This book presents a theoretical study of heat transfer due to laminar
natural convection of nanofluids, using Al2O3-water nanofluid as an
example. An innovative method of similarity transformation of velocity
fields on laminar boundary layers is applied for the development of a
mathematical governing model of natural convection with actual
nanofluids, and a novel model of the nanofluid's variable thermophysical
properties is derived by a mathematical analysis based on the developed
model of variable physical properties of fluids combined with the model
of the nanofluid's thermal conductivity and viscosity. Based on these,
the physical property factors of nanofluids are produced, which leads to
a simultaneous solution for deep investigations of hydrodynamics and
heat transfer of nanofluid's natural convection.
The book also proposes novel predictive formulae for the evaluation of
heat transfer of Al2O3-water nanofluid's natural convection. The
formulae have reliable theoretical and practical value because they are
developed by rigorous theoretical analysis of heat transfer combined
with full consideration of the effects of the temperature-dependent
physical properties of nanofluids and the nanoparticle shape factor and
concentration, as well as variations of fluid boundary temperatures. The
conversion factors proposed help to turn the heat transfer coefficient
and rate of fluid natural convection into those of nanofluid natural
convection. Furthermore, several calculation examples are provided to
demonstrate the heat transfer application of the proposed predictive
formulae.
