Submerged Jet Impingement Boiling of Saturated Water Under Sub-Atmospheric Conditions

Abstract

An experimental study of mini-jet impingement boiling is presented for saturated conditions. Unique to this study is documentation of boiling characteristics of a submerged water jet under sub-atmospheric conditions. Data are reported at a fixed nozzle-to-surface distance that corresponds to a monotonic decrease in heat transfer coefficient for single-phase jet impingement. A mini nozzle is used in the present study with an internal diameter of 1.16 mm. Experiments are performed at three sub-atmospheric pool pressures of 0.2 bar, 0.3 bar and 0.5 bar. At each pressure, jet impingement boiling at four Reynolds numbers are characterized and compared with the pool boiling heat transfer. Enhancements in critical heat flux with increasing Re are observed for all pressures.