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Free stream flow and forced convection heat transfer across a rotating circular cylinder have been investigated numerically for the range of Reynolds number between 5 and 40 (5 ≤ Re ≤ 40). The non-dimensional rotation rate, α is employed upto a maximum value of 5. The governing equations namely, continuity, momentum, and energy equations have been solved in 2D steady laminar flow regime for the range of Prandtl number between 0.7 and 67 (0.7 ≤ Pr ≤ 67). Uniform heat flux (UHF) and constant wall temperature (CWT) boundary conditions have been considered, separately, for the range of afore mentioned parameters. New results are presented depicting the behavior of temperature field around the cylinder rotating in a high Pr environment (Pr ≥ 33) with non-dimensional rotation rate in the range between 0 and 5 (0 ≤ α ≤ 5). It is noted that the heat transfer across the cylinder becomes increasingly independent of the thermal boundary condition i.e. UHF or CWT.

Thermomechanical stresses play an important role in defining the life of the work roll used in hot rolling process. In this research temperature dependent mechanical properties of cartridge brass are determined experimentally using high temperature compression tests at different temperatures and strain rates. Real life measurements are made from a brass rolling mill as input data for the simulation boundary conditions. Hot rolls are made of AISI H11 hot work tool steel. Temperature dependent mechanical properties of AISI H11 steel are used. Thermal and mechanical stresses produced in the work rolls during hot rolling process are predicted using a thermoplastic finite element approach in the ABAQUS Standard software. Hot rolling is compared with cold rolling to determine the effects produced on the work rolls. A criterion is introduced to compare the severity of stresses produced on the rolling surfaces in case of hot rolling and cold rolling based on the yield stress of the roller material for different temperatures. A method for separating thermal and mechanical stresses in the simulation is also described.

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