构建了含弱约束面的受限空间油气爆炸模拟实验系统,对含有弱约束的受限空间油气爆炸外部特性进行了实验研究.实验获得了容器外部不同位置处爆炸超压随时间的变化规律,同时利用高速摄影系统记录了爆炸火焰发展变化过程.研究结果表明:①竖直方向和水平方向爆炸压力随时间变化规律均为“破膜与泄流正超压→最大负超压→外部爆燃正超压→二次负超压”,竖直方向上最大爆炸压力要略大于水平方向上的最大爆炸压力.②随着油气浓度的增加,爆炸超压先增大后减小,在初始油气浓度为1.79％时爆炸超压达到最大值.③随着比例距离的增大,外部爆炸超压呈负指数规律递减.④火焰形态变化过程可分为“喷射引燃阶段→卷曲变形阶段→蘑菇云状火焰阶段→衰弱熄灭阶段”,火焰最大高度为0.85 m,最大直径为0.6m.%An analog test system for explosion of fuel-air mixture in a confined space with weak constraint surfaces was established,and the external explosion characteristics of fuel-air mixture in the space was studied through tests.The relationship curves of explosion overpressure versus time at different locations outside the vessel were obtained,and the explosion flame development process was recorded with a high speed photographic system.The results showed that the characteristics of the external overpressure is "burst & effusion overpressure→maximum negative pressure → external explosion overpressure→secondary negative overpressure",the maximum overpressure value in the vertical direction is higher than that in the horizontal direction;with increase in oil gas concentration,the explosion overpressure increases firstly and then decreases,when the initial oil concentration is 1.79％,the explosion overpressure reaches the maximum value;the external explosion overpressure decreases following a negative exponential law with increase in the proportional distance;the flame morphological change process is "pilot injection stage→crimping and deforming stage→mushroom shaped stage→extinction stage",the flame's maximum height is 0.85 m and its maximum diameter is 0.6 m.
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