Convection laminaire ou turbulente de fluides thermodépendants. Cas de l'écoulement en canal de section rectangulaire

Abstract

This experimental study gives some information about flow and heat transfer, for two model fluids in a flat rectangular channel (aspect ratio 1/20) : on one hand, Newtonian thermodependent glucose syrups and, on the other hand, carboxymethylcellulose pseudoplastic thermodependent solutions. For laminar flow, thermodependence of fluids leads to a strong interaction between dynamical and thermal fields, including an increase in heat transfer, which must be compared to that of the velocity gradient. Heat transfer correlations have been established, taking account of imposed heat flux and thermodependence. For turbulent flow, the influence of thermodependence on the velocity field is very weak and the usual heat transfer correlations (Chilton-Colburn or Clapp) are available.