*Article* **Entropy Optimization on Axisymmetric Darcy–Forchheimer Powell–Eyring Nanofluid over a Horizontally Stretching Cylinder with Viscous Dissipation Effect**

**Muhammad Rooman 1,2, Muhammad Asif Jan 2, Zahir Shah 1,\*, Narcisa Vrinceanu 3,\*, Santiago Ferrándiz Bou 4, Shahid Iqbal <sup>5</sup> and Wejdan Deebani <sup>6</sup>**


**Abstract:** The effect of entropy optimization on an axisymmetric Darcy–Forchheimer Powell–Eyring nanofluid flow caused by a horizontally permeable stretching cylinder, as well as non-linear thermal radiation, was investigated in this research work. The leading equations of the current problem were changed into ODEs by exhausting appropriate transformations. To deduce the reduced system, the numerical method bvp4c was used. The outcome of non-dimensional relevant factors on velocity, entropy, concentration, temperature, Bejan number, drag force, and Nusselt number is discussed and demonstrated using graphs and tables. It is perceived that, with a higher value of volume fraction parameter, the skin friction falls down. Likewise, it is found that the Nusselt number drops with enhancing the value of the volume fraction. Moreover, the result reveals that the entropy generation increases as the volume fraction, curvature parameter, and Brinkman number increase.

**Keywords:** heat transfer; stretching cylinder; nonlinear radiation; Powell–Eyring; nanofluid; porous medium; Darcy–Forchheimer
