International Journal of Heat and Mass Transfer, Vol.55, No.4, 726-733, 2012
Heat transfer in turbulent separated flow behind a rib on the surface of square channel at different orientation angles relative to flow direction
Experimental results on turbulent streamlining of a flat rib on a flat surface at a change in the rib orientation angle relative to the flow are presented in this paper. Experiments were carried out for angles phi varying from 50 degrees to 90 degrees and three values of rib height. Data on visualization were used for determination of the pattern of vortex formation and coordinates of reattachment line. Deformation of the recirculation region and obvious 3D character of the flow behind the rib with a decrease in angle phi considered. The pressure coefficients were measured in different longitudinal cross-sections of the channel behind the rib with varying orientation angle phi. The temperature fields on the surface behind the rib were determined by means of the thermography method and with the help of thermocouples. The effect of the angle of flow angularity and rib height on dynamic and thermal characteristics of the separated flow was analyzed. (C) 2011 Elsevier Ltd. All rights reserved.
Keywords:Rib;Orientation angle;Turbulent separated flows;Enhancement;Heat transfer;Pressure distribution