Investigation of convective heat transfer from a plate having vertical periodic oscillation

In this study, effects on mixed convection heat transfer of periodic oscillations on a vertical flat plate were experimentally and numerically investigated. The experimental setup consists of a transparent enclosure, the experimental model moving within the enclosure, the flywheel-motor system for periodic motion of the experimental model, the data acquisition system and the computer. In the study, Rayleigh number (1.17×107≤ Ra ≤ 3.6×107), oscillation amplitude (0.4 ≤ Ao ≤ 1.4) and oscillation frequency (65 ≤ Wo ≤146) were changed. As a result of the experimental study, instant and average temperatures were obtained and heat transfer performance was calculated using these data. In addition, the effects of oscillation parameters on the Richarson Number (Ri) were analyzed. Total uncertainty analysis was calculated by determining the parameters causing uncertainty in the experimental study. For numerical studies, numerical simulations were performed by using ANSYS Fluent program based on Computational Fluid Dynamics (CFD) according to experimental data. As a result of the simulations, the mixed convection heat transfer on the plate surface was calculated and numerical results were compared with experimental results and widespread literature. In addition, instant velocity and temperature contours were obtained on the plate surface. As a result, the heat transfer obtained for the periodic oscillating vertical plate was higher than the heat transfer obtained for the fixed vertical plate. The heat transfer performance was significanly affected by the oscillation parameters and Ra numbers. The best heat transfer performance was obtained about 43 % at low Ra number (Ra = 1.17×107), high amplitude (Ao = 1.4) and high oscillation frequency (Wo=146).