共挤出机头中的聚合物熔体流动分析

采用Hele-Shaw模型对共挤出机头流道内的聚合物熔体流动进行了数值模拟分析，计算得到了衣架型机头出口处各层料流分界面的位置，并讨论了物料特性、进口处流率比对机头出口处分界面位置的影响。     

基于CAE技术优化ABS弯头管件的浇口位置

利用CAE软件Moldflow,对ABS弯头管件不同浇口位置的充模流动过程进行了模拟分析,综合考虑浇口位置与制品气泡数目和分布状况、制品熔接痕数目和分布状况、流动前沿温度变化情况的关系以及模具结构,建议采用浇口位置2。     

热流道注射模中充模力的计算

就热流道注射模具，根据塑件形状不同，分析了熔体在等温流动和非等温流动时，流经不同位置时的压力损失。推导出了计算充模压力的数学模型。     

环形管内涡旋流动特性及传热机理研究

对不同初始旋流强度的空气介质在环形管内涡旋流动特性及传热机理的试验研究，得到了表示涡流喷嘴位置及方向的几何参数与传热系数及压力降的关系。实验表明，涡旋流动有明显的强化传热作用。     

MoldFlow在注塑模具浇口优化设计中的应用

为了减少试模次数，运用Moldnow软件进行浇口优化设计的流程图，并对手机外壳进行了流动模拟分析，获得了满意合理的浇口数量和位置。     

塑料注射充模过程的动态磁化测量及表征

为了研究塑料熔体在模腔内的流动行为，设计制造了浇口动态磁化装置，通过磁化试验，测量中心浇口圆盘模腔内的熔体在各个时刻的流动位置和充模时间，可以直观地分析塑料熔体在模腔中的流动状态。     

基于Moldflow软件的开关盒上盖浇口优化设计

利用Moldflow软件,对开关盒上盖的注塑过程中的流动情况进行了模拟.通过设定不同的浇口位置和数量,分析了填充时间、流动前沿温度、气穴位置、熔接痕数量和位置的变化情况,从而优化设计方案,最终获得合适的浇口位置,为模具设计提供了依据.     

基于填充模式优化的注塑模具浇口位置的优化设计

分析了平板类零件的流动规律，提出了基于流动模式优化的注射浇口位置优化选取的原则；并以等厚平板制件单浇口注射成型工艺为例，建立了针对制件不同几何特征要求的最佳浇口位置的描述方式及相应的数学模型，并给出了优化算法；研究并提出了在CAD系统中，任意形状零件边界特征点的提取方法，为优化算法的实施提供了基础。     

塑料注塑成型浇口位置优化

塑料注塑成型可以制作大量具有高精度和复杂型腔形状的制件,其中注塑模浇口位置的设定决定了聚合物流动方向和流动平衡性,产品质量可以通过浇口位置的优化得到显著提高.通过对导致制品翘曲和影响材料性能的主要因素进行定量分析构造了浇口位置优化问题,结合遗传算法和数值模拟技术对优化问题求解,得到最优浇口位置设计.算例证明该方法不仅适用于单浇口位置优化,也适用于多浇口位置优化.     

吸气式浮选旋流器内部流场理论分析

利用Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程对吸气式浮选旋流器内部流场的速度分布及压力分布作了系统的理论分析研究．并对该方程进行了简化，合理地确定边界条件，根据流动特性对其加以修正，使其客观地反映了旋流器内部流场的真实流动状态，从而得出旋流器的分界面位置，旋流器中心存在空气柱，其大小取决于溢流管的直径、入料速度及入料压力．这一结论对旋流器内物料的分级性能具有决定性作用．     

Experimental study on filling imbalance of plastic parts with microcylinders

To examine the microscale filling imbalance in the present work, an eight-cavity injecting mold with microcylindrical-hole arrays fabricated by micro-electrical discharge machining milling technology was developed. Polypropylene (PP) was used to carry out single factor filling flow experiments with vacuuming the mold cavities. The filling height difference of micro cylindrical hole at the same position between cavity I and cavity II, which was the index of filling imbalance and the effect of mold temperature and injection rate on the filling imbalance of microholes with diameters of 200 μm and 300 μm was investigated. The results revealed that the maximum height difference reached 101 μm with low process parameters, and the filling imbalance was obvious. With the increase in mold temperature and injection rate, the filling imbalance was weakened. In addition, the impact of the scale effect on filling imbalance was checked. The filling imbalance of micro holes in 200 μm was greater than that in 300 μm using identical process parameters. With the increase in mold temperature and injection rate, the filling height difference of the two kinds of micro holes decreased. POLYM. ENG. SCI., 60:22–31, 2020. © 2019 Society of Plastics Engineers     

