In industry, synthetic fibre reinforcements are popular due to their cost-effectiveness and lightweight nature. However, the non-reusability and non-degradability have raised environmental concerns and prompted scientists to explore more environmentally friendly alternatives. Natural fibres are being investigated as potential replacements to address these issues and promote sustainability. This study investigated the effect of fibre loading and orientation on the heat conductivity of polymer resins using a finite element-based numerical model developed in our previous research. The numerical analysis was conducted in ANSYS® modelling and simulation using glass and sisal fibres in combination with three distinct matrix materials (epoxy, polyester, and vinyl ester). Different orientations (parallel, perpendicular, 45°, and normal) and volume of fibre fractions (20–35%) were used for the analysis. The properties of the materials were incorporated into the ANSYS Engineering database, and the composite model was divided into five segments to analyse the heat transfer. The thermal boundary condition was implemented by keeping one side of the cylinder at 120°C. The results showed that the thermal conductivity of the composites decreased as the volume fraction of natural fibres increased. Epoxy-based composites exhibited better insulation performance than polyester and vinyl ester-based composites. This study demonstrated the potential of using natural fibres to improve the thermal insulation properties of composites.

中文翻译：

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取向和纤维体积对增强聚合物复合材料隔热性能影响的理论研究

在工业中，合成纤维增强材料因其成本效益和轻质特性而广受欢迎。然而，不可重复使用性和不可降解性引起了环境问题，并促使科学家探索更环保的替代品。人们正在研究天然纤维作为解决这些问题并促进可持续发展的潜在替代品。本研究使用我们之前研究中开发的基于有限元的数值模型，研究了纤维负载和取向对聚合物树脂导热率的影响。数值分析是在 ANSYS® 建模和仿真中使用玻璃和剑麻纤维与三种不同的基体材料（环氧树脂、聚酯和乙烯基酯）相结合进行的。使用不同方向（平行、垂直、45° 和法向）和纤维分数体积 (20–35%) 进行分析。材料的特性被纳入ANSYS Engineering数据库中，并将复合材料模型分为五段来分析传热。通过将圆柱体的一侧保持在 120°C 来实现热边界条件。结果表明，随着天然纤维体积分数的增加，复合材料的导热系数降低。环氧树脂基复合材料表现出比聚酯和乙烯基酯基复合材料更好的绝缘性能。这项研究证明了使用天然纤维提高复合材料隔热性能的潜力。