Mercado-Colmenero Jorge Manuel, Torres-Alba Abelardo, Catalan-Requena Javier, Martin-Doñate Cristina
Department of Engineering Graphics Design and Projects, University of Jaen, 23071 Jaen, Spain.
Polymers (Basel). 2021 Aug 16;13(16):2744. doi: 10.3390/polym13162744.
The paper presents a new design of conformal cooling channels, for application in collimator-type optical plastic parts. The conformal channels that are presented exceed the thermal and dynamic performance of traditional and standard conformal channels, since they implement new sections of complex topology, capable of meeting the high geometric and functional specifications of the optical part, as well as the technological requirements of the additive manufacturing of the mold cavities. In order to evaluate the improvement and efficiency of the thermal performance of the solution presented, a transient numerical analysis of the cooling phase has been carried out, comparing the traditional cooling with the new geometry that is proposed. The evolution of the temperature profile versus the thickness of the part in the collimating core with greater thickness and temperature, has been evaluated in a transient mode. The analysis of the thermal profiles, the calculation of the integral mean ejection temperature at each time of the transient analysis, and the use of the Fourier formula, show great improvement in the cycle time in comparison with the traditional cooling. The application of the new conformal design reduces the manufacturing cycle time of the collimator part by 10 s, with this value being 13% of the total manufacturing cycle of the plastic part. As a further improvement, the use of the new cooling system reduces the amount of thickness in the collimator core, which is above the ejection temperature of the plastic material. The improvement in the thermal performance of the design of the parametric cooling channels that are presented not only has a significant reduction in the cycle time, but also improves the uniformity in the temperature map of the collimating part surface, the displacement field, and the stresses that are associated with the temperature gradient on the surface of the optical part.
本文提出了一种用于准直器型光学塑料零件的新型随形冷却通道设计。所提出的随形通道超越了传统和标准随形通道的热性能和动态性能，因为它们采用了复杂拓扑的新截面，能够满足光学零件的高几何和功能规格以及模具型腔增材制造的技术要求。为了评估所提出解决方案的热性能改进和效率，对冷却阶段进行了瞬态数值分析，将传统冷却与所提出的新几何形状进行了比较。以瞬态模式评估了在具有更大厚度和温度的准直芯中温度分布随零件厚度的变化。热分布分析、瞬态分析每次的积分平均顶出温度计算以及傅里叶公式的使用表明，与传统冷却相比，循环时间有了很大改进。新型随形设计的应用使准直器零件的制造周期时间减少了10秒，该值占塑料零件总制造周期的13%。作为进一步的改进，使用新的冷却系统减少了准直芯中高于塑料材料顶出温度的厚度。所提出的参数化冷却通道设计的热性能改进不仅显著减少了循环时间，还改善了准直零件表面温度图的均匀性、位移场以及与光学零件表面温度梯度相关的应力。
