Home – Home – Jornals – Thermophysics and Aeromechanics 2015 number 6

In the present paper, we consider one of the most efficient and simple methods to additionally intensify the exchange processes and heat transfer in the separated flow behind a backward-facing step. The method uses small obstacles installed upstream the step; such obstacle act as turbulators smaller in size than the main obstacle. As the turbulators, solid mini ribs, comb ribbings, and wall-detached mini ribs were used. Intensification of the turbulent mixing process behind the main obstacle occurs due to the introduction of small-obstacle-induced 2D and 3D perturbations into the separated shear layer behind the step. Results of a detailed experimental study of the distributions of pressure and heat transfer for different heights of the small intensifier and its positions with respect to the step are reported. The influence of intensifier shape on the thermal and dynamic characteristics of the flow has been analyzed. The distributions of pressure and heat-transfer coefficients were used to evaluate the effectiveness of the various mini ob-stacles and the limits of their action on the drag and heat transfer.