Research in gaseous explosion physics and prevention

拟议的研究计划将在工业爆炸安全领域进行。化工加工行业的爆炸事件屡见不鲜，该行业每年因工厂维修、收入损失和诉讼而损失数百万美元。更重要的是，大规模工业爆炸经常会造成生命损失。去年8月，多伦多日出丙烷仓库发生了一起被媒体彻底报道的气相爆炸的例子。这项工作的目的是彻底了解爆炸物理，以便防止此类爆炸。具有百万像素分辨率的超高速数字摄像机使爆炸前沿的传播速度达到每秒2000米的可视化成为可能。实验将在装有玻璃侧壁的方形横截面通道中进行，以可视化通道一端引燃的爆炸前沿的传播。爆炸锋面最初由火焰组成，但当它加速到超过爆炸性混合物的音速时，在火焰前面形成冲击波。造成结构破坏的原因是冲击波引起的压力大幅增加。一种名为纹影摄影的特殊技术将被用来捕捉爆炸前沿沿通道长度传播时的演变。参与该项目的学生将学习如何设置摄影系统并分析从实验中获得的数据。由于各种流体动力学和燃烧现象在空间和时间尺度上的巨大差异，高速爆炸传播的数值模拟仍然是一个重大挑战。然而，由于最近计算能力的重大进步，对这种复杂现象的模拟现在已经触手可及。在实验的同时，将利用皇后大学的高性能计算虚拟实验室进行计算流体力学建模，以模拟爆炸过程。实验可视化数据将被用来验证数值预测。该项目将为两名博士生和两名硕士研究生提供培训。

The proposed research program will be carried out in the field of industrial explosion safety. Explosions in the chemical process industry are common, costing the industry millions of dollars every year for plant repair, lost revenue and litigation. Even more important is the loss of life that occurs all too often with large industrial explosions. An example of a gas-phase explosion that was thoroughly covered by the media occurred this past August at the Sunrise Propane depot in Toronto. The objective of this work is to obtain a thorough understanding of explosion physics so that such explosions can be prevented. Ultra high-speed digital video cameras with megapixel resolution permit the visualization of an explosion front propagating up to a speed of 2,000 metres per second. Experiments will be performed in a square cross-section channel equipped with glass sidewalls in order to visualize the propagation of the explosion front that is ignited at one end of the channel. The explosion front initially consists of a flame, but as it accelerates to speeds in excess of the speed of sound of the explosive mixture a shock wave forms ahead of the flame. It is the large pressure increase associated with the shock wave that causes the structural damage. A special technique, known as schlieren photography, will be used to capture the evolution of the explosion front as it propagates the length of the channel. Students involved in the project will learn how to set up the photographic system and analyze the data obtained from the experiment. The numerical modeling of high speed explosion propagation remains a major challenge due to the large disparity in the spatial and temporal scales of the various fluid dynamic and combustion phenomena involved. However, as a result of recent major advancements in computing power, simulations of this complex phenomenon are now within reach. In parallel with the experiments, computational fluid dynamics modeling will be carried using the High Performance Computing Virtual Laboratory at Queen's University to simulate the explosion process. The experimental visualization data will be used to validate the numerical predictions. This program will provide training to two doctoral and two Masters students.