有障碍物空间可燃气体扩散规律的数值模拟

有限空间内可燃气体泄漏扩散容易引发危险事故,而对于有限空间障碍物存在时气体泄漏扩散规律的研究较少。为此,针对有限空间障碍物对可燃气体泄漏扩散的影响,采用雷诺平均的N-S方程,湍流模型以及无反应多组分输运方程,对障碍物影响下可燃气体泄漏扩散进行了数值模拟,并进一步分析了泄漏位置和障碍物高度对可燃气体泄漏扩散的影响。结果表明:障碍物对可燃气体扩散过程有阻碍作用;障碍物影响下不同位置泄漏扩散形成的浓度场不同,泄漏口与出口异侧,距离障碍物越近,房间内形成的爆炸区域越大;障碍物高度越高,有限空间内形成的爆炸区域越大,增大了危险事故发生的可能性。该模拟结果有助于室内燃气管道安全设计,可为制订室内可燃气体爆炸事故的预防措施提供参考。

Numerical simulation of combustible gas diffusion in the confined room with obstacles

Dangerous accidents will easily occur due to the leakage and diffusion of combustible gases in a confined room. In view of this, we adopted the averaged Navier Stokes equation by the Reynolds, the  turbulence model, and the unresponsive multi component transport equation to numerically simulate the leakage and diffusion of combustible gases under the influence of obstacles in a confined room in order to obtain the influence of obstacles on leakage and diffusion and furthermore analyzed the influence of leakage position and the obstacle's height on leakage and diffusion of combustible gas. The simulation results show that ①the obstacles can block the diffusion of combustible gases, ②the diffused gases will form different concentration fields at different positions due to the obstacles, ③when the leakage hole is opposite to the outlet, the nearer the distance between the obstacle and the leakage hole, the bigger the burst area in the confined room, and ④the bigger the height of the obstacle, the bigger the burst area within the finite space, resulting in bigger possibility of hazards. The simulation results not only contribute to safety design of indoor gas pipes, but provide reference for designers to take preventive measures against explosion accidents of indoor combustible gases.