EXPERIMENTAL-ANALYSIS OF HEAT-TRANSFER WITH PHASE-CHANGE IN POROUS-MEDIA CROSSED BY A FLUID-FLOW

Experimental analysis of the heat transfer in an unconsolidated porous medium was conducted. A fluid flowed through the medium in an upward direction. The fluid was heated by one or both of the vertical sides. Several flow and thermal configurations were examined, single-phase and phase-change. Experimental analysis was carried out on the set of temperature values measured throughout the enclosure. All the temperatures in the medium were evaluated by using polynomial fitting from local readings. The validity of the technique is confirmed by the good correspondence, for single-phase flow, between the experimental and calculated temperatures obtained with a numerical model. In phase-change conditions, the experimental observations revealed the formation of zones. In the case of forced convection for steady-state conditions, three zones were observed and localized: a liquid-saturated zone at the bottom, a vapor zone at the top, and a phase-change zone between them. For a liquid initially at rest, these three zones were also observed during a finite time.