煤炭粉尘颗粒起动风速影响因素及数学模型  

Influence factors and mathematical model of coal dust particles threshold velocity

作　　者：韩桂波[1] 詹水芬[2] 张晓春[2] 马春[3] 

机构地区：[1]铁道第三勘察设计院集团有限公司,天津300142 [2]交通部天津水运工程科学研究所水路交通环境保护技术实验室,天津300456 [3]南开大学环境科学与工程学院,天津300071

出　　处：《煤炭学报》2009年第10期1359-1363,共5页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(50805115);交通部科技项目(2007-353-312-030)

摘　　要：通过风洞模拟实验及对影响煤炭颗粒起动过程主要因子的分析,推演了水分对粉尘起动的影响机理,并建立煤炭粉尘颗粒起动风速数学模型.结果表明,煤炭粉尘颗粒的起动风速不仅与粒径有关,也与水分有关.在水分较低条件下,粉尘颗粒的起动风速与粒径相关,符合Bag-nold等的经典模型;在水分含量较高时,Bagnold等的经典模型不再适用于描述粉尘的起动风速规律,受水分的影响较大.水分对煤炭粉尘起动风速的影响主要有亲水效应和凝聚效应2个方面.凝聚效应的发生存在粒径阈值和含水率阈值2个临界.对煤炭粉尘颗粒,粒径阈值为180μm,含水率阈值与粒径呈线性关系.根据煤炭粉尘颗粒的起动特征,基于经典模型和水分影响理论分析得出煤炭粉尘颗粒的起动风速的新模型.The mechanism that moisture effecting on threshold velocity of coal dust was derived, and a model that characterized the threshold velocity of coal dust particles was established, based on a wind tunnel simulation experiments. The results show that the threshold velocity of coal dust is not only concerned with the size of particles, but also moisture. In the low moisture conditions, the threshold velocity depends on particle size as Bagnold＇ s model; but in the high moisture content, the threshold velocity is moisture-related, but not suitable for Bagnold＇ s model. Two main effects of moisture are hydrophilic interaction and agglutinate interaction. When particles size is smaller than size threshold and moisture content is higher than moisture threshold, the agglutinate interaction will occur. For coal, size threshold is 180 μm, and moisture threshold is linear relationship with particle size. For describing the characteristics of the coal dust threshold velocity better, a new model was built.

关 键 词：颗粒物 起动风速 亲水作用 凝聚作用 

分 类 号：TQ534.9[化学工程—煤化学工程]