颗粒物质从稀疏流到密集流转变的普适规律  

Global property of the dilute-to-dense transition of granular flows in a 2D channel

作　　者：厚美瑛[1] 陈唯[1] 张彤[1] 陆坤权[1] 陈志强[2] 

机构地区：[1]中国科学院物理研究所,北京100080 [2]中央研究院物理研究所

出　　处：《物理》2004年第7期473-476,共4页Physics

基　　金：国家自然科学基金 (批准号 :A0 40 2 -10 2 740 98)资助项目

摘　　要：二维颗粒流实验研究发现 ,当初始稀疏颗粒流量固定 ,出口的尺寸减小到一临界值 ,或固定出口的尺寸 ,颗粒流量增大到一临界值时 ,都会发生流量的突然减小 ,从稀疏流转变为密集流 .得到了临界流量与出口尺寸、颗粒尺寸及通道宽度之间的普适标度关系 ,揭示了“瓶颈效应”Dilute\|to\|dense transition of granular flow is observed in a two\|dimensional channel with confined exit. It is found that for a fixed width of the channel and exit there is a maximum outflow rate. This is reached when the inflow reaches a critical rate Q c as the outflow changes from dilute to dense, and the flow rate drops abruptly. We find that a rescaled critical flow rate is a function of a scaling variable λ only. The form of λ suggests that the dilute-to-dense transition is a global property of the flow.

关 键 词：颗粒流 相变 动力学性质 稀疏流 密集流 流变学 

分 类 号：O552[理学—热学与物质分子运动论]