Studies on pool boiling heat transfer. 1st. Report. Proposed physical model for kutateladze-zuber correlation of CHF.

Abstract

The Kutateladze correlation (1948) is widely used to predict critical heat flux (CHF) for various geometries of heated surfaces. A reasonable model which gives the correlation is not yet known. In this paper, the physical implications of the correlation are discussed and a model giving the correlation has been proposed. This model is derived on the basis of the measured diameters of various bubbles and the photographic records of boiling in higher pressures by Semeria (1963). In the model, a macrolayer δ1 is formed by the coalescence of the secondary bubbles formed by the primary bubbles. Tertiary bubbles formed by the secondary bubbles determine the frequency f of the macrolayer formation. The CHF is determined by the following relation: qCHF=δ1ρlHfgf, where ρl is the density of liquid and Hfg is the latent heat of evaporation. One of the formulations of the model gives the Kutateladze or Zuber correlation.