火灾中的木耳燃烧特性

对湖南衡阳“11．3”特大火灾事故的重要可燃物木耳，进行了小尺寸和全尺寸实验．采用两种最常见的点燃方式，即外部辐射着火和内部受热着火，点燃木耳，以便多角度研究其燃烧特性．外部辐射着火的方式采用符合ISO5660标准的小型锥形量热计来实现，测量其热释放速率及质量损失速率．实验表明，在相同的外部辐射功率下，粉状木耳比原状木耳更易点燃，而且，木耳的点燃辐射功率存在一个临界值．同时，木耳的质量损失速率不是影响其热释放速率的惟一因素．内部受热着火的方式采用符合ISO9705标准的全尺寸多功能热释放速率实验台来实现，测量包括热释放速率、质量损失速率、房间内温度场、组分浓度等多个物性参数．质量损失速率、各点温度以及产物一氧化碳浓度变化曲线均与热释放速率曲线的变化趋势保持一致．

Preliminary study on combustion characteristics of agaric in fire

The combustion characteristics of agaric,an important combustible in Hengyang '11.3' Fire in Hunan province,China,was investigated using different scale experiment equipments.Two most common ignition manners, external radiation heat and internal heat,were used to ignite the agaric.For external radiation ignition manner,a series of small-scale fire tests were conducted in a cone calorimeter in accordance with ISO 5660.Heat release rate and mass loss rate were measured.The experimental data indicate that,agaric in powder form is easier to be ignited than in its original shape under the same external irradiance power,and that there is a critical radiation value for the ignition of agaric.In addition,mass loss rate was not the only parameter influencing heat release rate in cone calorimeter for agaric.For internal heat ignition manner,a fire test was carried out in a full-scale room in accordance with ISO 9705.Multi-parameters,such as heat release rate,mass loss rate,temperature field and species concentration,were measured.The varying tendencies of mass loss rate,temperatures of each point,and CO concentration were all consistent with heat release rate.