The effect of internal plate vibration on the rate of heat transfer in a glass recycling process dryer

Abstract

This study concerns with the effect of transverse vibration of an internal plate on mixed convection heat transfer inside a square enclosure of a glass recycling process dryer. The plate can oscillate in horizontal and vertical directions. The Reynolds-averaged Navier-Stokes equations are used to describe the unsteady turbulent flow field. The governing equations are solved numerically applying a finite-volume approach. OpenMP Parallel SIMPLE algorithm is employed with power-low scheme for the convective terms. Also, the turbulent flow properties are estimated by a two-layer zonal model based on k−εmodel and Wolfstein near wall treatment. Dimensionless effective parameters including Reynolds number (Re), Grashof number (Gr) and vibration angular frequency (ω) are varied to investigate inherent flow structures and the heat transfer rate. It was deduced from the results that at high Gr and low Re numbers, the effect of internal plate vibrations is negligible and the fluid flow is induced only by the buoyancy force. As Re and ω are increased, the effect of internal plate vibration becomes dominant. At high Re and ω values while Gr kept low, benchmark cavity heat transfer is increased up to 90 and 80 times due to the vibration of internal horizontal and vertical plates, respectively. The obtained results can be beneficial for the dryers of glass recycling industries in order to heat and smash the glass particles without a significant heat loss. Desired condition occurs at high Gr and ω when the flow Re number is comparatively low.