A Calculation Method for the Arrival Time of Explosion Shock Waves under High-Pressure Gas Conditions

Abstract

The present invention relates to the technical field of prediction of explosion shock wave arrival time, and discloses a method for calculating the explosion shock wave arrival time under high-pressure gas conditions, including: obtaining the cross-sectional area at the measurement point, the initial atmospheric pressure, the final relative inflation pressure value before explosive explosion, and the space volume between the initiation point and the pressure measurement point; determining the final absolute inflation pressure value before explosive explosion and its corresponding air density based on the initial atmospheric pressure and the final relative inflation pressure value before explosive explosion; determining the correlation coefficient of the shock wave arrival time; calculating the shock wave arrival time under high-pressure conditions based on the cross-sectional area at the measurement point, the space volume, the final absolute inflation pressure value before explosive explosion and its corresponding air density, and the correlation coefficient of the shock wave arrival time. The present invention can accurately calculate the shock wave arrival time, and provide technical support for determining the high-pressure gas release time, effectively coupling the high-pressure gas and the explosion energy, calculating the shock wave velocity in air with different densities, etc.

Description

Technical Field

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

[0002] Under the combined driving conditions of high-pressure gas and explosive explosion, the explosion wave simulation device can generate dynamic loads with high peak values and long durations, and can simulate various forms of shock wave loads, the dynamic loads of the external flow field during the flight of the aircraft, and the dynamic loads of the internal flow field during the separation of the mechanism. Under the combined driving conditions, the effective coupling of high-pressure gas and explosion energy is the main technical means to control the dynamic load. Therefore, the explosion shock wave arrival time is a key parameter for controlling the release of high-pressure gas energy and the form of dynamic load.

[0003] At present, domestic and foreign researchers have done a lot of basic work on the research 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 the engineering calculation method of shock wave parameters under high-pressure gas conditions. Moreover, most of the research focuses on the peak overpressure and positive pressure action time of shock waves. Under this working condition, the shock wave arrival time 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, there is a lack of research on the shock wave arrival time under high-pressure gas conditions.

[0004] As known from the above, the shock wave arrival time is crucial for determining the high-pressure energy release time, coupling the explosion energy and high-pressure gas energy, and directly affects the simulation of different forms of dynamic loads. Therefore, accurately predicting the shock wave arrival time is of great significance for the successful simulation test of the explosion wave simulation device. For the explosion shock wave arrival time under high-pressure gas conditions, the existing technology lacks effective engineering calculation methods, and it is urgent for those skilled in the art to conduct in-depth research. Summary of the Invention

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

[0006] To achieve the above object, the present invention provides the following solution:

[0007] A method for calculating the explosion shock wave arrival time under high-pressure gas conditions, the method comprising the following steps:

[0008] S1. Obtain the cross-sectional area at the measurement point, the initial atmospheric pressure, and the final relative inflation pressure value before the explosive explosion. 、 The space volume between the detonation point and the pressure measurement point;

[0009] S2. Based on the initial atmospheric pressure and the final relative inflation pressure value before the explosive explosion, determine the final absolute inflation pressure value before the explosive explosion and its corresponding air density.

[0010] S3. Determine the correlation coefficient of the shock wave arrival time;

[0011] S4. Based on the cross-sectional area at the measurement point, the space volume, the final absolute inflation pressure value before the explosive explosion and its corresponding air density, the correlation coefficient of the shock wave arrival time, and the charge amount, calculate the shock wave arrival time under high pressure conditions.

[0012] Further, for the said S1, obtaining the cross-sectional area at the measurement point, the initial atmospheric pressure, the final relative inflation pressure value before the explosive explosion, and the space volume between the detonation point and the pressure measurement point, specifically includes:

[0013] Measure the cross-sectional area at the measurement point S j , the initial atmospheric pressure P 0 ;

[0014] Calculate the space volume between the detonation point and the pressure measurement point V t ;

[0015] Measure the final relative inflation pressure value before the explosive explosion P X。

[0016] Further, for the said S2, based on the initial atmospheric pressure and the final relative inflation pressure value before the explosive explosion, determining the final absolute inflation pressure value before the explosive explosion and its corresponding air density, specifically includes:

[0017] Based on the initial atmospheric pressure P 0 , the final relative inflation pressure value before the explosive explosion P X , determine the final absolute inflation pressure value before the explosive explosion P c , the expression is as follows:

