Investigation on the preparation and thermal properties of Ag-H 2O nanofluids with different morphology

The triangular flake and wire shaped silver-water (Ag-H2O) nanofluids with good suspension have been achieved via one-step and two-step method, respectively. The thermal conductivity and viscosity of two kinds of Ag-H2O nanofluids were both higher than the based fluids (H2O). The results showed that the thermal conductivity of the two kinds of Ag-H2O nanofluids increased with the content of Ag nanoparticles and temperature increasing. The rheological behaviours analysis showed that two kinds of Ag-H2O nanofluids observed the Newtonian behaviours whose viscosity were close to the water and increased with Ag incorporation. The thermal conductivity of the triangular flake shaped nanofluids was higher than that of the wire shaped nanofluids in the same mass fraction and temperature while the viscosity was in reverse. The effect mechanism of solid content, temperature and morphology on the thermal property of Ag-H2O nanofluids has been discussed in detail.