Unsteady MHD hybrid nanofluid flow towards a horizontal cylinder

Transport phenomena near the stagnation region are common in the manufacturing industry, especially in polymer and extrusion processes, which need continuous improvement to enhance the process's quality standard. Hence, the present numerical investigation aims to test the performance of unsteady stagnation-point flow past a stretching/shrinking horizontal cylinder in a hybrid nanofluid. The impact of a magnetic field on the boundary layer flow is also considered. The mathematical model that had been simplified is solved numerically via the MATLAB bvp4c procedure. Several decisions have arisen from the numerical findings of this study. The results reveal that as the concentration of nanoparticle volume fraction increases, which infers the transition of nano-fluid to hybrid nanofluids, a 2% increment in heat transfer rate is observed. The unsteadiness parameter clearly improves thermal performance by a 50:50 mixing ratio containing 2% of copper and alumina nanoparticles. Furthermore, increasing the curvature parameter evidently increases thermal efficiency by approximately 22.8%. On the other hand, increasing the magnetic parameter deteriorates thermal properties, leading to a drastic reduction in the heat transfer rate up to 32.6%. Finally, the initial solution's stability is confirmed by the stability analysis.

Automated summary

This study numerically investigates the unsteady stagnation-point flow past a stretching/shrinking horizontal cylinder, considering the impact of a magnetic field. The results indicate that increasing the concentration of nanoparticles and altering the mixing ratio can enhance heat transfer efficiency, while increasing the magnetic parameter leads to a decrease in heat transfer rate.