Heat transfer past rotationally oscillating circular cylinder heated with time‐periodic pulsating temperature in a uniform flow: Fid-Bau Portal

Heat transfer past rotationally oscillating circular cylinder heated with time‐periodic pulsating temperature in a uniform flow

Ray, Rajendra K. / Haty, Amarjit / Kumar, Atendra

Abstract

The transient forced convection heat transfer from an impulsively started rotationally oscillating circular cylinder, heated with time‐periodic pulsating temperature in a two‐dimensional uniform, laminar and viscous flow of Newtonian, incompressible, constant property fluid is investigated in this paper. The two‐dimensional Navier‐Stokes and energy equations are solved using a higher‐order compact (HOC) finite difference scheme on non‐uniform polar grids. Computational code for solving the problem is written in C programming language and is validated against existing research works. The flow and heat transfer characteristics are mainly influenced by the amplitude of time‐periodic pulsating temperature ( $a$ ), period of time‐periodic pulsating temperature ( $P$ ), Prandtl number ( $P r$ ), Reynolds number ( $R e$ ), and cylinder oscillation parameters i.e. maximum rotational rate ( $α_{m}$ ), frequency ratio ( $f ∕ f_{0}$ ). The numerical computations are done for the range of parameter values $80 \leq R e \leq 200$ , $0.1 \leq a \leq 1.5$ , $0.01 \leq P \leq 100$ , $0.5 \leq α_{m} \leq 4$ , $0.5 \leq f ∕ f_{0} \leq 3$ and $P r = 0.7$ . The backward heat transfer is observed for certain values of the amplitude of time‐periodic pulsating temperature $a$ and the amount of backward heat transfer enhances with increasing amplitude of temperature. High period value ( $P = 100$ ) of pulsating temperature is found to reduce the amount of heat convection downstream. The influence of pulsating temperature is discussed for an increase or decrease in heat transfer rate relative to the constant cylinder‐temperature case.