[0018] P c = P 0 +P X (1)

[0019] According to the corresponding relationship between atmospheric pressure and air density, the final absolute inflation pressure value is obtained P c The corresponding air density ρ c。

[0020] Furthermore, the step of obtaining the final absolute inflation pressure value according to the corresponding relationship between atmospheric pressure and air density P c The corresponding air density ρ c , specifically includes:

[0021] Establish a table according to the corresponding relationship between atmospheric pressure and air density, and obtain the final absolute inflation pressure value by means of a table lookup method P c The corresponding air density ρ c。

[0022] Furthermore, step S3 of determining the shock wave arrival time correlation coefficient specifically includes:

[0023] Based on the cross-sectional form of the explosion wave simulation device, the distance from the explosive initiation point to the measurement point, and the final absolute inflation pressure value P c , obtain the shock wave arrival time correlation coefficient through experiments or numerical calculations a tcy 、b tcy 、c tcy , where a tcy 、 b tcy is a coefficient related to the ratio of the distance from the measurement point to the initiation point to the equivalent diameter of the cross-section at the measurement point; c tcy is a coefficient related to S c the cross-sectional area at the initiation point S j and the cross-sectional area at the measurement point

[0024] Furthermore, step S4 of calculating the shock wave arrival time under high pressure based on the cross-sectional area at the measurement point, the spatial volume, the final absolute inflation pressure value before the explosive explosion and its corresponding air density, the shock wave arrival time correlation coefficient, and the charge amount specifically includes:

[0025] The calculation formula for the shock wave arrival time under high pressure is as follows:

[0026] (2)

[0027] Among them, t c is the shock wave arrival time, Q is the charge amount.

[0028] Further, in the step S4, before calculating the shock wave arrival time under high pressure using formula (2), according to the charge amount Q、 the cross-sectional area at the measurement point S j the space volume between the initiation point and the pressure measurement point V t the final absolute pressure value of the air filling before the explosive explodes P c , calculate respectively S j / Q , Q / P c V t and P c V t / Q ;

[0029] Substitute the calculated S j / Q , Q / P c V t and P c V t / Q into formula (2) to obtain the shock wave arrival time under high pressure t c。

[0030] According to the specific embodiments provided by the present invention, the method for calculating the arrival time of the explosion shock wave under high-pressure gas conditions provided by the present invention discloses the following technical effects:

[0031] Comprehensively consider multiple factors affecting the arrival time of the explosion shock wave, such as the cross-sectional area at the measurement point, the space volume, the final absolute pressure value of the air filling before the explosive explodes and its corresponding air density, the shock wave arrival time correlation coefficient, etc., and accurately calculate the arrival time of the explosion shock wave;

[0032] Among them, based on the initial atmospheric pressure and the final relative inflation pressure value before the explosive explosion, the final absolute inflation pressure value before the explosive explosion and its corresponding air density are accurately determined, and parameters related to the arrival time of the shock wave, which are closely related to the cross-sectional form of the explosion wave simulation device, the distance from the explosive initiation point to the measurement point, and the absolute inflation pressure value, are combined. Under high-pressure gas conditions, research on the arrival time of the shock wave for different air densities is realized, the calculation scheme is optimized, the calculation steps are simplified, and the arrival time of the explosion shock wave is obtained quickly and accurately, which can provide technical support for the timing control of high-pressure gas release, the calculation of the shock wave velocity in air with different densities, and the application test design. Description of the Drawings

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0034] Figure 1 It is a flowchart of the method for calculating the arrival time of the explosion shock wave under high-pressure gas conditions provided by the embodiment of the present invention. Detailed Embodiments

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0036] The purpose of the present invention is to provide a method for calculating the arrival time of the explosion shock wave under high-pressure gas conditions. Aiming at the lack of research on the arrival time of the shock wave under high-pressure gas conditions in the prior art, an efficient and simple calculation scheme is proposed to accurately calculate the arrival time of the explosion shock wave under high-pressure gas conditions, so as to provide technical support for determining the high-pressure gas release time, effectively coupling the high-pressure gas and the explosion energy, calculating the shock wave velocity in air with different densities, and the application test design.

