Study of the influence of TiO₂ nano-particles on the rheology and heat conduction coefficient characteristics of a phase-change suspension

By using an experimental method, studied were the viscosity and heat conduction coefficient of a phase-change suspension after it has been mixed with TiO₂ nano-particles. The research results show that when the concentration of the nano-particles does not exceed 5%, the suspension can still be viewed as a Newtonian fluid and its viscosity will increase nonlinearly with an increase of the concentration of the nano-particles. When the concentration of the mass nano-particles equals to 5%, the viscosity of the phase-change suspension will rise by about 23%. The addition of the nano-particles is capable of significantly improving the heat conduction coefficient of the suspension in question. When the concentration of the nano-particles is 5%, the heat conduction coefficient of the phase-change suspension will increase by about 7%. When the concentration of the nano-particles is relatively low, the growth margin of the heat conduction coefficient of the phase-change suspension caused by the nano-particles will be higher than that of the water. The authors have analyzed from different perspectives the advantages of using the new type of suspension to serve as a heat transfer working medium.