Abstract The tandem extrusion method is quite famous for polymer foaming production in up-scale. In this method, two extruders coupled together for different functionality. The primary extruder used for melting, homogenizing the foaming agent in the melt. The secondary extruder used for reducing the melt temperature to the required foaming temperature limit. In this study, propose newly developed core-hole heat exchanger by replacing secondary extruder as an alternative solution. The heat transfer performance of the core-hole structure investigated in this work. According to heat transfer performance mainly focus on heat transfer rate, temperature distribution, local heat transfer coefficient, Nusselt number, and overall heat transfer coefficient in this work. The experiments were carried out on 180 °C, 190 °C, and 200 °C inlet temperature, whereas the flow rate was 08 to 20 kg/h with 4 unit of the interval. Non-homogeneous temperature distribution resulted in 08 kg/h and 180 °C of the inlet temperature, but overall average temperature approximately similar to surface temperature. Good mix ability and the uniform temperature achieved on 12 and 16 kg/h in all range of temperatures in this study. Whereas, 20 kg/h of mass flow rate reduces the temperature distribution quality of the melt. Because of the higher temperature difference and flow rate, higher heat transfer rate achieved on 200 °C and 20 kg/h. Convective heat transfer coefficient has been increased concerning flow rate and local point temperature difference. In this work, it investigated that 190 °C of inlet temperature gives a higher overall heat transfer coefficient on 16 and 20 kg/h of mass flow rate.

中文翻译：

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新型聚合物发泡工艺芯孔换热器传热性能评价

摘要 串联挤出法在聚合物发泡的大规模生产中颇有名气。在这种方法中，两个挤出机连接在一起以实现不同的功能。初级挤出机用于熔化、均化熔体中的发泡剂。二次挤出机用于将熔体温度降低到所需的发泡温度极限。在本研究中，提出了通过更换二次挤出机作为替代解决方案的新开发的芯孔换热器。在这项工作中研究了芯孔结构的传热性能。根据传热性能，本文主要关注传热速率、温度分布、局部传热系数、努塞尔数和整体传热系数。实验在 180 °C、190 °C 和 200 °C 入口温度下进行，而流速为 08 至 20 kg/h，间隔为 4 个单位。不均匀的温度分布导致入口温度为 08 kg/h 和 180 °C，但总体平均温度与表面温度大致相似。在本研究的所有温度范围内，以 12 和 16 千克/小时的速度实现了良好的混合能力和均匀的温度。而 20 kg/h 的质量流量会降低熔体的温度分布质量。由于更高的温差和流速，在 200 °C 和 20 kg/h 下实现了更高的传热率。关于流速和局部点温差，对流传热系数有所增加。在这项工作中，它研究了 190 °C 的入口温度在 16 和 20 kg/h 的质量流量下提供了更高的整体传热系数。