Behavior of hot airflow heated by a fire in a tunnel with ventilation duct.

带通风管道的隧道中被火加热的热气流的行为。

• 批准号: 06555313
• 负责人: UCHINO Kenichi
• 金额: $ 3.78万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research (B)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06555313/
• 关键词: Tunnel; Fire; Ventilation duct; CFD; Model experiment; 火炎

The results of experiments executed in this year are as follows.1. Measurement of airflow temperature and movement during a tunnel fire in a model duct.A series of tunnel fire experiments are executed to measure precise airflow temperatures by increased number of measuring points in a model duct. Airflow in a normal and hot temperature zone was visualized by a smoke tube. There were air inflow to and outflow from the duct at the both sides of the duct when the inclination of the duct was small, that is, heated air came out at the upper part of the duct and cold air flew in at the lower part of the duct. There observed only inflow of air at the lower side of the duct when the inclination was large. There ware discontinuity in the air temperature at the downwind of the fire and highly disturbed air flow was also observed by the visualization.2. Actual size fire experiments in an inclined shaft.Actual size fire experiments were executed in an inclined shaft at the National Institute of Resources and Environment, Kyushu Coal Mining Research Center. Behavior of hot airflow heated by a fire was observed during upwind and downwind conditions. The airflow continued to flow downward even during the fire when initial air velocity was more than 1.7m/s. This result was not expected one, however, it will be very useful if another tunnel fire experiments will be done using different inclination.3. Development of a computer program to simulate a fire in a tunnelThe program was developed to be able to simulate gas diffusion and exhaust ventilation system. However, it requires to resolve the long computation time and large memory requirement.

今年的实验结果如下： 1．测量模型管道中隧道火灾期间的气流温度和运动。执行一系列隧道火灾实验，通过增加模型管道中的测量点数量来测量精确的气流温度。通过烟管可视化常温区和高温区的气流。当风道倾角较小时，风道两侧有空气流入和流出风道，即热风从风道上部流出，冷风从风道下部流入。当倾斜度较大时，仅观察到空气在管道下侧流入。可视化还观察到火灾下风向处的气温存在不连续性，气流受到高度扰动。2．斜井实际尺寸火灾实验。斜井实际尺寸火灾实验是在国立资源环境研究所九州煤矿研究中心的斜井中进行的。在逆风和顺风条件下观察了被火加热的热气流的行为。即使在火灾过程中，当初始风速大于1.7m/s时，气流仍继续向下流动。这一结果是出乎意料的，但是，如果使用不同的倾角进行另一次隧道火灾实验，将会非常有用。 3．开发模拟隧道火灾的计算机程序该程序能够模拟气体扩散和排气通风系统。然而，它需要解决较长的计算时间和较大的内存需求。