Mohammad Saeedinia - Dept. of Mechanical Engineering, College of Engineering, University of Tehran,
M.A Akhavan-Behabadi - Dept. of Mechanical Engineering, College of Engineering, University of Tehran
Pooyan Razi - Dept. of Mechanical Engineering, College of Engineering, University of Tehran

In the present experimental investigation, stable CuOBase oil nanofluids with different particle weight fractions of 0.2%, 0.5%, 1% and 2% are prepared and their thermal characteristics and rheological behavior are studied. Thermal conductivities, viscosities and specific heat capacities of base fluid and all nanofluids at different temperatures are measured and the effect of nanoparticles concentration on fluid properties is investigated.Experimental results clearly indicate that addition of nanoparticles into the base fluid enhances the thermal conductivity of the fluid and the enhancement increases with increasing of particle concentration. The maximum thermal conductivity increasing of 6.2% is achieved for nanofluid with 2% weight fraction. For the particle concentrations tested, nanofluids exhibits Newtonian behavior. It is seen that the dynamic viscosity substantially increases the increase of nanoparticle concentration and this increase is more pronounced in the lower temperatures of the nanofluid. The specific heat capacity of nanofluids is significantly less than that of base fluid and it is decreased with the increase of nanofluid concentration. The specific heat capacity of nanofluid with 2% weight fraction is about 23% lower than that of the base fluid at 40°C.

Rheological behavior, CuO, Base Oil,Thermal characteristic, Nanofluid