地下高大空间火灾烟气自由填充试验研究

Experimental analysis of the natural smoke filling in large underground space

中文关键词: 地下高大空间  烟雾填充过程  费诺德模型  模型试验  烟气层高度  火灾动力学模拟

英文关键词: Large underground space  Smoke filling process  Froude modeling  Smoke layer height  fire dynamics simulator  FDS

中文摘要:

      利用费诺德(Froude-number)相似模型理论,建立1:12的某地下高大空间（高大空间为高度大于10m,体力大于10000m3)比例模型,研究了地下高大空间火灾烟气自由填充过程及温度及浓度变化特性。1:12模型试验结果和火灾动力学模拟（Fire Dynamics Simulator，FDS)模拟值与McCaffrey预测值吻合度较高。1:12火灾模型试验能较好的预测地下大空间烟气流动特点,且是验证数值结果正确性的重要手段。试验表明,高大空间“蓄烟效应”显著,火灾发生时高大空间竖向温度呈线性分布,且温升较小,温度不是影响人员逃生和排烟效果的主要因素；火源位置处于模型的端部的烟气层下降速度慢于 中心位置。该研究为制订火灾排烟和疏散方案及高大空间防排烟规范提供了初步理论依据和第一手的试验资料。

英文摘要:

      A 1/12 scale model of a large underground space is set up according to the Froude modeling theory to investigate the characteristics of natural smoke filling in the space,thetemperature field and strength distribution. Results show that the experimental, FDS simulated values are in good agreement with each other. The fire experiments can well predict the smoke movement in large underground space, and it is feasible to verify the validity of simulated results using proportional scaling model. Because of the huge space, the “smoke storage phenomena” is very significant. The vertical temperature presents a linear distribution under fire,which suggests that smoke temperature is not the major influencing evacution and mechanical smoke extraction design. The smoke descends more slowly at the headwall than that in the center. The investigation can provide theoretical basis and experimental data for further study on mechanical smoke extraction of underground space ,and also itbenfits towork out the smoke control standard of huge space.