聚光阴燃点火的特性:实验和模拟  

Smoldering Ignition Characteristics by Concentrated Solar Irradiation:Insight from Experimental and Numerical Study

作　　者：林少润 王思言 孙培艺 袁晗 黄鑫炎 Lin Shaorun;Wang Siyan;Sun Peiyi;Yuan Han;Huang Xinyan(Research Centre for Fire Safety Engineering,The Hong Kong Polytechnic University,Hong Kong 999077,China;Shenzhen Research Institute,The Hong Kong Polytechnic University,Shenzhen 518057,China)

机构地区：[1]香港理工大学消防安全工程研究中心,中国香港999077 [2]香港理工大学深圳研究院,深圳518057

出　　处：《燃烧科学与技术》2023年第4期390-396,共7页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(51876183).

摘　　要：阳光经汇聚后形成的光斑可点燃常见的可燃物,是生活中潜在的火灾风险,威胁人们的生命和财产安全.本文首先通过小尺度实验研究了多层薄纸在汇聚阳光下的阴燃点火现象.实验将直射的太阳光通过一个直径为150 mm、焦距为108 mm的玻璃球汇聚后作用在燃料上,并在焦距范围内通过改变薄纸的位置以控制光斑的直径大小(1.5~20.0 mm).实验发现:随着光斑直径减小,燃料内部热传导散热的影响增强,点火所需的临界辐射热通量增大.然后,研究进一步基于开源代码Gpyro建立了阴燃点火和火蔓延的二维模型,成功再现实验现象并验证实验结果.本文量化了太阳聚光后的火灾风险,以期对未来的火灾防护工作提供一定的参考意义和科学指导.The concentrated solar irradiation spot can ignite common fuels,which is a potential fire risk that threatens the safety of people’s life and properties.In this work,small-scale experiments were performed to investigate the smoldering ignition of multi-layer tissue paper using concentrated solar irradiation spots.The sunlight was concentrated through a transparent glass sphere with a diameter of 150 mm and a focus length of 108 mm.The di-ameter of solar spot applied here(1.5—20.0 mm)was obtained by adjusting the position of the sample within the focus length.It was found that,as the diameter of solar spot decreases,the internal conductive heat loss increases,and the critical radiant heat flux required for ignition increases.Afterwards,a 2-D numerical model was established based on the open-source code Gpyro to reproduce the experimental phenomena and validate the experimental results.This work quantifies the fire risk of concentrated solar spots and provides some guidance for future fire protection strategies.

关 键 词：阴燃 临界热通量 光斑 加热面积 火灾 

分 类 号：TK11[动力工程及工程热物理—热能工程]