[0037] In order to make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0038] The method for calculating the arrival time of the explosion shock wave under high-pressure gas conditions provided by the present invention includes the following steps:

[0039] S1. Obtain the cross-sectional area at the measurement point, the initial atmospheric pressure, the final relative inflation pressure value before the explosive explosion, and the space volume between the initiation point and the pressure measurement point;

[0040] S2. Based on the initial atmospheric pressure and the final relative inflation pressure value before the explosive explosion, determine the final absolute inflation pressure value before the explosive explosion and its corresponding air density;

[0041] S3. Determine the correlation coefficient related to the shock wave arrival time;

[0042] S4. Based on the cross-sectional area at the measurement point, the space volume, the final absolute inflation pressure value before the explosive explosion and its corresponding air density, the correlation coefficient related to the shock wave arrival time, and the charge amount, calculate the shock wave arrival time under high-pressure conditions.

[0043] As Figure 1 shown, in the embodiment of the present invention, taking a certain explosion wave simulation device as an example, the charge amount is 0.8 Kg TNT. The calculation method of the explosion shock wave arrival time under high-pressure gas conditions of this explosion wave simulation device specifically includes the following steps:

[0044] Step 1. Measure the cross-sectional area at the measurement point S j , the initial atmospheric pressure P 0 . This embodiment is carried out on a certain explosion wave simulation device. The cross-sectional area at the measurement point S j is 5.77 m 2 , and the initial atmospheric pressure P 0 is 0.1 MPa.

[0045] Step 2. Calculate the space volume between the initiation point and the pressure measurement point V t . Specifically, the space volume can be calculated according to the geometric shape between the initiation point and the pressure measurement point (for example, cylindrical, frustum-shaped, spherical, cuboid area, etc.) using the corresponding volume calculation formula; in this embodiment, the space volume between the initiation point and the pressure measurement point V t is 166.557 m 3 .

[0046] Step 3. Measure the final relative inflation pressure value before the explosive explosion P X . In this embodiment, the final relative inflation pressure value before the explosive explosion P X is 0.2 MPa.

[0047] Step 4. Calculate the final absolute inflation pressure value before the explosive explosion Pc。

[0048] In step 4, the final absolute pressure value of inflation before the explosive explodes P c The calculation formula is:

[0049] P c = P 0 +P X (1)

[0050] Substitute = 0.1 MPa in step 1 P 0 and = 0.2 MPa in step 3 P X into the above formula, and the final absolute pressure value of inflation before the explosive explodes can be obtained P c is 0.3 MPa.

[0051] Step 5, establish a table according to the corresponding relationship between atmospheric pressure and air density, as shown in Table 1. Through the table lookup method, obtain the air density P c under ρ c . According to Table 1, the air density under the atmospheric pressure of 0.3 MPa can be found to be 3.507 Kg / m 3 .

[0052] Table 1 Corresponding relationship table between atmospheric pressure and air density

[0053]

[0054] For the air density outside the range of this table, it can be obtained through experiments.

[0055] Step 6, according to the charge amount Q , the cross-sectional area S j at the measurement point in step 1 V t , the space volume P c in step 2 S j / Q , Q / P c V t and P c V t / Q. Among them, the charge amount Q is the total mass of the loaded explosive.

[0056] According to the charge amount Q being 0.8 Kg and that in Step 1 S j being 5.77 m 2 , calculate S j / Q is 7.213 m 2 / Kg ; according to the charge amount Q , the spatial volume in Step 2 V t being 166.557 m 3 and the final absolute pressure value of inflation in Step 4 P c being 0.3 MPa, calculate Q / P c V t being 0.016, P c V t / Q being 62.5.

[0057] Step 7, determine the correlation coefficient of the shock wave arrival time.

[0058] The correlation coefficients of the shock wave arrival time are respectively a tcy 、b tcy 、c tcy . The above coefficients are closely related to the cross-sectional form of the explosion wave simulation device, the distance from the explosive initiation point to the measurement point, and the absolute pressure value of inflation P c . The relevant parameters of the shock wave arrival time can be obtained through experiments or numerical calculations, etc. Specifically, a tcy , b tcy is a coefficient related to the ratio of the distance from the measurement point to the initiation point and the equivalent diameter of the measurement point cross-section; c tcy is a coefficient related to the ratio of the cross-sectional area at the initiation point S c and the cross-sectional area at the measurement point S j . It can be determined by referring to the relevant technical solutions in this field and will not be elaborated here.

[0059] The correlation coefficient of the shock wave arrival time at this point in the explosion wave simulation device has been obtained through experiments. a tcy 、b tcy 、 c tcy They are 6.02×10 -4 、 -0.0017, and 22.287 respectively.

