Pool Boiling Critical Heat Fluxes in Subcooled FC-72

摘要

The steady-state and transient critical heat fluxes (CHFs) due to increasing heat inputs were measured in wide ranges of liquid subcoolings and pressures in a pool of FC-72. Measurements were taken on 1.0 mm diameter of platinum and gold horizontal cylinder heaters. The increasing rate of steady-state CHFs for liquid subcooling is lower than the hydrodynamic instability (HI) model at high subcooling condition, and it was suggested due to the heterogeneous spontaneous nucleation (HSN). Transient CHFs on semi-direct and direct transitions from non-boiling regime to film boiling, exist predominantly during short periods. Those transition processes were assumed due to the explosive-like HSN in originally flooded cavities on cylinder surface. Each of the steady-state and transient CHFs that were obtained from both heaters in various liquid subcoolings and pressures, generally well agree each other.