Abstract
To investigate the heat transfer characteristics of a package in a refrigerating room with downflow, the temperature distribution and heat transfer coefficient were measured in the case where one wall of the vertical duct was isothermally heated and gas flowed downward through the duct in the laminar flow range as a model of the package wall in a refrigerating room.
The temperature distribution is nearly uniform except near the heated surface and confront plate. The cross-sectional temperature gradient near the heated surface becomes steep with decreasing Reynolds number of the ambient fluid. The effect of free convection on average Nusselt number is large in the range of low Reynolds number and becomes small with increasing Reynolds number. An empirical equation for heat transfer was obtained within the operating conditions of this experiment.
