Viscous dissipation in the heat transfer between a rotating cylinder and viscous media under forced convection

Abstract

The effects of viscous energy dissipation on the forced convection heat transfer between an unconfined rotating isothermal circular cylinder and surrounding viscous fluids are numerically investigated. The heat transfer characteristics are investigated for the range of conditions of the Reynolds number Re = 1-40, Prandtl number Pr = 1-100 (the Peclet number ranges between 1 and 4000), dimensionless rotational velocities α = 0-3, and Brinkman number Br = 0-1. For the steady flow regime, the isotherm patterns are presented for the range of values of Reynolds number, Brinkman number, Prandtl number, and rotational velocity. For low Peclet numbers (Re × Pr), the heat generated by the viscous dissipation is not efficiently removed which, promotes the appearance of hot spot zones. The variation of the local and average Nusselt numbers on the cylinder surface shows the effects of Brinkman number, Prandtl number, and rotational velocity on heat transfer between a rotating isothermal cylinder and a viscous flow for the range of conditions studied.

Keywords

• Viscous heating
• Rotating cylinder
• Nusselt number
• Brinkman number