Thermal analysis of a chemically reactive micropolar nanofluid flow over a stretching cylinder: Cattaneo–Christov double-diffusion approach

Boundary layer flow over stretching surfaces has gained major scientific attention because of its importance in industrial and biomedical applications. However, flow over curved surfaces remains largely underexplored. This article leverages the Buongiorno model and Cattaneo–Christov (CC) double diffusion to explore the stagnation point flow of a micropolar fluid along a vertical stretching cylinder. Additional consideration of chemically reactive fluid under activation energy makes the analysis novel and relevant. Similarity transformations are used to convert the governing partial differential equations (PDEs) into a system of ordinary differential equations (ODEs), which are then solved using the fourth-order Runge–Kutta technique with a shooting approach. The numerical solutions provided trends of velocity, microrotation, temperature, concentration, entropy generation, and Bejan number under a multitude of pertinent parameters graphically. The heat and mass transfer rates and skin friction at the boundary were also tabulated. Results indicate that thermophoresis and thermal radiation enhance temperature, while the curvature of the cylinder adversely affects microrotation, but improves skin friction. Thermophoresis raises concentration, but Brownian motion lowers it. The temperature is lowered and raised by thermal and concentration relaxation parameters, respectively. The accuracy of the findings is confirmed by validation against the body of existing literature. Potential uses for this research include tailored medication administration and cancer treatments, including chemotherapy.