Study On The Damage Characteristics Of Gas Explosion Shock Wave In Pipeline Network

As the roadway structure becomes more and more complex,the number of blind alleys and one-eyed wells increases,resulting in an increase in the probability of gas explosion accidents.Aiming at the problem of damage caused by gas explosion shock wave to ventilation equipment and other structures in the roadway,the method of combining theoretical analysis,laboratory experiment and numerical simulation is used to carry out the research on the damage characteristics of the gas explosion shock wave of the pipe network,which is of great significance to the anti-explosion design of the ventilation equipment in the mine roadway.The main research results are as follows:Through the experimental study of the damage characteristics of the shock fluctuation force of the gas explosion in the pipe network,the pressure peak at the pressure measurement point A and the pressure peak at the pressure measurement point B in the gas pipe network explosion experiment are 0.496 MPa,which is basically the same as the pressure peak at the same position simulated,which verifies the accuracy of the simulation experiment.Under the impact load of the same strength,due to the existence of the beveled pipe,the impact strength of the damper at position B is greater than that at position A,and the maximum strain value at B is 1.33 times that of A.The time for the damper to reach the maximum strain value at position B is approximately10.9ms,and the time for the damper at position A to reach the maximum strain value is approximately 6.3ms.After the loading of the front shock wave of the damper of different materials,the unloading rate of the unloading wave is different,which is specifically manifested as concrete material> steel material > aluminum alloy material.By using LS-DYNA finite element software and multi-material ALE finite element method,the failure characteristics of gas explosion shock fluctuation force of pipeline network are simulated and studied,and the dynamic response of obstacles in the pipe network system is studied on the basis of verifying the calculation model,considering the brittle failure of materials,and the failure characteristics of dampers and windows of different materials under the action of gas explosion shock wave are realized,and numerical simulation results consistent with the experimental results are obtained.When the gas explodes in the pipe network,the area where the stress concentration of the damper and the wind window is distributed is the center area of the air window,the two corners of the damper constraint end,and the center position of the constraint end.When the gas explosion shock wave acts on the damper and the wind window,the main area of stress concentration is the entire constraint end of the damper,and the stress value shows a decreasing trend with the increase of the distance from the restraint end.With the decrease of thickness,the gap between the maximum amount of strain energy shows a decreasing trend.After the loading of the precursor shock wave of the damper of different materials,the unloading rate of the unloading wave is different,which is consistent with the conclusion obtained in the experiment.The same thickness,the same position,the overall structure composed of different materials of damper and glass material wind window,under the impact of the same level of explosion load,the impact resistance is: the structure composed of steel damper and glass material wind window is better than the structure composed of aluminum alloy material damper and glass material wind window,and finally the structure composed of concrete material damper and glass material wind window.It is of great significance to study the damage characteristics of the explosion shock fluctuation force of the pipe network for the design of ventilation structures in mine roadways and realize the effectiveness of ventilation systems in the catastrophic period.The thesis has 70 figures,10 tables and 76 references.