Numerical Simulation of Forced Convection of Nanofluids by a Two-Component Nonhomogeneous Model

Nanofluids, in which nano-sized particles (typically less than ۱۰۰ nm) are suspended in liquids, have emerged as a possible effective way of improving the heat transfer performance of common fluids. In this paper a numerical study is performed to analyze the wall shear stress and heat transfer coefficient of γAl۲O۳-water nanofluids under laminar forced convection through a circular pipe. It is assumed that the distribution of nanoparticles in the flow field is nonhomogeneous. The results obtained show that addition of γAl۲O۳ nanoparticles to pure water effectively enhances the convective heat transfer. Moreover, the wall shear stresses are increased. The increasing rate of heat transfer depends on the volume concentration such that for the lowest and highest values of particle volume concentration ۰.۰۳ and ۰.۰۵, considered in this study, the heat transfer enhancement is approximately ۲۳% and ۴۰%, respectively. Also, compared with the available experimental data, the model used in this work is capable to predict the increasing rate of heat transfer of nanofluids properly.

کلیدواژه ها:

Nanofluids ، Heat transfer enhancement ، Non ، Uniform Particle Distribution ، Two ، Component Model ، Constant Wall Temperature