Hybrid nanofluid flow and heat transfer past a vertical thin needle with prescribed surface heat flux
International Journal of Numerical Methods for Heat & Fluid Flow
ISSN: 0961-5539
Article publication date: 15 August 2019
Issue publication date: 21 November 2019
Abstract
Purpose
The purpose of this paper is to study the steady mixed convection hybrid nanofluid flow and heat transfer past a vertical thin needle with prescribed surface heat flux.
Design/methodology/approach
The governing partial differential equations are transformed into a set of ordinary differential equations by using a similarity transformation. The transformed equations are then solved numerically using the boundary value problem solver (bvp4c) in Matlab software. The features of the skin friction coefficient and the local Nusselt number as well as the velocity and temperature profiles for different values of the governing parameters are analyzed and discussed.
Findings
It is found that dual solutions exist for a certain range of the mixed convection parameter where its critical values decrease with the increasing of the copper (Cu) nanoparticle volume fractions and for the smaller needle size. It is also observed that the increasing of the copper (Cu) nanoparticle volume fractions and the decreasing of the needle size tend to enhance the skin friction coefficient and the local Nusselt number on the needle surface. A temporal stability analysis is performed to determine the stability of the dual solutions in the long run, and it is revealed that only one of them is stable, while the other is unstable.
Originality/value
The problem of hybrid nanofluid flow and heat transfer past a vertical thin needle with prescribed surface heat flux is the important originality of the present study where the dual solutions for the opposing flow are obtained.
Keywords
Acknowledgements
The authors wish to express their thanks to the Reviewers for their constructive comments and suggestions. The financial supports received from the Universiti Kebangsaan Malaysia (Project Code: DIP-2017-009), Universiti Teknikal Malaysia Melaka and the Ministry of Education, Malaysia are gratefully acknowledged. The work of Ioan Pop was supported by the grant PN-III-P4-ID-PCE-2016-0036, UEFISCDI of Romanian Ministry of Sciences.
Competing Interests: The authors declare no competing interests.
Citation
Waini, I., Ishak, A. and Pop, I. (2019), "Hybrid nanofluid flow and heat transfer past a vertical thin needle with prescribed surface heat flux", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 29 No. 12, pp. 4875-4894. https://doi.org/10.1108/HFF-04-2019-0277
Publisher
:Emerald Publishing Limited
Copyright © 2019, Emerald Publishing Limited