The heat conduction mechanism in nanofluid suspensions is derived for transient processes attempting to explain experimental results, which reveal an impressive heat transfer enhancement. In particular, the effect of the surface-area-to-volume ratio (specific area) of the suspended nanoparticles on the heat transfer mechanism is explicitly accounted for, and reveals its contribution to the specific solution and results. The present analysis might provide an explanation that settles an apparent conflict between the recent experimental results in nanofluid suspensions and classical theories for estimating the effective thermal conductivity of suspensions that go back more than one century (Maxwell, J.C., 1891, Treatise on Electricity and Magnetism). Nevertheless, other possible explanations have to be accounted for and investigated in more detail prior to reaching a final conclusion on the former explanation.
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