Wall temperature experimental investigation in a thermally driven channel

Direct local wall temperature has been measured, in a steady state, along a vertical air channel asymmetrically heated with uniform fluxes. In the ran ge of high Grashof numbers that was investigated, the flow regime probably remained laminar. A radiative part has been analysed with two extreme value s of internal surface emissivity corresponding to unpainted metal and black painted wall. A correlation has been proposed for the calculation of a cha racteristic channel outlet value of the Nusselt number referred to air spac ing: A local Nusselt number over the height has been developed in a power l aw scheme. (C) 1999 Elsevier Science Ltd. All rights reserved.