Comparison of Modified and Classical Hamilton-Crosser Models for MWCNT-Water Nanofluid Heat Transfer Rate

Abstract

The classical Hamilton-Crosser model is used to calculate the thermal conductivity of nanofluids. This thermal conductivity is controlled by the volume fraction of nanoparticles. However, the classical model encounters limitations when dealing with situations that include high concentrations of particles and a wide range of nanoparticle shapes. Researchers have acknowledged these limitations and have made modifications to the classical model to improve its accuracy and applicability. This research aims to compare the modified model with the classical Hamilton-Crosser model, focusing on the heat transfer rate of multi-walled carbon nanotube (MWCNT) water-based nanofluid. The governing equations were converted into ordinary differential equations using similarity variables and solved using the bvp4c function in MATLAB. The numerical solutions generated using bvp4c investigate the impact of a magnetic field, viscous dissipation, nanoparticle volume fraction, surface transpiration rate, length of MWCNT, and diameter of MWCNT. The findings suggest that the modified model reliably forecasts elevated heat transfer rates in comparison to the classical model. In addition, increased lengths of MWCNTs result in elevated rates of heat transfer. In contrast, as the diameter of MWCNTs increases, there is a progressive reduction in heat transmission rates. Therefore, the research suggests that the revised model is very well suited for identifying the ideal diameters of nanotubes to improve heat transfer efficiency. The results enhance the accuracy of thermal conductivity models and further the comprehension of nanofluid heat transfer properties.