[1B08-14] Boiling and Condensation

[1B12] Mechanism of CHF during Flow Boiling of Subcooled Water in a Pt Circular Tube at High Liquid Reynolds Number

(2)3 mm inner diameter and 100 mm heated length

*Koichi Hata¹, Katsuya Fukuda¹, Suguru Masuzaki² (1. Graduate School of Maritime Sciences, Kobe University , 2. National Institute for Fusion Science )

Keywords:Mechanism of Critical Heat Flux, Subcooled Flow Boiling , Platinum Circular Test Tube, High Liquid Reynolds Number , Thicknesses of Conductive Sub-layer

The subcooled boiling heat transfer and the steady state critical heat flux (CHF) in a vertical circular tube for the flow velocities (u=3.70 to 21.30 m/s) and the exponentially increasing heat input (Q=Q₀exp(t/t), t=7.41 to 26.98 s) are systematically measured by the experimental water loop. The platinum (Pt) test tube of inner diameter (d=3 mm) and heated length (L=100 mm) is used in this experiment. The thicknesses of conductive sub-layer from non-boiling regime to CHF are measured. A suggestion as to what the dominant mechanism is for the subcooled flow boiling CHF on the Pt circular tube is made at high liquid Reynolds number.