Crisis of Nucleate Boiling in a Finite-Height Horizontal Layer of Liquid

This paper presents the results of measurement and calculation within an upgraded Zuber model of critical heat flux (CHF) during nucleate boiling in thin horizontal layers of liquid. The layer height was increased in regimes of developed nucleate boiling. The two-phase layer was foam with vapor columns ascending at the corners of a rectangular square lattice. In the calculations, the foam was considered as an isotropic homogeneous system. The model assumes that the diameter of the vapor columns and the critical Helmholtz instability wavelength are independent of the foam density and are determined by the length of the most dangerous Rayleigh--Taylor instability wavelength. The proposed model fits the CHF experimental data for boiling liquid and can explain the CHF decrease in solutions with addition of surfactants that increase foaming.