Some Features of Subcooled Dielectric Refrigerant R113 Boiling

The article presents the specific features of nucleate boiling of subcooled dielectric Freon R113 compared to water, revealed by generalizing existing and newly obtained experimental data. The experiments were carried out at atmospheric pressure in the ranges of subcooling to the saturation temperature Δt_sub = 28–45°С and mass velocity ρw = 0–1500 kg/(m² s). The main method for visualizing and registration flow characteristics was high-speed video filming with a frame rate of up to 50 kHz. The study revealed the absence of mechanisms underlying deactivation of nucleation sites and heat removal from the surface of a bubble observed during boiling of subcooled water at its growth stage via nonstationary thermal conductivity with a moving phase boundary. More favorable conditions for vapor phase accumulation in the core of a flow compared to water are demonstrated.