Transfert de chaleur au voisinage du point de recollement en aval d'une marche descendante

Abstract

It has been noticed, although not yet explained, that in recirculating flows the heat transfer coefficient, which is maximum in the reattachment zone, does not correspond in position with the mean reattachment point. We propose an explanation based on impact (main component of velocity V < 0) and sweeping (main component of velocity U > 0) phenomena which are both induced by the vortical structures interacting with the heated wall. This approach uses information given by a numerical code based on the finite volume technique, as well as an analysis of the time evolution of the reattachment point X r and the point of maximum heat transfer X max . This analysis is supported by the time series and the profiles of the correlations relative to the velocities and temperature variables.