火箭发射场液氢泄漏扩散特征CFD模拟分析

Simulation and analysis of leakage and diffusion of liquefied hydrogen using CFD modeling

通过CFD软件并结合自定义函数(UDF)功能对不同工况下的液氢泄漏扩散过程进行模拟并进行分析,不同的泄漏压力、泄漏孔位置、外部来流风向对液氢泄漏扩散具有重要的影响。分析数值模拟结果表明:随着压力的增加,液氢低温危害区以及氢气可燃区面积增大;泄漏口距离地面越近,整个氢气浓度分布的可燃区面积增大;上部吹风有利于氢气的稀释进而减少泄漏危害性。

The FLUENT software CFD was used with the compilation of User Defined Function（UDF）to simulate and analyze the process of the leakage and diffusion of LH2. The different leakage pressure,leak location,external flow direction diffusion had an important influence on the hydrogen leakage. Numerical simulation results indicate that the increase of leakage pressure will lead to the increase of the area of lowtemperature hazard zone of LH2 and hydrogen combustible zone. The closer the location of the leak port is to the ground,the larger the combustible range of the whole hydrogen concentration distribution will be. The upper blow is the most favorable way to dilute the concentration of hydrogen and to reduce the harm of leakage.