Investigation and Selection of Entrainment-Deposition Correlations for the Development of SPACE code

Since 1970s, various safety codes have been developed to predict the thermal-hydraulic phenomena in nuclear power plant and many studies have been performed to improve the prediction performance and accuracy. One of the most important issues to develop and to improve the safety codes is the droplet entrainment and deposition (En-Dep) behavior in the safety analysis and design of a nuclear power plant. Until now, most of the thermal-hydraulic system code, such as TRAC and RELAP5, have been developed based on the liquid phase deal with a single set of average equation and with the averaged liquid phase equation (a two-field model), so that the behavior of a droplet cannot be described accurately. On the other hand, COBRA-TF provides a two-fluid, three-field representation of two-phase flow in which continuous liquid and entrained liquid drops and described separately. At the present time, SPACE (Safety and Performance Analysis CodE) has been being developed in Korea based on a three-field model for predictions and analyses of general thermal-hydraulic phenomena in a nuclear power plant. In this paper, investigation and selection of En-Dep correlations are performed to develop an En-Dep module in SPACE code