注塑制品往往具有复杂的几何形状,存在着壁厚的差异。三维流动模型比二维模型能更准确地模拟出熔体充模流动的情况。提出了一种基于全三维模型的注塑成形流动模拟的数学模型和数值实现方法,把速度和压力同次插值的方法成功地应用到三维注塑模拟的计算中,采用三维控制体积追踪塑料熔体的流动前沿,在温度场计算中,全面考虑了对流项在各个方向的影响,使模型的适用范围更广,结果更准确。在此基础上开发了相应的软件,可以计算熔体充模过程中的压力场、速度场和温度场等。实验验证和算例分析说明了三维流动模型的有效性。
Most injection-- molded parts are three-- dimensional, with complex geometrical configurations and thick/thin wall sections. A 3D simulation model, which can generate more complementary and more accurate flow information, will predict the filling process more accurately than a 2D model. Without use of the Hele--Shaw approximation, this paper gave a mathematical model and numerical method based on 3D model, in which an equal--order velocity--pressure interpolation method was employed successfully and a 3D control volume scheme was used to track the flow front. During calculating the temperature field,influences of convection items in three directions were considered in order to get more exact results and to apply to the wider range of parts. The software based on this 3D model can calculate the pressure field, velocity field and temperature field in filling process. Some instances are used to verify that the present formulation is correct and reliable.