The thermal design of various engineering applications plays a prominent role in deciding the overall efficiency of the system. Nowadays, nanofluids have attracted the interest of researchers due to their excellent thermophysical properties. There were several researches emphasising the importance of two-phase materials and nanofluids in the effective thermal design, but none have attempted to integrate both for analyzing their combined potential thermal benefits. This research paper is aimed at formulation of the general analytical expression using the unit cell approach for the evaluation of effective thermal conductivity (ETC) of two-phase system which is comprised of solid and liquid with nanoparticles as a third phase dispersed in the liquid phase (so called nanofluids). The expressions are evaluated for different samples (packed beds and foams dispersed in nanofluid) and compared with the experimental results of conventional two-phase system. The combined effects of influencing parameters on two-phase materials with the static and dynamic mechanisms of nanofluids have been studied and validated with the standard models. The present model is better suit for predicting ETC of two-phase system in different combinations with nanofluids.

中文翻译：

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三相系统有效热导率的解析模型：以纳米粒子为第三相

各种工程应用的热设计在决定系统的整体效率方面发挥着重要作用。如今，纳米流体因其出色的热物理性质而吸引了研究人员的兴趣。有几项研究强调了两相材料和纳米流体在有效热设计中的重要性，但没有人试图将两者结合起来以分析其组合的潜在热效益。本研究论文旨在使用单位晶格方法制定通用分析表达式，以评估两相体系的有效导热系数（ETC），该体系由固体和液体组成，纳米颗粒作为第三相分散在液相中（所谓的纳米流体）。对不同样品（填充床和泡沫分散在纳米流体中）的表达式进行了评估，并与常规两相系统的实验结果进行了比较。通过标准模型研究和验证了影响参数对两相材料的影响以及纳米流体的静态和动态机理。该模型更适合预测与纳米流体不同组合的两相系统的ETC。