Nuclear Technology / Volume 170 / Number 1 / April 2010 / Pages 28-39
Technical Paper / Special Issue on the 2008 International Congress on Advances in Nuclear Power Plants / Thermal Hydraulics
A condensation correlation was developed for vapor and air mixture condensation in a vertical tube based on experimental data and a mechanistic model based on heat and mass analogy model. Parametric computations were performed using a heat and mass analogy model for various operating parameters of the passive condenser system. The parameters investigated were noncondensable gas mass fraction Wbulk, mixture gas Reynolds number ReG, and Jacob number JaG. An alternating conditional expectation (ACE) regression algorithm was used to develop the condensation heat transfer correlation for the passive condenser. A total of 102600 data points was used as input to the ACE. Local condensation heat transfer correlations in terms of Nusselt number (Nucond) obtained were: Nucond = 0.08Wbulk-0.9ReG1.1exp(-42.5JaG) for turbulent flow and Nucond = 160Wbulk-0.9exp(-42.5JaG) for laminar flow. The correlations are valid for 0 Wbulk 0.5, 0 ReG 4 × 104 , 0.002 JaG 0.05. The prediction of the developed correlation agreed well with the available experimental data. The correlations are useful in predicting the heat transfer characteristics of a passive containment cooling system (PCCS) in an economic simplified boiling water reactor. These correlations apply to the three modes of PCCS operation, namely through-flow mode, complete condensation mode, and cyclic condensation and venting mode.