In step 8, the shock wave arrival time calculation formula under high pressure conditions is: (2) Substituting the relevant parameters in steps 1 to 7 into the above formula, the shock wave arrival time can be obtained: t c It is 55.6ms.

[0035] The parts not described in detail in the present invention are prior art and will not be described in detail here.

[0036] On the other hand, the present invention also provides a system for calculating the arrival time of explosion shock waves under high-pressure gas conditions, which is used to execute the above-mentioned method for calculating the arrival time of explosion shock waves under high-pressure gas conditions, comprising: A data acquisition module is used to obtain the cross-sectional area at the measuring point, the initial atmospheric pressure, the final relative pressure value of the explosive before explosion, and the spatial volume between the detonation point and the pressure measurement point; An inflation absolute pressure value and air density determination module is used to determine the final inflation absolute pressure value and the corresponding air density before the explosion of the explosive based on the initial atmospheric pressure and the final inflation relative pressure value before the explosion of the explosive; A correlation coefficient determination module, used to determine the shock wave arrival time correlation coefficient; The shock wave arrival time calculation module is used to calculate the shock wave arrival time under high pressure conditions based on the cross-sectional area at the measuring point, the spatial volume, the final inflation absolute pressure value before the explosive explodes and its corresponding air density, and the shock wave arrival time correlation coefficient.

[0037] Based on dimensional analysis, the present invention proposes an engineering calculation method for the arrival time of explosion shock waves under high-pressure gas conditions, which can provide technical support for the timing control of high-pressure gas release, the calculation of shock wave velocities in air of different densities, and the design of application experiments.

[0038] The remaining technical features in the above embodiments can be flexibly selected by those skilled in the art according to actual conditions to meet different specific practical needs. However, it is obvious to those skilled in the art that it is not necessary to adopt these specific details to implement the present invention. In other examples, in order to avoid confusing the present invention, the well-known components, structures or parts are not specifically described, which are all within the technical protection scope defined by the technical solution claimed for protection in the claims of the present invention.

[0039] Modifications and changes made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the scope of protection of the claims attached to the present invention. In the above description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is obvious to those of ordinary skill in the art that these specific details are not necessary to practice the present invention. In other examples, in order to avoid confusing the present invention, well-known technologies, such as specific construction details, operating conditions and other technical conditions, are not specifically described.

[0040] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for calculating the arrival time of explosion shock waves under high pressure gas conditions, characterized in that: The following steps are involved: S1, obtain the cross-sectional area at the measuring point, the initial atmospheric pressure, and the final relative pressure of the explosive before explosion. 、 The volume of space between the detonation point and the pressure measurement point; S2, determining the final inflation absolute pressure value before the explosion of the explosive and its corresponding air density based on the initial atmospheric pressure and the final inflation relative pressure value before the explosion of the explosive; S3, determine the shock wave arrival time correlation coefficient; S4, calculating the shock wave arrival time under high pressure conditions based on the cross-sectional area at the measuring point, the spatial volume, the final inflation absolute pressure value of the explosive before explosion and its corresponding air density, the shock wave arrival time correlation coefficient and the charge amount.

2. The method for calculating the arrival time of explosion shock waves under high pressure gas conditions according to claim 1, characterized in that: The S1, obtaining the cross-sectional area at the measuring point, the initial atmospheric pressure, the final inflation relative pressure value before the explosive explodes, and the spatial volume between the detonation point and the pressure measuring point, specifically includes: Measure the cross-sectional area at the measuring point S j , initial atmospheric pressure P 0 ; Calculate the volume of the space between the detonation point and the pressure measurement point V t ; Measure the final relative pressure of the explosive before explosion P X。 3. The method for calculating the arrival time of explosion shock waves under high pressure gas conditions according to claim 2, characterized in that: The step S2, based on the initial atmospheric pressure and the final relative pressure of the explosive before the explosion, determines the final absolute pressure of the explosive before the explosion and the corresponding air density, specifically includes: Based on initial atmospheric pressure P 0 , Final inflation relative pressure value before explosive explosion P X , determine the final inflation absolute pressure value before the explosive explodes P c , the expression is as follows: P c =P 0 +P X （1） According to the corresponding relationship between atmospheric pressure and air density, the final inflation absolute pressure value is obtained. P c The corresponding air density ρ c。 4. The method for calculating the arrival time of explosion shock waves under high pressure gas conditions according to claim 3, characterized in that: The final inflation absolute pressure value is obtained according to the corresponding relationship between atmospheric pressure and air density. P c The corresponding air density ρ c , specifically including: A table is established based on the corresponding relationship between atmospheric pressure and air density, and the final inflation absolute pressure value is obtained by table lookup method. P c The corresponding air density ρ c。 5. The method for calculating the arrival time of explosion shock waves under high pressure gas conditions according to claim 3, characterized in that: The step S3, determining the shock wave arrival time correlation coefficient, specifically includes: Based on the cross-sectional form of the explosion wave simulation device, the distance from the detonation point of the explosive to the measurement point, and the final inflation absolute pressure value P c , the shock wave arrival time correlation coefficient is obtained by experiment or numerical calculation a tcy 、b tcy 、c tcy。 6. The method for calculating the arrival time of explosion shock waves under high pressure gas conditions according to claim 5, characterized in that: The step S4, based on the cross-sectional area at the measuring point, the volume of the space, the final inflation absolute pressure value of the explosive before explosion and its corresponding air density, the shock wave arrival time correlation coefficient and the charge amount, calculates the shock wave arrival time under high pressure conditions, specifically including: The calculation formula for the shock wave arrival time under high pressure conditions is as follows: （2） in, t c is the shock wave arrival time, Q For the charge amount.

7. The method for calculating the arrival time of explosion shock waves under high pressure gas conditions according to claim 6, characterized in that: In S4, formula (2) is used to calculate the time before the shock wave arrives under high pressure conditions: According to the charge Q、 Cross-sectional area at the measuring point S j , the volume of space between the detonation point and the pressure measurement point V t , Final inflation absolute pressure value before explosive explosion P c , respectively calculated S j / Q , Q / P c V t and P c V t / Q ; The calculated S j / Q , Q / P c V t and P c V t / Q Substituting into formula (2), we can obtain the shock wave arrival time under high pressure conditions: t c。

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