Effect of the type of thermal boundary conditions on heat transfer and skin-friction in a convergent channel

Investigation results on the airflow in a convergent channel with a hot bottom wall at a set constant heat flux or at a set constant wall temperature are presented. The numerical simulation was carried out in the OpenFOAM software using the k-ω-SST turbulence model. The verification of simulation results demonstrated a good agreement between the calculated data and the experimental velocity profiles and the thermal Stanton number. The study showed that an increase in the temperature of the convergent channel wall leads to the phenomenon of the streamwise velocity overshoot, suppression of turbulence and a decrease in the skin-friction coefficient and thermal Stanton number. In contrast to a zero pressure gradient flow, the type of thermal boundary conditions has a noticeable effect on the skin-friction and heat transfer in the convergent channel.