[2E01-04] Boiling

[2E04] CHF and Liquid-Vapor Structure Near Heating Surface in Flow Boiling on a Vertical Surface

*Takashi Furuhashi¹, Hiroto Sakashita¹ (1. Hokkaido Univ.)

Keywords:Critical heat flux, Flow boiling, Liquid layer thickness, Void fraction, Conductance probe

Critical heat flux (CHF) for flow boiling is categorized into two types, dryout and DNB. For dryout CHF, it is already found that it occurs when the liquid film adjacent to the heated wall dries out. On the other hand, the trigger mechanism for DNB CHF has not been fully established. In this study, the liquid-vapor behaviors near the heating surface were measured using a conductance probe. Through these measurements, the existence of liquid film between the vapor and heating surface was confirmed. In addition, it was clarified that the flow velocity has little effect on the liquid layer thickness, and large effect on the vapor mass passage period.