【摘要】 基于广义Hele—Shaw流动模型,通过引入合理的简化和假设,建立了实现气体辅助注射成形充模流动模拟的数学方程、气体穿透过程的边界条件、CAD/CAE建模关键技术以及系统程序设计方法等。该研究对气体的穿透过程、压力场分布、小同时刻熔体/气体边界的移动状态以及在模壁上形成表层聚合物熔体壁厚的过程进行_了气体辅助注射成形充模流动的实例数值模拟研究。结果表明:增大气体注射压力,在其气体穿透方向所形成的表层熔体厚度比值也增人,降低熔体注射温度和非牛顿指数会增大气体穿透的壁厚值,其值接近试验测定的数值范围,也比较符合实际的气辅注射成形工艺结果。更多还原

【Abstract】 Based on the generalized Hele-Shaw, the mathematic model of cavity filling in gas-assisted injection molding(GAIM), boundary condition of gas penetration, key technology of CAD/CAE model, and the system programming method are set up by providing reasonably accurate assumptions. This numerical simulation on gas penetration, pressure field, displacement process of melt-gas boundary in different time, and skin melt forming on the cavity wall is developed for GAIM parts. Research results show that increasing gas injection pressure or decreasing melt temperature and Non-Newtonian index makes the thickness ratio increase. These results are close to experimental values by other investigators and consistent with actual GAIM process.更多还原