Heat and Mass Transfer in Fluids with Nanoparticle Suspensions

Abstract

This chapter presents a discussion on heat and mass transfer in fluids with nanoparticle suspensions. The fundamental laws of thermodynamics govern the transfer of heat and state that when a temperature gradient exists in a body, there is an energy transfer from the high-temperature region to the low-temperature region or from a region of high potential to a lower energy state. The effective thermal conductivity of nanoparticle suspensions is being studied both experimentally and theoretically. The experimental results have identified several areas in which there is a significant deviation from the theories developed to predict the effective thermal conductivity of micro- or millimeter-size particle suspensions. However, because the experimental data are limited, theoretical studies have not as yet been verified to the extent that they can provide the basis for a well-defined set of equations that could inform subsequent experimental research. The chapter presents various techniques for manufacturing ultrafine particles with unique physical and chemical properties. The chapter also presents a graphical representation of the thermal conductivity as a function of volume fraction of Al 2 O 3 powders in different fluids. The chapter tabulates the effective transport coefficient of different disperse systems and discusses the development of effective thermal conductivity equations. The chapter concludes with a discussion on the effects of the Brownian motion coupled with thermal phoresis.