摘要
风速的脉动性对煤炭颗粒起动风速、起尘判别准则和煤堆静态起尘量有着不可忽略的影响.在煤堆起尘量经验公式的基础上,建立风速概率分布模型,推导了考虑风速脉动影响的等效起动风速和等效来流风速,通过定义修正系数来考虑风速脉动的影响,并重新定义了起尘判别准则.结合相关文献风洞试验结果,对不同紊流度和平均风速条件下的修正系数,进行了比较分析.结果表明:在特定紊流度条件下,紊流度对煤炭颗粒起动风速修正系数和来流风速修正系数均有较大的影响.特别是在D类流场,忽略紊流度效应造成的最大误差超过18%.
Threshold wind velocities of coal particles,dusting identification criteria and static dust emissions of coal piles are influenced by fluctuations characteristics of the flow.Based on coal-dust emission empirical formula of the coal piles,and combined with the model of wind velocity probability distributions,the equivalent threshold wind velocities and upstream wind velocities were firstly deduced considering fluctuation effects of the flow,and then the correction factors were redefined to consider it.Besides,referring to literature concerning wind tunnel experiment results,the comparative analysis of correction coefficients under different turbulence and average wind speed conditions was conducted.Given certain turbulence intensities,studies above show that the effects of turbulence intensities on the correction coefficients cannot be ignored,especially in flow field D,where the maximum tolerance can be reached at more than18%.
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2016年第1期189-194,共6页
Journal of China University of Mining & Technology
基金
国家自然科学基金面上项目(51179078)
中央级公益性科研院所基本科研业务费专项资金项目(TKS140215
TKS130204)
关键词
紊流度
等效起动风速
等效来流风速
煤炭颗粒
风洞试验
turbulence intensity
equivalent threshold wind velocity
equivalent upstream wind velocity
coal-dust particle
wind tunnel experiment
