Spotting ignition of larch(Larix gmelinii)fuel bed by different firebrands  

作　　者：Guang Yang Jibin Ning Lifu Shu Jili Zhang Hongzhou Yu Xueying Di 

机构地区：[1]School of Forestry,Northeast Forestry University,Harbin 150040,People’s Republic of China [2]Key Laboratory of Forest Protection,Research Institute of Forest Ecology,Environment and Protection,Chinese Academy of Forestry,State Forestry Administration,Beijing 100091,People’s Republic of China [3]Research Centre of Cold Temperate Forestry,Chinese Academy of Forestry,Harbin 150086,People’s Republic of China

出　　处：《Journal of Forestry Research》2022年第1期171-181,共11页林业研究（英文版）

基　　金：funded by the Sub topic of 13th Five-Year-Plan National Key Research and Development Project(2017YFD0600106-2);National Natural Science Foundation Project(31,400,551,31,870,644)。

摘　　要：Spot fire increase the difficulty of fire-fighting and threaten public safety,and therefore it is important to study ignition probabilities of fuel bed by different firebrands,in order to understand ignition mechanisms and analyze the formation of spot fires.This will provide an important basis for further study to improve the fire-fighting efficiency and reduce casualties.In this study,the ignition probabilities of larch(Larix gmelinii)fuel beds with different moisture levels and packing ratios by diffreent firebrands,including cones and twigs of different sizes,was investigated.Ignition experiments were conducted at different wind speeds generated by fans.The results show that,regardless of moisture content and packing ratio,ignition probability is zero when there is no wind.Both moisture content and wind speed significantly infuence ignition probability,while packing ratio has almost no effect.The maximum moisture content at which firebrand ignition occurred was 50%,and ignition probability increased with wind speed and decreased with moisture content.Cones have the highest ignition probability,followed by large twigs and by small twigs.Ignition probability is also affected by firebrand shapes and sizes that determine their potential heat and contact area to the fuel bed.Two empirical models were established to link ignition probability with fuel properties and wind speed.This study will help clarify the mechanism of spot ignition and reduce corresponding losses.

关 键 词：Firebrands Wind speed Moisture content Packing ratio Logistic model Larix gmelinii 

分 类 号：S762.1[农业科学—森林保护学]