应用FDS建立建筑外墙开口溢流火灾研究数值模型,采用非稳态t2火模型设计6种工况,对比分析窗槛墙和防火挑檐的阻隔性能,结果表明,窗槛墙高度1、1.2m时温度分布情况和0.8m时较类似；随防火挑檐宽度增加,阻隔作用更加明显；窗槛墙和防火挑檐使得除着火层外各层辐射强度均较低.通过小尺寸实验研究防火挑檐对竖向火焰的阻隔性能,结果表明,着火层上方温度随防火挑檐宽度增加而变低,但防火挑檐达到一定宽度后着火层上层卷吸增强,致使温度升高.%A numerical model of building exterior wall openings overflow fire was built by FDS. The non-steady-state t2 fire scenario was utilized and 6 simulation conditions were designed. The blocked performances of windowsill wall and fire canopywere compared and analyzed. Results showed that the temperature distribution when the windowsill wall was 1, 1. 2 m high were similar to that when the height was 0,8 mj the blocked performance was better when the fire canopy was wider. The windowsill wall and the fire canopy can depress the radiation to floors without fire. The blocked performance of fire canopy to vertical fire spread was studied by small scale experiment, and results showed that the temperature above the floor on fire decrease with the fire canopy gets wider, but when the weight reach a limit, the entrainment would be strength and increase the temperature.
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