突出冲击波对风门和风筒防逆流装置的破坏研究

Failure mechanism of shock wave to anti-reflux damper and backflow prevention device of ventiduct

为了防止煤与瓦斯突出后发生瓦斯逆流,结合流体动力学研究突出冲击波对防突风门和风筒防逆流装置的破坏失效机制。基于理论推导,得到了煤与瓦斯突出条件下的冲击波传播模型,给出作用在风门和风筒防逆流装置处的反射超压。利用突出能量传播模拟系统,模拟井下发生突出事故后冲击波在巷道中的传播,并将试验结果与理论计算和数值模拟结果进行对比。在此基础上利用Fluent对4种不同突出条件下冲击波在巷道内的传播进行模拟研究,并且将风门和风筒防逆流装置处的超压随时间变化数据输入LS-DYNA进行数值模拟。研究结果表明:实际的冲击波衰减比数值模拟和理论计算更加快,试验和模拟误差不大且总的变化规律是一致的,利用数值模拟手段研究冲击波传播规律是可行的;风筒防逆流装置处的冲击波超压峰值大于风门位置的超压峰值,且冲击波超压在第1个波峰出现后震荡下降;由于风筒中反射出的冲击波叠加,风门位置的超压峰值是在第2个波峰出现,突出压力和突出孔径越大,相应的冲击波超压峰值就越大。研究成果对防突风门和防逆流装置设计具有指导意义。

In order to prevent gas backflow after outburst, failure mechanism of shock wave to backflow prevention device of ventiduct and anti-reflux damper was studied through fluid mechanics.Based on theoretical derivation, shock wave propagation model of coal and gas outburst was obtained,and reflex overpressure at anti-reflux damper and backflow prevention device of ventiduct was given.With coal and gas outburst energy propagation simulation device system, propagation of shock wave in the roadway was simulated when coal and gas outburst disasters occurred, and test results were then compared with theoretical calculation and numerical simulation results. On this basis, simulation study of propagation of shock waves in the roadway under four different outburst conditions was carried out with software Fluent, data of overpressure over time at anti-reflux damper and backflow prevention device of ventiduct were entered into LS-DYNA for numerical simulation. The results have shown that actual shock wave attenuation is faster than numerical simulation and theoretical calculation, there is not much error between experimental results and simulation, and overall trend of change is consistent. It is feasible to use numerical simulation to study propagation and attenuation of shock waves. The peak value of shock wave overpressure at backflow prevention device of ventiduct is greater than that at anti-reflux damper. Shock wave overpressure at backflow prevention device of ventiduct oscillated down after first crest appears, but shock wave overpressure peak at anti-reflux damper appears at second crest because of superposition of overpressure reflected by anti-backflow device of ventiduct. The larger outburst pressure and outburst aperture, the greater corresponding shock wave overpressure peak. The research results are instructive and meaningful to the design of anti-reflux damper and backflow prevention device of ventiduct.