SEPARATE EFFECTS TESTS FOR GOTHIC CONDENSATION AND EVAPORATIVE HEAT-TRANSFER MODELS

The GOTHIC computer program, under development at NAI for EPRI, is a g eneral purpose thermal hydraulics computer program for design, licensi ng, safety and operating analysis of nuclear containments and other co nfinement buildings. The code solves a nine-equation model for three-d imensional multiphase flow with separate mass, momentum and energy equ ations for vapor, liquid and drop phases. The vapor phase can be a gas mixture of steam and non-condensing gases. The phase balance equation s are coupled by mechanistic and empirical models for interface mass, energy and momentum transfer that cover the entire flow regime from bu bbly flow to. film-drop flow. A variety of heat transfer correlations are available to model the fluid coupling to active and passive solid conductors. This paper focuses on the application of GOTHIC to two sep arate effects tests: condensation heat transfer on a vertical flat pla te with varying bulk velocity, steam concentration and temperature, an d evaporative heat transfer from a hot pool to a dry (superheated) atm osphere. Comparisons with experimental data are included for both test s. Results show the validity of two condensation heat transfer correla tions as incorporated into GOTHIC and the interfacial heat and mass tr ansfer models for the range of the experimental test conditions. Compa risons are also made for lumped vs. multidimensional modeling for buoy ancy-controlled flow with evaporative heat transfer.