Temperature wall modelling for large-eddy simulation in a heated turbulent plane channel flow

Industrial flows are often wall-bounded, characterized by a high Reynolds number turbulence and a strong unsteadiness. Large-eddy Simulations applied to this kind of flows require a heavy mesh resolution which is out of reach of the nowadays computational power. Wall models are usually used to alleviate this constraint. However, very few of them are dedicated to the temperature field. Besides, most of these wall models are based on equilibrium laws which are not able to take into account the unsteadiness of the flow in the near-wall region. In this study, an original thermal wall model, inspired from the TBLE wall model of Balaras et al. [E. Balaras, C. Benocci, U. Piomelli, Two-layer approximate boundary conditions for large-eddy simulations, AIAA J. 34 (6) (1996) 1111-1119], is developed and implemented in the CEA (French Atomic Center) Trio_U code and assessed on a heated and turbulent plane channel flow configuration. The investigated friction Reynolds numbers are 395, 1020 and 4800, and the Prandtl number is taken equal to 0.71.