A mathematical model of the pool boiling nucleation site density in terms of the surface characteristics

Abstract

Dependence of active nucleation site density on boiling surface conditions are developed in a form of N = N · φ( β) · φ( r). The average cavity density N is obtained from the measurement of the boiling surface. The distribution functions φ( β) and φ( r) are of the form φ(β) = ∫ 0 θ 2 f(β) dβ, φ(r) = ∫ r min r max f(r) dr . The probability density function of the cavity mouth radius f( r) and the cone angle f( β) are obtained through a statistical treatment based on the measured cavities by a scanning electron microscope and a differential interference contrast microscope. The limits of integrations are given by the entrapment mechanism. The agreement between the result of the analysis and experimental data is good.