Hybrid Nanofluid Flow On A Shrinking Cylinder With Prescribed Surface Heat Flux

• Main Authors: Waini, Iskandar, Ishak, Anuar, Pop, Ioan Mihai
• Format: Article
• Language: English
• Published: Emerald Group Holdings Ltd. 2020
• Online Access: http://eprints.utem.edu.my/id/eprint/25277/2/WAINI2020%20HFF%20CYLINDER%20PHF.PDF; http://eprints.utem.edu.my/id/eprint/25277/; https://www.emerald.com/insight/content/doi/10.1108/HFF-07-2020-0470/full/html

Purpose: This study aims to investigate the flow impinging on a stagnation point of a shrinking cylinder subjected to prescribed surface heat flux in Al2O3-Cu/water hybrid nanofluid. Design/methodology/approach: Using similarity variables, the similarity equations are obtained and then solved using bvp4c in MATLAB. The effects of several physical parameters on the skin friction and heat transfer rate, as well as the velocity and temperature profiles are analysed and discussed. Findings: The outcomes show that dual solutions are possible for the shrinking case, in the range (Formula presented.), where (Formula presented.) is the bifurcation point of the solutions. Meanwhile, the solution is unique for (Formula presented.). Besides, the boundary layer is detached on the surface at (Formula presented.), where the value of (Formula presented.) is affected by the hybrid nanoparticle (Formula presented.) and the curvature parameter (Formula presented.). Moreover, the friction and the heat transfer on the surface increase with the rising values (Formula presented.) and (Formula presented.). Finally, the temporal stability analysis shows that the first solution is stable in the long run, whereas the second solution is not. Originality/value: The present work considers the problem of stagnation point flow impinging on a shrinking cylinder containing Al2O3-Cu/water hybrid nanofluid, with prescribed surface heat flux. This paper shows that two solutions are obtained for the shrinking case. Further analysis shows that only one of the solutions is stable as time evolves.