Boiling dryout on flat surfaces covered with bead-packed structures

摘要

Visual observations were conducted to focus on the dynamic interfacial behavior associated with dryout and rewetting during boiling on surfaces covered with porous structures made of staggered glass beads. Associated interfacial behavior was significantly affected by the bead-packed structure. Intensive wetting of the liquid replenishment protected heated surface from full dryout. Even at extremely high heat fluxes, intermittent rewetting of heated surface can also be established due to rather unsteady behavior of dry areas. Based on these unique characteristics, an introductory model was proposed to perform a theoretical analysis and explore the dryout process inside the pore structure. The theoretical results were compared with experimental data, and the present model provides a good explanation of the fundamental mechanisms and predicts the important influences of the bead-packed structure on dryout behavior.