Thermal patterns on the smooth and rough walls in turbulent flows

Here an experimental study of temperature fields on the surface of smooth a nd rough walls is dealt with, in turbulent channel and pipe flows. The hot- foil infrared technique was used to measure the local (instantaneous and ti me average) temperatures on the walls. The detailed data on mean and fluctu ation temperature distributions are presented. The temperature fields in th e vicinity of a single macroscale roughness (particle) as well as a lattice of particles are studied. (C) 1999 Elsevier Science Ltd. All rights reserv ed.