Scholarlink

<p>Although fused filament fabrication is one of the most accessible additive manufacturing processes, little is known about the thermal-fluid flow during the extrusion of elastic materials due to the presence of elastic stresses. In this study, a conjugate heat transfer model is employed to extend previous numerical investigations of molten polymer extrusion processes within the nozzle, while considering the effects of viscoelasticity. We find the existence of a critical value of the polymer elasticity, at which the heat transfer efficiency and outlet temperature reach their maximum, with the melting length being minimized. Meanwhile, the enhancement of elasticity leads to a gradual decline in the polymer's pressure drop, culminating in a stable equilibrium condition. Under three different inlet velocities, the pressure drop decreased to 72%, 69%, and 64% of its original value, respectively. The pressure drop showed factors of 3.7, 5.1, and 6.9 as the inlet velocity rose from 1 to 7&#xa0;mm·s−1, with 5&#xa0;mm·s−1 identified as the limiting velocity for complete polymer melting. The heat source location significantly influences the wall temperature gradient distribution. Positioning thermocouples away from the heating zone provides more accurate feedback signals for precise heating control. The research findings can provide theoretical guidance for improving 3D printers.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Modeling and analysis of non-isothermal viscoelastic polymer flow in fused filament fabrication

  • 期刊论文

  • 发表日期：

    2025年10月8日

查看全文
  • Qinlei Luan,
  • Haifeng Zhang,
  • Wennuo Gong,
  • Wenjun Yuan,
  • Fei Chen,
  • Wentao Yan

摘要

Although fused filament fabrication is one of the most accessible additive manufacturing processes, little is known about the thermal-fluid flow during the extrusion of elastic materials due to the presence of elastic stresses. In this study, a conjugate heat transfer model is employed to extend previous numerical investigations of molten polymer extrusion processes within the nozzle, while considering the effects of viscoelasticity. We find the existence of a critical value of the polymer elasticity, at which the heat transfer efficiency and outlet temperature reach their maximum, with the melting length being minimized. Meanwhile, the enhancement of elasticity leads to a gradual decline in the polymer's pressure drop, culminating in a stable equilibrium condition. Under three different inlet velocities, the pressure drop decreased to 72%, 69%, and 64% of its original value, respectively. The pressure drop showed factors of 3.7, 5.1, and 6.9 as the inlet velocity rose from 1 to 7 mm·s−1, with 5 mm·s−1 identified as the limiting velocity for complete polymer melting. The heat source location significantly influences the wall temperature gradient distribution. Positioning thermocouples away from the heating zone provides more accurate feedback signals for precise heating control. The research findings can provide theoretical guidance for improving 3D printers.