DNS of turbulent channel flow: can we imitate conjugate heat-transfer with a Robin boundary condition?
Résumé
Turbulent heat fluxes, temperature variance and associated budgets obtained from the Direct Numerical Simulation of an incompressible turbulent channel flow with a Reynolds number of 150, based on the wall friction velocity, and a Prandtl number of 0.71 are presented and analysed for four cases : imposed temperature at the wall (Dirichlet), imposed heat flux (Neumann), heat exchange coefficient (Robin) and 3D conjugate heat transfer. Present results show that a Robin boundary condition can imitate most of the one point statistics obtained with conjugate heat-transfer accurately compared to the statistics obtained with an imposed temperature or heat flux at the wall.