An overview of non-Newtonian nanofluid flow in macro- and micro-channels using two-phase schemes

This review paper provides an overview of heat transfer of non-Newtonian nanofluids flowing in macro-and micro-channels using single-phase and two-phase approaches. This paper addresses governing equations for different types of non-Newtonian fluids and provides several advances in the field. The single-phase and two-phase schemes are described and their advantages and drawbacks in the simulation of non-Newtonian nano-fluids in macro-and micro-channels are introduced. It is demonstrated that single-phase approaches cannot provide precise predictions due to the lack of accurate correlations because effective parameters change with the properties of nanofluids. The literature review indicates that the distribution of nanoparticles in the base fluid should be recognized properly. Understanding the concentration of nanoparticles and also their migration in channels or ducts results in demonstrating the formation of nanoparticle clustering. It is revealed that almost all investigators utilize the power-law model to simulate non-Newtonian nanofluid flow in macro-and micro-channels. According to the discussion presented in the paper, perspectives and future direction are provided.