管长对带弯头管道内可燃预混气体爆炸规律及薄壁动态响应的影响研究

Study on the effects of curved pipeline length on the explosion law of combustible premixed gas and the dynamic response of thin wall

基于气云燃爆实验平台,开展了不同长度弯曲管道内丙烷-空气预混气体燃爆实验测试与分析,探索管道长度对弯曲管道内可燃气体燃爆特性及爆炸冲击波对管道薄壁加载效应的影响。实验分别采用光电传感器、压力传感器和应变传感器对管道内爆炸参数和管道薄壁的应力应变规律进行了测试,结果表明,管道越长,弯曲段两侧壁面超压和管壁最大应变越大,压力时程曲线与管道薄壁应变时程曲线具有良好的一致性;弯管一定程度上激励了火焰加速传播,火焰传播速度在90°拐点处降至最低;管道长度对管道内火焰燃爆规律的影响是整体的,管道长度越长,管内压力和火焰速度越大,最大爆炸压力出现在管道末端,冲击波对管壁的加载属于动态加载。

Based on the gas cloud deflagration experimental platform, the propane-air premixed gas blasting experiments inside curved pipelines of different length are carried out. The curved pipeline length effect on the combustible gas explosion in pipeline and the explosion shock wave effect on thinwalled pipeline loading are investigated. Photoelectric, pressure and strain sensors are used to evaluate the explosion parameters within the pipeline and the stress-strain relation of the thin-walled pipeline, respectively. The results indicate that a longer pipeline corresponds to the higher wall overpressure and the bigger maximum strain of the pipeline wall. The pressure-time curve is in good agreement with the thin-walled pipeline strain-time history curve. The curved shape of the pipeline accelerates the flame propagation to a certain extent, and the flame propagation rate decreases to the minimum value at the 90 degree inflexion. The pipeline length has global effects on the flame deflagration within the pipeline. A longer pipeline results in higher pressure and flame speed. The maximum explosion pressure appears at the end of the pipeline, and the loading of the shock wave to the pipeline wall belongs to the dynamic loading.