SWAC-11: A Computor code for the analysis of water/steam leak from ruptured heat transfer tubes in LMFBR steam generators; Large leak sodium/water reaction analysis (No.1)

not registered; not registered; not registered; Y.W.Shi*

For the analysis of large scale sodium/water reaction accidents in LMFBR steam generators, a computor program, SWAC-11, is developed to predict water injection from double-ended guillotine rupture of heat transfer tubes. Considering the phase change in water flow, SWAC-11 can simulate the injection of subcooled water, saturated water and superheated steam. The method of numerical calculation in the code is the modified ICE (Implicit Continuous Eulerian) Method for the thermal-hydraulic transient in heat transfer tubes, while the volume-junction model is employed for the other part of water system. Simplified problems were selected to make a fundamental check of the model. Moreover, to show the applicability of the SWAC-11 to the prototypic conditions, the water/steam leak from four tube double-ended guillotione rupture in the MONJU class evaporator was calculated as an example, This code is written in JIS-FORTRAN computor language and requires 120 K bytes core memories. Typical running time for a problem with 76 cells in a tube is about 70 minutes for FACOM-230/58 to compute 5,000 time steps.