{"title":"用等效椭圆法研究湍流扩散火灾的烟炱特性","authors":"Yubo Bi, Yanghui Hu, Shouxiang Lu, Haiyong Cong, Wei Gao, Mingshu Bi","doi":"10.1002/fam.3130","DOIUrl":null,"url":null,"abstract":"<p>This paper investigates the soot sheet characteristics of buoyant turbulent fires using laser-induced incandescence technique. Experiments are carried out for four fires using propane and nitrogen hybrid gases as fuel with propane fractions of 1.0–0.4. An equivalent ellipse method in previous literature was employed to evaluate soot sheet characteristics. The results show that soot sheet mainly exists in two kinds of morphology: one is small piece and the other is narrow and long piece. Both the probability density functions of the length and width of the equivalent ellipse and soot volume fraction of soot sheet are strongly dependent on height. In addition, the effect of propane fraction on the probability density functions is always opposite in the lower and middle part of the fires, while no obvious effect can be found in the upper part of the fires. Soot sheet number is found to increase with height except when propane fraction is 0.4. The total soot sheet number increases linearly with height within the scope of this paper.</p>","PeriodicalId":12186,"journal":{"name":"Fire and Materials","volume":null,"pages":null},"PeriodicalIF":2.0000,"publicationDate":"2023-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Soot sheet characteristics of turbulent diffusion fire using equivalent ellipse method\",\"authors\":\"Yubo Bi, Yanghui Hu, Shouxiang Lu, Haiyong Cong, Wei Gao, Mingshu Bi\",\"doi\":\"10.1002/fam.3130\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>This paper investigates the soot sheet characteristics of buoyant turbulent fires using laser-induced incandescence technique. Experiments are carried out for four fires using propane and nitrogen hybrid gases as fuel with propane fractions of 1.0–0.4. An equivalent ellipse method in previous literature was employed to evaluate soot sheet characteristics. The results show that soot sheet mainly exists in two kinds of morphology: one is small piece and the other is narrow and long piece. Both the probability density functions of the length and width of the equivalent ellipse and soot volume fraction of soot sheet are strongly dependent on height. In addition, the effect of propane fraction on the probability density functions is always opposite in the lower and middle part of the fires, while no obvious effect can be found in the upper part of the fires. Soot sheet number is found to increase with height except when propane fraction is 0.4. The total soot sheet number increases linearly with height within the scope of this paper.</p>\",\"PeriodicalId\":12186,\"journal\":{\"name\":\"Fire and Materials\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":2.0000,\"publicationDate\":\"2023-02-09\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Fire and Materials\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1002/fam.3130\",\"RegionNum\":4,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"MATERIALS SCIENCE, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Fire and Materials","FirstCategoryId":"88","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/fam.3130","RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
Soot sheet characteristics of turbulent diffusion fire using equivalent ellipse method
This paper investigates the soot sheet characteristics of buoyant turbulent fires using laser-induced incandescence technique. Experiments are carried out for four fires using propane and nitrogen hybrid gases as fuel with propane fractions of 1.0–0.4. An equivalent ellipse method in previous literature was employed to evaluate soot sheet characteristics. The results show that soot sheet mainly exists in two kinds of morphology: one is small piece and the other is narrow and long piece. Both the probability density functions of the length and width of the equivalent ellipse and soot volume fraction of soot sheet are strongly dependent on height. In addition, the effect of propane fraction on the probability density functions is always opposite in the lower and middle part of the fires, while no obvious effect can be found in the upper part of the fires. Soot sheet number is found to increase with height except when propane fraction is 0.4. The total soot sheet number increases linearly with height within the scope of this paper.
期刊介绍:
Fire and Materials is an international journal for scientific and technological communications directed at the fire properties of materials and the products into which they are made. This covers all aspects of the polymer field and the end uses where polymers find application; the important developments in the fields of natural products - wood and cellulosics; non-polymeric materials - metals and ceramics; as well as the chemistry and industrial applications of fire retardant chemicals.
Contributions will be particularly welcomed on heat release; properties of combustion products - smoke opacity, toxicity and corrosivity; modelling and testing.