螺杆轴向振动对圆盘模腔充模功率的影响

探讨注射成型过程中振动力场对圆盘模腔充模过程的影响，建立起数学模型，推导出相应的功率表达式，分析了振动频率和振幅对圆盘模腔充模功率的影响，而且通过实验验证了振动力场的引入使得圆盘模腔充模功率降低。     

双组分注射成型件体积收缩的数值模拟研究

以ABS为第一次成型的内嵌件材料,PP为第二次成型的外嵌件材料,通过对双组分注射成型的数值模拟,系统研究了熔体注射温度、模具温度、注射时间、保压时间和冷却时间等工艺参数对其平均体积收缩率的影响规律,并基于流变学理论,揭示了其影响机理。结果表明,随着熔体注射温度和模具温度的升高,双组分注射成型制品的体积收缩增加,而随着注射时间、保压时间和冷却时间的增加,其平均体积收缩率减小。     

Moldflow软件在无绳电话机底盖模具设计中的应用

运用Moldflow软件,对无绳电话机底盖注塑成型过程的填充、保压、冷却进行模拟,详细分析了Moldflow软件在注塑模具优化设计中的应用。结果表明,Moldflow分析与实际生产中的成型工艺非常相近,其分析结果对塑料模具优化设计具有良好的指导作用。     

基于SPH方法的微注射成型数值模拟

基于无网格方法和黏性本构方程,开展微注射成型数值模拟的研究。采用光滑粒子流体动力学的粒子近似法离散N-S 控制方程组,求解速度场、压力场、温度场等物理场的变化规律。以应用于生物医学领域带有细微针头的聚合物微针为例,进行充型过程的数值模拟,模拟结果与实验结果基本一致。     

Experimental Results of Low Thermal Inertia Molding. I. Length of Filling

In injection molding, complete mold cavity filling is a design goal that has to be met 100% every time. Mold cavity filling is a complicated process which depends on many variables such as mold cavity surface temperature, injection pressure, injection speed, melt temperature, flow index of material being molded, etc. The aim of experimental investigation of the low thermal inertia molding (LTIM) [1] process is to demonstrate the feasibility of molding completely filled, thin parts at low injection pressure and injection speed without sacrificing part quality. The evaluation of the new molding concept consists of comparison of a conventionally molded thin rectangular part with an identical part molded by the LTIM process. The length of filling in the conventional cavity and in the LTIM cavity are compared at different injection pressures and injection speeds. The mold design, experimental procedure, and results of the molding are discussed in the following sections.     

微细发泡注塑成型工艺与微泡尺寸的关系

以数值模拟作为实验手段,工艺参数对微泡长大的影响的判断则采用田口实验方法来进行;结果得出各工艺参数对微泡尺寸的影响次序由大到小为：熔体温度、初始填充量、注射时间、模具温度。在此基础上,进一步研究了各个工艺参数对微泡长大的影响,得出适当降低熔体温度和提高初始填充量可以优化微细发泡注塑制品的微泡尺寸;而注塑时间和模具温度对微泡尺寸的影响不大。     

Numerical Simulation for Injection Molding with a Rapidly Heated Mold,Part I: Flow Simulation for Thin Wall Parts

The rapid thermal response (RTR) injection molding is a novel process developed to raise the mold surface temperature rapidly to the polymer melt temperature prior to the injection stage and then cool rapidly. The resulting filling process is achieved inside a hot mold cavity by prohibiting formation of frozen layer so as to enable thin wall injection molding without filling difficulty. The present work covers flow simulation of thin wall injection molding using the RTR molding process. Both 2.5-D shell analysis and 3-D solid analysis were performed, and the simulation results were compared with the prior experimental results. Coupled analysis with transient heat transfer simulation was also studied to realize more reliable thin-wall-flow estimation for the RTR molding process. The proposed coupled simulation approach based on solid elements provides reliable flow estimation by accounting for the effects of the unique thermal boundary conditions of the RTR mold.     

Space-time distribution in filling a mold

The residence time of a fluid particle in mold filling is total time spent in the mold. Displaying curves of constant residence time in the mold gives the space-time distribution during the filling process. A simple method to calculate space-time distributions is presented. Applications to mold filling in reaction injection molding (RIM) are illustrated.     

基于Moldflow的电子镇流器底壳注射成型分析

利用Moldflow软件对电子镇流器底壳注射成型过程中最佳浇口位置和流动情况进行分析,确定了最佳浇口位置。通过对填充时间、气穴、熔接痕、锁模力曲线和流动前沿温度等数值模拟,预测塑件可能出现的缺陷,显示了Moldflow技术在模具开发过程中对于优化塑料注射模设计和优化注射工艺参数等方面所起到的显著作用。