Effect of Parameters of Rotating Cylinders on the Heat Transfer Advancement

Abstract

Conjugate pure mixed convection in a differentially heated square cavity with two vertically placed heat conductive revolving cylinders has been analyzed in a computational approach applying the finite element method. This analysis has been implemented considering the upper and lower wall as insulated simultaneously and the left vertical wall as heated maintaining constant temperature (i.e., isothermally heated) and the right vertical wall as isothermally cooled. The outcomes of this study have been examined concerning streamlines, isotherms, average Nusselt number (Nu) which unveils a noteworthy fact that both the rotating cylinders' inclination patterns and Reynolds number (Re) have a vital role upon the average Nusselt number (Nu), flow pattern, and isotherms. From that perspective, best heat transfer phenomena have been observed for counterclockwise circulation of both cylinders so that the condition for these cases has been assessed from a distance variation between the two cylinders maintaining a constant speed ratio (Ω). Moreover, the best result from this assessment has been trialed changing the type of materials of the rotating cylinders and ultimately, the best one has been specified as well as tested for various speed ratios. In the end, the results have been compared with the stationary cylinders where a similar type of results have been observed, but for rotating ones, Nusselt number (Nu) has been observed higher than stationary ones.