摘要
特长公路隧道火灾烟气控制是隧道火灾防治的热点及难点问题之一。采用隧道内烟气温度、浓度、压力以及烟气控制范围等静态指标无法综合评估隧道通风排烟时的烟气控制效果,而且存在较高的偶然性和误差率。根据相似理论,搭建了1∶10缩尺寸隧道火灾试验模型,开展了单向排烟和双向排烟模式下20组隧道火灾模型试验,各试验工况下排烟风机处火灾烟气温度随时间呈线性增长趋势,因此将排热效率λ作为评价集中排烟模式下烟控效果的关键参数。结果表明：当排烟阀设置方案相同时,双向排烟模式下的排热效率比单向排烟模式提高5%~10%;排烟阀面积为4~6m2,开启个数为4、6时,排热效率较高。
The paper is aimed at presenting the results of our experimental study on the heat exhausting efficiency under the central exhaust mode prone to tunnel fire.In order to improve our understanding of heat exhaust regularity,we have built up a 1：10 reduced-scale tunnel fire experimental model based on the similarity theory,and,in turn,we have carried out 20 different tests under the unidirectional smoke exhaust mode and bidirectional smoke exhaust mode.In addition,we have laid out a set of ventilating numbers in a sequential form of 4,6,8,12,in the respective ventilation areas of 2.5,4,6,8,with the corresponding spaces of 25,50,75 while taking into full account the whole tunnel construction features.To make our experimental study more purposeful in a form of a reduced-scale,we have set about a rule of a linear increasing trend in the smoke temperature against the time in different conditions,so as to turn the heat exhaust efficiency λ into the key parameter for evaluating the smoke control efficiency in the central exhausting system.The results of our experimental study shows that the main factors influencing the heat exhaust efficiency are the area of individual ventilators,the total area of open-up ventilators and the opening range of the ventilators at a definite smoke exhausting rate,when the heat exhausting efficiency of bidirectional smoke exhaust mode tends to increase by 5%-10% in contrast with the heat exhaust efficiency of the unidirectional smoke exhaust one when the ventilator setting mode is under the same condition.However,the heat exhaust efficiency should be higher in an area with 4-6 ventilators in a ventilation of 4-6 m2.Nevertheless,the heat exhaust efficiency λ can probably lead to the disadvantages of the above static indexes,which proves to be reliable and practical.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2013年第4期156-160,共5页
Journal of Safety and Environment
基金
浙江省科技厅科技计划项目(2008C13041-2)
关键词
安全工程
集中排烟
烟气温度
排热效率
烟控效果
safety engineering
central smoke exhaust
smoke temperature
heat exhaust efficiency
smoke control effect
