摘要
为研究机舱火灾烟气蔓延的特点,进行了全尺寸机舱火灾烟气填充试验,在试验舱室内设置4个不同尺寸的填充物,研究不规则截面舱室的烟气沉降规律,同时改变油池尺寸和抬升火源研究火源功率和火源高度对烟气温度分布和烟气层沉降的影响。结果表明：随火源功率增大,顶棚和侧墙的温度升高,烟气的沉降速率增大,当火源功率较小时顶棚温度较低,以温度为阈值的消防喷头失效;将火源抬升4 m时烟气温度及烟气沉降速率均升高,但烟气层稳定在8 m高度,舱室底部形成一个相对安全的空间。另外,基于Zukoski羽流模型和质量守恒,推导出不规则截面烟气沉降理论预测模型,与前人的模型对比,该理论模型预测值更接近实际观测值。
This paper intends to study the fire smoke filling process in the ship-engine room based on theoretical analysis and full-scale tests.In the ship-engine room,there are many pipes and tanks to take up space,which will affect the smoke filling process.The existing smoke filling models didn＇t consider this influence.Based on the Zukoski plume model and mass conversation,we developed a new model to predict the smoke layer descending in a room with irregular cross-sections.Then we built a full-scale ship-engine room model,with the size of 22 m（length） ×12 m（width） × 14 m（high）.To simulate the impact of the fuel pipelines and the storage tanks,we filled up four different obstacles according their real sizes in the model.Four sets of tests with different fire sizes were conducted to study the influence of heat release rate to smoke filling,and another test with the fire height of 4 m was conducted to simulate the influence of fire position.The results showed the smoke temperature in the engine room increased with the increasing of the fire size,and the smoke descending rate increased with the increasing of the fire size.When the fire sizes were 0.5 m2 and 1 m2,the smoke temperature of the ceiling was too low to activate the sprayer.When the fire source was lifted up to 4 m,the ceiling temperature rose obviously to the temperature to activate the sprayer.With the raise of fire source position,the height of the smoke entrainment reduced,and the smoke entrainment volume decreased,the smoke layer tended to be descending slowly down and then kept at about 8 m high.So lifting the fire source is beneficial to the staff members or occupants to evacuate.Compared with the results of models and tests,the model deduced in this paper was closer to the experimental results,it can be expected more accurate than the previous ones on predicting the time of smoke layer descending in rooms with irregular cross-sections.
作者
李元洲
刘义
LI Yuan-zhou;LIU Yi(State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026, Chin)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2018年第2期542-547,共6页
Journal of Safety and Environment
基金
科技部国家重点实验室基本业务费项目
关键词
安全工程
全尺寸机舱
烟气填充
不规则截面
火源功率
预测模型
safety engineering
full-scale engine room
smokefilling
irregular cross section
fire power
prediction model
