Melting Heat Transfer of Frozen Porous Media around Cylinders in an Enclosure.

Abstract

Melting heat transfer of ice in porous media around a single horizontal cylinder and two horizontal cylinders vertically spaced in a rectangular enclosure has been experimentally and numerically investigated. In the experiments, an ice saturated porous medium was set at-1.0°C, and the temperature of the cylinder surfaces was changed above the fusion temperature, 0°C, and then melting was initiated. Melting of pure ice without porous media was also studied in order to compare to the case with the porous media. As a result, it was seen that natural convection largely affected melting of pure ice without the porous media even for the small cylinder-temperatures, 4.0°C and 8.0°C, but with the small porous particles(d=1.0mm)the effect did not largely appear even for the large cylinder-temperature, 20.0°C. On the other hand, with the large porous particles(d=5.0mm)the effect is clearly observed for 20.0°C. The melt area ratios were not largely changed with a change in the number of cylinders, although the melt shapes were largely changed after melted regions around the two cylinders were merged. Numerically obtained temperature distributions and melt area ratios were in good agreement with the experimental ones. In addition, timewise variations of velocity distribution in melt were clarified by the calculations.