Effective thermal conductivity in nanofluids of nonspherical particles with interfacial thermal resistance: Differential effective medium theory

Abstract

By taking into account the interfacial thermal resistance across the solid particles and the host liquids, we present differential effective medium theory to estimate the effective thermal conductivity in nanofluids of nonspherical solid particles. It is found that high enhancement of effective thermal conductivity can be achieved when the nanoparticles’ shape is deviated much from the spherical one. On the other hand, increasing the interfacial thermal resistance results in an appreciable degradation in the thermal conductivity enhancement. To one’s interest, our theoretical results are in good agreement with recent experimental data on nanofluids. In particular, our theoretical predictions successfully show the nonlinear dependence of effective thermal conductivity on the volume fractions of nanotubes.