[0060] Step 8: According to the values calculated in Steps 1 to 7, use the relevant formula to calculate the shock wave arrival time. t c .

[0061] In the said Step 8, the calculation formula for the shock wave arrival time under high-pressure conditions:

[0062] (2)

[0063] Substitute the relevant parameters in Steps 1 to 7 into the above formula, and the shock wave arrival time t c is 55.6 ms.

[0064] The parts not detailed in the present invention are prior arts and will not be elaborated here.

[0065] On the other hand, the present invention also provides a calculation system for the shock wave arrival time under high-pressure gas conditions, which is used to execute the above-mentioned calculation method for the shock wave arrival time under high-pressure gas conditions, including:

[0066] A data acquisition module, which is used to acquire the cross-sectional area at the measurement point, the initial atmospheric pressure, the final relative inflation pressure value before the explosive explodes, and the space volume between the initiation point and the pressure measurement point;

[0067] An absolute inflation pressure value and air density determination module, which is used to determine the final absolute inflation pressure value before the explosive explodes and its corresponding air density based on the initial atmospheric pressure and the final relative inflation pressure value before the explosive explodes;

[0068] A correlation coefficient determination module, which is used to determine the correlation coefficient of the shock wave arrival time;

[0069] A shock wave arrival time calculation module, which is used to calculate the shock wave arrival time under high-pressure conditions based on the cross-sectional area at the measurement point, the space volume, the final absolute inflation pressure value before the explosive explodes and its corresponding air density, and the correlation coefficient of the shock wave arrival time.

[0070] 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 velocity in air with different densities, and the design of application tests.

[0071] For the remaining technical features in the above embodiments, those skilled in the art can flexibly select them according to actual situations to meet different specific actual needs. However, it is obvious to those of ordinary skill in the art that these specific details do not have to be adopted to implement the present invention. In other instances, well-known components, structures, or parts are not specifically described in order to avoid obscuring the present invention, and all are within the scope of the technical solutions claimed in the claims of the present invention.

[0072] Modifications and changes made by those skilled in the art without departing from the spirit and scope of the present invention shall fall within the protection scope of the appended claims of the present invention. In the above description, numerous 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 do not have to be adopted to implement the present invention. In other instances, well-known technologies, such as specific construction details, operating conditions, and other technical conditions, are not specifically described in order to avoid obscuring the present invention.

[0073] Specific examples are used in this article to elaborate on the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, there will be changes in the specific implementation manners and application scopes according to the idea of the present invention. In summary, the content of this specification should not be construed as a limitation to 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, 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, determining the shock wave arrival time correlation coefficient, specifically including: 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 a is obtained through experiments or numerical calculations tcy 、b tcy 、c tcy , where a tcy 、b tcy c is a coefficient related to the ratio of the distance from the measuring point to the detonation point to the equivalent diameter of the cross section at the measuring point; tcy is the cross-sectional area S at the detonation point c and the cross-sectional area S at the measuring point j The coefficient related to the ratio of 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.

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 S at the measuring point j , initial atmospheric pressure P0; Calculate the volume V of the space between the detonation point and the pressure measurement point t ; Measure the final inflation relative pressure value P before the explosive explodes 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 its corresponding air density, specifically includes: Based on the initial atmospheric pressure P0, the final inflation relative pressure value P before the explosive explodes X , determine the final inflation absolute pressure value P before the explosive explodes c , the expression is as follows: P c =P0+P X (1) According to the corresponding relationship between atmospheric pressure and air density, the final inflation absolute pressure value P is obtained. 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: According to the corresponding relationship between atmospheric pressure and air density, the final inflation absolute pressure value P is obtained. c The corresponding air density ρ c , including: According to the corresponding relationship between atmospheric pressure and air density, a table is established, and the final inflation absolute pressure value P is obtained by table lookup method. 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 4, 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: Among them, t c is the arrival time of shock wave, and Q is the charge amount.

6. The method for calculating the arrival time of explosion shock waves under high pressure gas conditions according to claim 5, 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, the cross-sectional area S at the measuring point j , the volume of space V between the detonation point and the pressure measurement point t , the final inflation absolute pressure value P before the explosive explodes c , calculate 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 Substituting / Q into formula (2), we can obtain the shock wave arrival time t under high pressure conditions. c .

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