Experimental study on flow behavior of SiO₂-water nanofluids in a wavy-walled tube

Experiments were carried out on flow behavior of different mass concentrations SiO₂-water nanofluids in a wavy-walled tube, due to the structure characteristics of the wavy-walled tube, the fluid can turn to turbulent area in smaller Reynolds numbers and the flow structure characteristics in the laminar, transitional and turbulent flow region can be easily measured. The result show that the viscosity of the nanofluids increases with the mass concentrations of nanoparticles in the same temperature; the flow visualization shows that the nanofluids have better uniformity due to the micro-movements of the nanoparticles; the result of resistance tests show that the friction factor of nanofluids increases with the mass concentrations of nanoparticles in the laminar flow region and the friction factors of nanofluids have almost no change with the mass concentrations of nanoparticles in the transitional and turbulent flow region.