室内液化石油气泄漏扩散数值模拟

液化石油气是一种危险性气体,一旦发生泄漏,所造成的后果是非常严重的,所以其安全问题很重要。针对液化石油气的特点,建立有限空间内部发生泄漏扩散的物理模型,并对液化石油气泄漏扩散的过程进行了数值模拟。通过模拟结果分析了其扩散过程的内部流场,并对比了相对湿度不同时其扩散过程的变化规律。结果表明,由于受空气中涡流移动的影响,泄漏点两侧气体扩散的速度矢量由起初的一侧高另一侧低变为一侧低另一侧高;风速增大,加快涡流的产生和移动速度,使C₃H₈的质量分数分布变化更剧烈;相对湿度较大时气体的下降速度比湿度小时更快,在低于泄漏点高度的平面内,湿度增大,C₃H₈的质量分数也变大,缩短液化石油气报警器的报警时间。

Numerical Simulation of Leakage and Diffusion of Indoor Liquefied Petroleum Gas

Liquefied petroleum gas belongs to dangerous gas, once the leakage occurs, the consequences are serious. So its security problem is very important. According to the characteristics of LPG leakage, a physical model of leakage and diffusion in the limited space was established, and the diffusion process of the gas leakage was simulated. The internal flow field of the diffusion process was analyzed through simulation results, and the different of the diffusion processes were compared under the different relative humidity. The results showed that due to the moving eddy in the air, the velocity vector of the gas diffusion change from one side was higher than the other side to the other side was higher. The increase of wind speed would accelerate the generation and movement of the eddy, and the concentration distribution of C₃H₈ would change acutely. When the air relative humidity increased, the gas descended faster, and in the plane below the leakage point, the humidity increased, the concentration ofC₃H₈ was higher, the alarm time of the liquefied petroleum gas alarm device would be shortened.