摘要
进行了半环对撞流干燥流动特性的实验与理论研究。实验测定了物料颗粒在环内的运动速度与停留时间沿运动方向的变化，系统压降随载带率的变化等。计算并讨论了不同工况下物料颗粒在环内的运动速度与停留时间的变化规律、颗粒的最大穿透深度与穿透时间及各种因素对流动特性的影响。研究结果表明，对撞区内气固相对速度较大，是强化半环对撞流干燥的有利场所；适当增加环的直径是强化半环对撞流干燥的有效方法；实际干燥过程中存在一合理的气流速度，使其相应的干燥速率最大，干燥的能耗与费用最低。
Experimental and theoretical studies on the flow characteristics of semi circular impinging stream drying were made. The variations of the particle’s velocity,the residence time along particle’s track,and the system pressure drop versus mass flow rates were determined by experiment. The particle dynamic model was developed. Under various conditions, the particle’s velocity, residence time, maximum penetration depth and the maximum penetration time, as well as the effects of various factors on fluid dynamic characteristics were calculated and discussed. The calculatied results agree well with the experimental data. The results indicate that impinging region is the favorable field of enhancement semi circular impinging stream drying, increasing circular diameter properly is the efficient way of enhancement semi circular impinging stream drying,and reasonable gas velocity should be used to reduce the energy consumption and the operating cost.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
1998年第4期67-72,共6页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金
中国科学院"九五"基础性研究重大项目
关键词
半环对撞流
流动特性
颗粒动力学
semi circular impinging stream, flow characteristics, particle dynamics
