Explosions in closed pipes containing baffles and 90 degree bends
Explosions in closed pipes containing baffles and 90 degree bends
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DOI：
10.1016/j.jlp.2009.09.004
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发表时间：
2010-03-01
影响因子：
3.5
通讯作者：
Scheider, Swen
中科院分区：
文献类型：
--
作者：
Blanchard, Robert;Arndt, Detlef;Scheider, Swen
文献中普遍缺乏关于全通径障碍物对燃烧影响的信息，这些障碍物在许多应用中普遍存在，了解它们对燃烧速率、火焰加速和滴滴涕等现象的影响对于正确放置阻火器和排气装置等防爆安全装置非常重要。在这项工作中，对 18 m 长的 DN150 封闭管道中的甲烷、丙烷、乙烯和氢气-空气爆炸进行了研究，该管道具有 90 度弯头，并在距离点火源不远的地方放置了各种挡板障碍物。在使用相同配置进行多次实验后，发现测量的火焰速度和超压存在相对较大的差异，这归因于火焰如何演化以及它们如何引起湍流并与湍流相互作用以产生火焰加速的随机因素。这导致对一种配置进行多次实验以获得有意义的平均值。结果表明，长管中的 90 度弯曲能够提高火焰速度和超压，并不同程度地缩短多种气体达到 DDT 的上升距离。就对这些参数的定性影响而言，它们与阻塞率在 10% 至 20% 之间的挡板型障碍物相当。 (C) 2009 年，爱思唯尔有限公司出版。
There is a general lack of information on the effects of full-bore obstacles on combustion in the literature, these obstacles are prevalent in many applications and knowledge of their effects on phenomena including burning rate, flame acceleration and DDT is important for the correct placing of explosion safety devices such as flame arresters and venting devices. In this work methane, propane, ethylene and hydrogen-air explosions were investigated in an 18 m long DN150 closed pipe with a 90 degree bend and various baffle obstacles placed at a short distance from the ignition source. After carrying out multiple experiments with the same configuration it was found that a relatively large variance existed in the measured flame speeds and overpressures, this was attributed to a stochastic element in how flames evolved and also how they caused and interacted with turbulence to produce flame acceleration. This led to several experiments being carried out for one configuration in order to obtain a meaningful average. It was shown that a 90 degree bend in a long tube had the ability to enhance flame speeds and overpressures, and shorten the run-up distance to DDT to a varying degree for a number of gases. In terms of the qualitative effects on these parameters they were comparable to baffle type obstacles with a blockage ratios of between 10 and 20%. (C) 2009 Published by Elsevier Ltd.