Review on Nanofluid Theoretical Viscosity Models

Much interest is shown on nanofluid as nanofluid is suitable for cooling applications. The two important thermo physical properties of nanofluid such as thermal conductivity and viscosity play key role in practical heat transfer situations. The nanofluid viscosity is investigated by many investigators next to the thermal conductivity of nanofluid as the viscosity determines the pumping power. This review summarizes the nanofluids theoretical viscosity models proposed by different research groups. Though many viscosity models formulated of nanofluids, there is no universally accepted model and reliable mechanism for viscosity over the particles volume fraction. Therefore this review leads to further investigation on the hotly debated topic of viscosity of nanofluids.