Heat transfer regulation in a rectangular enclosure using a rotating plate

Abstract

The effects of an inner rotating plate with horizontal axis on the heat transfer in a differentially heated vertical enclosure were investigated experimentally. The aspect ratio of the enclosure height/width was 1 throughout the experiments. An acrylic plate with a small thermal conductivity was installed horizontally at the center of the square enclosure, and was rotated at various speeds for normal and reverse rotations by using the motor attached outside of the enclosure. Purified water was used as the working fluid. The flow pattern was sketched by a visualization experiment using aluminum powder. The heat transfer results were also compared with those from a previous paper on a rotating cylinder. It is clarified here that the heat transfer rate of the enclosure depends largely on the parameter Grw/Re2w, and is characterized by three regions. The heat transfer rate of the enclosure with a rotating plate is somewhat larger than that of a rotating cylinder in the forced convection region. The rotating plate used here will be useful for regulation of wide-ranging heat transfer. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(4): 342-353, 2003; Published online in Wiley InterScience (www.interscience.wiley.com).