Analytical prediction of forced convective heat transfer of ???uids embedded with nanostructured materials (nano???uids)

摘要

Nano???uids are a new class of heat transfer ???uids developed by suspending nanosized solid particles in liquids. Larger thermal conductivity of solid particles compared to the base ???uid such as water, ethylene glycol, engine oil etc. signi???cantly enhances their thermal properties. Several phenomenological models have been proposed to explain the anomalous heat transfer enhancement in nano???uids. This paper presents a systematic literature survey to exploit the characteristics of nano???uids, viz., thermal conductivity, speci???c heat and other thermal properties. An empirical correlation for the thermal conductivity of Al2O3 + water and Cu + water nano???uids, considering the effects of temperature, volume fraction and size of the nanoparticle is developed and presented. A correlation for the evaluation of Nusselt number is also developed and presented and compared in graphical form. This enhanced thermophysical and heat transfer characteristics make ???uids embedded with nanomaterials as excellent candidates for future applications.