Comparative Study of Heat Transfer and Friction Factor Characteristics of Nanofluids in Rectangular Channel

This paper reports numerical study of heat transfer and friction factor of laminar flow nanofluids characteristics in a rectangular channel. The effectiveness of metal oxide nanoparticles(Al2O3), metal nanoparticles (Cu) and semiconductor nanoparticles (SiO2)in enhancing heat transfer rate were studied by varying volume fractions in the range of 0.5% to 2.5% with constant nanoparticle diameter of 25nm. Numerical method was used to solve the three-dimensional laminar flow and heat transfer governing equation. The computations were performed under constant heat flux (18,000W/cm2) over range of Reynolds number (Re) 100 -1,000 laminar flow. The performances of nanofluids were evaluated in terms of velocity profile, heat transfer coefficient, pressure drop, and friction factor. The numerical results show that the heat transfer coefficients, thermal conductivity, pressure drop and mean velocity for all nanofluids increased with increasing Reynolds number as well as particle volume concentration, while the friction factor decreased.