旋转盘离心雾化熔滴飞行动力学与凝固进程  

Droplet dynamic and solidification progress during rotating disk centrifugal atomization

作　　者：李会平[1] P.Tsakiropoulos 

机构地区：[1]华东理工大学无机材料系,上海200237 [2]School of Mechanical and Materials Engineering,University of Surrey, Guildford Surrey GU2 7XH,UK

出　　处：《中国有色金属学报》2006年第5期793-799,共7页The Chinese Journal of Nonferrous Metals

摘　　要：建立了旋转盘离心雾化熔滴飞行与凝固进程的一个数学模型,并用Runge-Kutta方法进行数值求解,模拟镍金属熔滴飞行与凝固的基本情况,探讨过程和材料参数的影响。结果表明:在旋转盘离心雾化中熔滴经历了一个大的过冷,其过冷度约为0.2Tm;在整个飞行期间,熔滴的冷却速率并不是常数,在熔点附近冷却速率约为5×104K/s;角速度越大,冷却速率越大,熔滴开始和完成凝固所需时间越短,雾化室可小些;熔滴过热温度对熔滴过冷度和冷却速率影响不明显,但完成凝固所飞行的距离增大,从雾化室设计角度,不宜采用大的过热温度。A mathematical model of droplet dynamic and solidification progress during rotating disk centrifugal atomization was developed and numerically solved by Runge-Kutta＇s method. The flight and solidification of a nickel droplet was simulated. The effect of process and materials parameters was studied. The results show that the droplet experiences a large undercooling of about 0.2Tm and the cooling rate is not constant during the flight, about 5 × 10^4 K/s at the melting point. With increasing disk speed the cooling rate increases, and this leads an early start and completion of solidification. A small atomizing chamber can be used. The droplet superheat has a weak effect on nucleation temperature and cooling rate, but the flight distance at f= 1 increases. Therefore, a high droplet superheat is not suitable for the design of atomizing chamber.

关 键 词：离心雾化 旋转盘 飞行与凝固 数学模型 

分 类 号：TF123.23[冶金工程—粉末冶金]