ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Effects of irregular heat sources and activation energy on Casson nanofluid flow: a Cattaneo–Christov heat flux approach

Sivaiah Sreeramula, B. Tulasi Lakshmi Devi, Devika Dabke, and P. Chandrakala

Vidya Jyothi Institute of Technology (A), Hyderabad, India

E-mail: drsiva1339@gmail.com

Received: 31 October 2025  Accepted: 29 November 2025

Abstract:

This investigation explores the magnetohydrodynamic convective heat transfer of Casson nanofluid flowing past a stretched cylinder within the context of the Cattaneo–Christov heat and mass flux model, considering the combined influences of activation energy, Brownian motion, thermophoresis, and variable heat sources. A principal characteristic of this research is the concurrent incorporation of these mechanisms within a Casson nanofluid system, providing a thorough depiction of non-Fourier heat conduction and reactive transport phenomena. The governing equations are reduced via similarity transformations and solved numerically using the Runge–Kutta shooting method and BVP4C in MATHEMATICA. Results indicate that velocity increases with the Casson parameter, Brownian motion, thermophoresis, Eckert number, activation energy, and heat sources. Temperature rises with Deborah numbers, while nanoconcentration decreases with the first Deborah number and increases with the second; activation energy lowers nanoconcentration. Heat transfer rates vary inversely with Deborah numbers. This novel integration of advanced heat flux modelling and activation energy provides valuable insights for optimising heat and mass transfers in chemical, energy, electronic, and biomedical systems.

Keywords: Cattano-Christov model; Activation energy; Brownian motion; Thermophoresis; Stretching cylinder; Heat transfer; Dissipation

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04570-y

Chemical Papers 80 (3) 3049–3063 (2026)