摘要
本文对分散型固液两相混合物层流管流中非均匀剪切力场导致的微对流现象以及由此引起的导热系数增强效应作了机理和影响因素分析,认为除速度分布、颗粒浓度和粒径以外,还存在颗粒形状、粒径分布,壁面热流方向、颗粒表面性质及其与载流介质间的相容性等多个影响因素.模拟计算表明,由微对流导致的对流换热强化与流体在管壁面上的表观导热系数强化具有相同的数量。
The physical mechanism and its dependence factors of micro-convection by uneven shear stress for dispersed solid-liquid mixture in the laminar internal flow, as well as effect of the conductivity enhancement are analyzed in this paper. It is considered that there are many influence factors such as shape of particle, diameters distribution of particles, heat flux direction in the pipe surface, superficial characteristics of particles and the consistency between particle and carrier fluid, besides velocity profile, concentration and diameter of particles. Simulation computation indicates that enhancement by micro-convection has identical magnitude as that by apparent conductivity of fluid in the pipe wall.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2005年第4期656-658,共3页
Journal of Engineering Thermophysics
基金
国家自然科学基金资助项目(No.50276044)
关键词
固液两相流
微对流
剪切力
表观导热系数
对流换热强化
solid-liquid flow
micro-convection
shear stress
apparent conductivity
convection enhancement
