消失模发泡珠粒射料充填过程模拟  

SIMULATION ON FILLING PROCESS OF EXPANDED BEADS IN LOST FOAM MOLDING BOX

作　　者：陈尧剑[1] 黄天佑[1] 康进武[1] 

机构地区：[1]清华大学机械工程系,北京100084

出　　处：《机械工程学报》2006年第B05期179-182,共4页Journal of Mechanical Engineering

摘　　要：针对消失模铸造模样制造过程中的发泡珠粒射料充填问题,建立数学模型描述珠粒射料充填过程中的气固两相流动过程并进行了数值模拟,采用双流体模型描述气体相和颗粒相,SIMPLE方法求解气固两相的连续方程和动量方程。为验证模拟结果,采用自行设计的模具进行珠粒射料充填,并用数码摄像机记录了整个射料过程。数值模拟和试验结果显示:在射料充填前期,模具底部空气流动速度快,携带能力强,到达模具底部的珠粒都被带到顶部堆积。珠粒充填超过2／3以后,珠粒才开始在底部堆积,最后形成一个椭圆形漩涡并逐步消失。数值模拟和试验结果符合较好。A mathematical model based on the two-phase theory is built to evaluate the main factors influencing the filling process of the expanded beads in the lost foam casting. In the model, Eulerian-Eulerian method is used to describe the gas and particle phases and the continuity. Momentum equations are solved by SIMPLE algorithm to obtain the flow, phases concentration distribution. To benchmark the numerical results, experiment on the filling process of expanded beads is carried out and the experimental result is recorded with a camcorder. In the beginning of the injection process, the large air velocity carries the beads from the mold bottom to the top where they accumulate. The beads begin to deposit at the bottom as 2/3 of the whole injection process has progressed and at final stage an elliptical vortex forms. The vortex becomes smaller and smaller and disappears as the filling process finishes. The preliminary results show that the calculation is in agreement with the experiment results.

关 键 词：消失模 发泡珠粒 射料充填过程 两相流 数值模拟 

分 类 号：TG24[金属学及工艺—铸造]