注塑成型过程的多尺度光滑粒子流体动力学模拟  

Multiscale smoothed particle hydrodynamic simulation of injection molding

作　　者：许晓阳 田凌云 XU Xiaoyang;TIAN Lingyun(College of Safety Science and Engineering,Xi'an University of Science and Technology,Xi'an 710054,China;College of Computer Science and Technology,Xi'an University of Science and Technology,Xi'an 710054,China)

机构地区：[1]西安科技大学安全科学与工程学院,西安710054 [2]西安科技大学计算机科学与技术学院,西安710054

出　　处：《清华大学学报（自然科学版）》2024年第8期1401-1413,共13页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金面上项目(12071367);陕西省“特支计划”青年拔尖人才资助项目(289890259)。

摘　　要：注塑成型是聚合物成型加工领域中的一类重要方法。传统的注塑成型数值模拟大多局限于宏观模型求解,然而塑料制品的性能与其微观分子结构密切相关,建立注塑成型模拟的微宏观耦合计算方法具有重要的学术和应用价值。该文基于珠-簧链模型,提出多尺度光滑粒子流体动力学(SPH)方法,对黏弹性注塑成型过程进行了数值模拟研究。该方法在宏观尺度上采用SPH方法求解质量和动量守恒方程,在微观尺度上采用Brown构型场方法求解弹性应力。通过将黏弹性Couette流的模拟结果与解析解对比,验证了该多尺度方法的有效性。模拟了C形腔和N形腔注塑成型问题,展示了成型过程中的微宏观物理信息变化情况,研究了不同流变参数对成型过程的影响。研究结果表明:提出的多尺度SPH方法可稳定、准确地模拟注塑成型过程,并能计算得到传统宏观方法无法获得的一些微观分子信息。[Objective]Injection molding is an important method in polymer molding processing.Numerical simulations have proven effective in studying viscoelastic injection molding problems.Traditional numerical simulations of injection molding typically rely on macroscale models.However,the performance of plastics is closely related to their micromolecular structure.Understanding the evolution of the micromolecular structure is essential for improving product quality.Therefore,the simulation study of coupling micro-and macroscales has important academic and practical value.[Methods]In this study,a multiscale smoothed particle hydrodynamic(SPH)method based on the bead-spring chain model is used to simulate viscoelastic injection molding.At the macroscale,the conservation equations of mass and momentum are solved using the SPH method,whereas at the microscale,the elastic stress is described using the Brownian configuration field method.The viscoelastic Couette flow is simulated using three types of bead-spring chain models.The effectiveness of the multiscale SPH method is verified by comparing simulation results with analytical solutions of the viscoelastic Couette flow of the Hookean dumbbell model and by comparing the numerical solutions of the viscoelastic Couette flow of the finitely extensible nonlinear elastic dumbbell model with the literature results.The bead-spring dumbbell model is extended to a bead-spring chain model,and the Couette flow is simulated.The influence of different numbers of beads on the viscoelastic flow is analyzed,and an appropriate number of beads is selected for numerical simulations.In addition,the multiscale SPH method is extended to simulate injection molding in C-shaped and N-shaped cavities.Micro-and macro-parameters in injection molding are investigated,including the first normal stress difference,molecular stretch,and mean conformation thickness.The convergence of the multiscale SPH method is evaluated by changing the total number of SPH fluid particles Nf at the macroscale and the total n

关 键 词：光滑粒子流体动力学(SPH) 珠-簧链模型 注塑成型 黏弹性流体 多尺度建模 

分 类 号：TQ320.66[化学工程—合成树脂塑料工业] O368[理学—流体力学]