Quadratic combined convective flow about yawed cylinder in presence of time variations and magnetic effects: entropy analysis

Abstract

The significance of time-dependent variations in a quadratic combined convective magnetohydrodynamic (MHD) flow around an infinite yawed cylinder with entropy analysis is explored in the present investigation. There are numerous real-world applications wherein the yawed-shaped bodies are used extensively, for example, overhead cables, bridge stay cables, chimney stacks etc. First, the dimensional governing equations are made dimensionless by applying the appropriate transformations of non-similar nature. After that, using the Quasilinearization technique, the resulting equations are linearised and discretized by employing implicit finite difference approximations. In unsteady flow, velocity distributions along chordwise and spanwise directions reduced when compared with the steady case. As the cylinder's yaw angle grows, fluid pressure inside it rises, increasing its velocity in all directions. The surface drag coefficients along chord & spanwise directions and the energy transfer rate increase approximately by 104%, 67% and 40%, respectively, as $Ri$ increases from −2 to 10, for accelerating flow $\left(\alpha >0\right)$ at $\theta ={45}^0$ and $\tau =1$. An increase in the yaw angle results in more entropy generation (EG). It shows that yawed cylinder overcomes the EG difficulties faced in the case of a vertical cylinder. It is revealed that, by using a yawed cylinder with MHD, one can restrict the amount of energy loss.

KEYWORDS:

• Unsteady flow
• yawed cylinder
• entropy generation
• finite difference scheme
• magnetohydrodynamics (MHD)
• quadratic combined convection

Acknowledgement

The second author is thankful for the support (in terms of Fellowship) to the Department of Science and Technology-Innovation in Science Pursuit for Inspired Research (DST-INSPIRE), New Delhi.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Department of Science and Technology, Ministry of Science and Technology [grant number DST/INSPIRE Fellowship/2019/IF190225].