DNS OF TURBULENT HEAT TRANSFER IN A CHANNEL FLOWWITH VELOCITY SLIP CONDITION

The fully-developed turbulent heat transfer in a plane channel flow is studied via the direct numerical simulation technique. A linear velocity slip boundary condition is assumed on the top wall of the channel whereas the classical no-slip condition is imposed on the bottom wall. A first kind temperature boundary condition is assumed on both walls without temperature jump at the slip wall. Periodicity is imposed on other directions of the channel. Various statistical quantities are shown and discussed. In general, it is observed that the turbulence intensities, i.e. velocity fluctuations, are attenuated in the proximity of the slip wall while they are amplified in the vicinity of the no-slip wall. The behavior is somewhat different for the temperature fluctuations. The temperature fluctuations are amplified near the slip wall whereas they are attenuated close to the no-slip wall.

Keywords:

direct numerical simulation , turbulent heat transfer , channel flow , velocity slip condition , hydrophobic wall