Boundary layer flow and heat transfer due to permeable stretching tube in the presence of heat source/sink utilizing nanofluids

The present study aims to identify effects due to uncertainties of thermal conductivity and dynamic viscosity of nanofluid on boundary layer flow and heat transfer characteristics due to permeable stretching tube in the presence of heat source/sink. Water-based nanofluid containing various volume fractions of different types of nanoparticles is used. The nanoparticles used are Cu, Ag, CuO, and TiO₂. Four models of thermal conductivity and dynamic viscosity depending on the shape of nanoparticles are considered. The results are presented to give a parametric study showing influences of various dominant parameters such as Reynolds number, the suction/injection parameter, solid volume fraction of nanoparticles, type of nanoparticles, the heat generation/absorption parameter and skin friction coefficient. The results indicate that the skin friction coefficient decreases as the Reynolds number and the suction/injection parameter (γ) increase, while the local Nusselt number increases as the Reynolds number and the suction/injection parameter (γ) increase. The results are compared with another published results and it found to be in excellent agreement.