Abstract
This research is focused on building up the computer models of INER Integral System Test (IIST) facility for experiment calculations by TRACE. Two experiments are included, one is the IIST Small Break Loss Of Coolant Accident (SBLOCA) the other one is Station Blackout (SBO). After doing the calculations, the results are compared to verify the TRACE code and make the experiments analysis.First, two different IIST TRACE models which include a pipe-vessel model and a 3-D vessel component model have been built. The steady state and transient calculation results show that both TRACE models have the ability to simulate the related IIST experiments. Comparing with IIST SBLOCA experiment data, the 3-D vessel component model has shown better simulation capabilities so that it has been chosen for all further thermal hydraulic studies. Second, the sensitivity studies of multipliers in choked flow model; and two correlation constants in CCFL model are made. As a result, an appropriate set of multipliers and constants can be determined. So far, a verified IIST TRACE model with 3D vessel component, and fine-tuned choked flow model and CCFL model is established for further studies on IIST experiments in the future. Third, the SBO accident of IIST TRACE model was established. Compare with the experiment data, each of the result on steady state and transient calculations are in good agreement except the primary system pressure. In order to figure out the difference, sensitivity studies on initial pressure, power curve, power delay time are discussed. Up to now, the IIST TRACE model is built up with different kinds and verified thermal hydraulic models. Applying this model to evaluate the performance of PWR could promote the understanding of the thermal hydraulic phenomena in safety analysis.