Semarak Engineering Journal

Advancing Heat Transfer: Exploring Nanofluids and Regression analysis on Lower Stagnation Point of a Horizontal Circular Cylinder for Brinkman-Viscoelastic Fluid

Farahanie Fauzi — 2024-12-31

Nanofluids and hybrid nanofluids are increasingly employed in research, products, and technologies to enhance heat transfer efficiency. Recent investigations have focused on the convective heat transfer of viscoelastic nanofluids flowing through porous media, utilizing the Brinkman-Viscoelastic nanofluid model. In this study, the volume fraction of nanoparticles is used to characterize the nanofluids, while the heat transfer performance is quantified by the Nusselt number. The primary objective is to develop a regression model that evaluates the influence of nanoparticle volume fraction on the Nusselt number using simple linear regression analysis. Copper (Cu) nanoparticles and Carboxymethyl Cellulose (CMC) serve as the nanoparticle and base fluid, respectively. The governing equations for Brinkman-Viscoelastic nanofluid are simplified through non-dimensional and non-similarity transformations to enable analytical treatment. These simplified equations are numerically solved using the Runge-Kutta-Fehlberg method, and the results are used to construct and validate the regression model. This study provides insights into the relationship between nanoparticle concentration and thermal performance, contributing to advancements in heat transfer applications.

The Importance of Adopting Response Surface Methodology to Optimize the Flow and Heat Transfer of Carbon Nanotube Nanofluid over a Stretching or Shrinking Sheet

Nazrul Azlan Abdul Samat — 2024-12-31

The research investigates the boundary layer flow and heat transfer of carbon nanotube (CNT) nanofluid over a stretching/shrinking sheet with the magnetohydrodynamic (MHD) effect. The purpose of constructing this model is to increase the understanding of CNT nanofluid flow and heat transfer characteristics since numerous models use metallic nanoparticles. We conduct this study using numerical and response surface methodology (RSM) approaches in MATLAB and Minitab, respectively. We formulate the mathematical formula by applying the non-linear partial differential equations (PDE). Next, we transform the PDE into non-dimensional ordinary differential equations (ODE) by exploiting the similarity variables method. We show that the model produces multiple solutions in the shrinking region. The magnetic parameter can widen the solutions and delay the boundary layer separation. Both numerical and RSM methods reveal that the maximum value of the magnetic parameter maximizes the heat transfer coefficient. Additionally, both methods demonstrate that single-walled CNT nanofluid is better than multi-walled CNT nanofluid in transmitting heat.

Magnetohydrodynamic of Williamson Hybrid Nanofluids Flow Over a Non-Linear Shrinking Sheet with Viscous Dissipation and Joule Heating

Masyfu’ah Mokhtar — 2024-12-31

Heat transfer plays a crucial role in various industrial applications. Thus, this study investigates the heat transfer characteristics of a non-Newtonian Williamson hybrid nanofluids flowing over a non-linear shrinking sheet, incorporating MHD effects and viscous dissipation. Alumina and Copper nanoparticles are dispersed in a CMC-water base fluid, representing a non-Newtonian hybrid nanofluid with shear thinning behaviour. The complex mathematical model is transformed into similarity equations using appropriate transformations, and the MATLAB function bvp4c is employed to solve these equations numerically. The model’s accuracy is validated by comparison with an established model, demonstrating reasonable agreement. The study analyses the impact of various fluid parameters, including magnetic, Eckert number, Williamson, suction, and nanoparticle volume fraction, on fluid flow behaviour. Results show that increased suction enhances both the skin friction coefficient and heat transfer rate, while a higher Williamson parameter reduces both. The heat transfer rate decreases with an increase in the Eckert number. Additionally, an increase in the magnetic parameter and nanoparticle volume fraction leads to higher skin friction but a lower heat transfer rate.