MHD rotating flow over a stretching surface: The role of viscosity and aggregation of nanoparticles

Aisha M Alqahtani; Khadija Rafique; Zafar Mahmood; Bushra R Al-Sinan; Umar Khan; Ahmed M Hassan

doi:10.1016/j.heliyon.2023.e21107

MHD rotating flow over a stretching surface: The role of viscosity and aggregation of nanoparticles

Heliyon. 2023 Oct 17;9(11):e21107. doi: 10.1016/j.heliyon.2023.e21107. eCollection 2023 Nov.

Authors

Aisha M Alqahtani¹, Khadija Rafique², Zafar Mahmood², Bushra R Al-Sinan³, Umar Khan², Ahmed M Hassan⁴

Affiliations

¹ Department of mathematical sciences, College of Science, Princess Nourah bint Abdulrahman University, P. O. Box 84428, Riyadh 11671, Saudi Arabia.
² Department of Mathematics and Statistics, Hazara University, Mansehra, Pakistan.
³ Department of Administrative and Financial Sciences, Nairiyah College, University of Hafr Al-Batin, Hafr Al-Batin 31991, Saudi Arabia.
⁴ Center of Research, Faculty of Engineering, Future University in Egypt, New Cairo, 11835, Egypt.

Abstract

The magnetohydrodynamic (MHD) rotating flow that occurs across a stretching surface has numerous practical applications in a variety of domains. These fields include astronomy, engineering, the material sciences, and space exploration. The combined examination of magnetohydrodynamics rotating flow across a stretching surface, taking into consideration fluctuating viscosity and nanoparticle aggregation, has significant ramifications across several different domains. It is essential for both the growth of technology and the attainment of deeper insights into the complicated fluid dynamics to maintain research in this field. Given the aforementioned motivation, the principal aim of this study is to examine the effects of variable viscosity on the bidirectional rotating magnetohydrodynamic flow over a stretching surface. Aggregation effects on nanoparticles are used in the analysis. Titania $(T i O_{2})$ is taken nanoparticle and ethylene glycol as base fluid. The nonlinear ordinary differential equations and the boundary conditions that correspond to them can be transformed into a dimensionless form by using a technique called similarity transformation. To get a numerical solution to the transformed equation, the Runge-Kutta 4th order (RK-4) method is utilized, and this is done in conjunction with the shooting method. The impact of various leading variables on dimensionless velocity, the coefficients of temperature, skin friction and local Nusselt number are graphically represented. Velocity profiles in both direction increases with increasing values of $φ$ . The Nusselt number increases with increasing values of the radiation and temperature ratio parameters. When a 1 % volume fraction of nanoparticles is introduced, the Nusselt number exhibits a 0.174 % increase for the aggregation model compared to the regular fluid in the absence of radiation effects. When the aggregation model is used with a 1 % volume fraction of nanoparticles, the skin friction increases by 0.1153 % in the x direction and by 0.1165 % in the y direction compared to the regular fluid. Tables show the variation in Nusselt numbers, as well as a comparison of the effects of nanoparticle's aggregation model without and with radiation. Moreover, the numerical results obtained were compared with previously published data, demonstrating a satisfactory agreement. We firmly believe that this finding will have extensive implications for engineering and various industries.

Keywords: Aggregation; Magnetohydrodynamics; Nanoparticles; Rotational flow; Stretching surface; Variable viscosity.