A Calculation Method of Shock Wave Overpressure in Pipeline Physical Explosion Considering Direction

Abstract

The invention discloses a method for calculating the overpressure of the pipeline physical explosion shock wave considering directionality. The method first assumes that the compressed gas of a cylinder with a length of kD and a diameter of D in the pipeline provides the energy for the shock wave formed by the physical explosion, and calculates the pipeline through the formula Physical explosion energy, then calculate the dimensionless distance from the target position to the explosion center, and obtain the ideal dimensionless overpressure corresponding to the target position through the Baker-Tang pressure vessel physical explosion overpressure-distance relationship diagram, and then calculate the actual dimensionless overpressure, Then the actual shock wave overpressure at the target position is obtained. This method provides a quantitative calculation method of explosion shock wave overpressure, and the calculation results are accurate.

Description

technical field [0001] Pipelines are widely used in the process industry. Pipeline physical explosion refers to the rapid rupture of the pipeline due to internal overpressure or the decrease in the strength of the pipeline itself. The internal high-pressure gas is violently released from the rupture of the pipeline, and then the external air is compressed to form a shock wave that propagates outward. The main hazards of pipeline physical explosions are shock waves, fragments and thermal radiation, among which shock waves often cause the most serious damage and have the widest range of influence. Therefore, the evaluation of the consequences of pipeline physical explosion is mainly to calculate the size distribution of shock wave overpressure in space. Background technique [0002] At present, there are two types of calculation methods for pipeline physical explosion overpressure: ① theoretical method; ② numerical simulation method. The theoretical method first calculates th...

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Problems solved by technology

There are currently two problems in the theoretical method: on the one hand, not all the compression energy of the gas in the pipeline is used to form the external shock wave, that is, when calculating the physical explosion energy of the pipeline, a certain volume of gas near the breach should be selected. At present, there is still a lack of consistent understanding and regulations; on the other hand, the data given by the existing TNT equivalent method or physical explosion overpressure-relationship diagram are all aimed at the spherical shock wave generated by the explosion of the ideal explosion source, while the data generated by the physical explosion of the pipeline The distribution of shock wave overpressure has obvious directionality. How should the existing methods be adapted when applied to the calculation of pipeline physical explosion overpressure? What is the size relationship between shock wave overpressure in different directions? How to consider, there is currently a lack of corresponding methods

[0003] For the numerical simulation method, it can calculate the shock wave overpressure more accurately, but its implementation cost is high, the professional level of personnel is high, and the calculation results will be affected by the selection of the turbulence model and the grid size. It is often necessary to verify the model before implementation, and the implementation period is long, which is not as simple and easy as the theoretical method

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