ANALYTICAL MODEL FOR PREDICTION OF EFFECTIVE THERMAL CONDUCTIVITY OF A THREE-PHASE SYSTEM: NANOPARTICLE AS THE THIRD PHASE

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.