ABSTRACT
Though attempts have been made to explain the physical reasons for such enhancement in nanofluids, there are still many conspicuous incon sistencies (Keblinski, Prasher, and Eapen 2008). There are at least four rea sons why a definitive theory on nanofluids still does not exist (Das et al. 2007; Wang and Fan 2010):
• The thermal behavior is too different from solid-solid composites or standard solid-liquid suspensions.