1. UNIVERSITÀ DI PISA Gruppo Ricerca Nucleare S. Piero a Grado Recent Applications of RELAP5-3D at GRNSPG N.Muellner 2011 RELAP5 International User’s Group Seminar And Meeting Salt Lake City, UT, July 25-28, 2011

2. Gruppo Ricerca Nucleare S. Piero a Grado 2 RELAP5 International User's Group Seminar and Meeting, Salt Lake City, UT, July 25-28, 2011 CONTENTS  Introduction  Fast Data Access (HDF5 file format)  3DS Viewer  Conclusions

3. Gruppo Ricerca Nucleare S. Piero a Grado 3 Introduction  CNA2 – Chapter 15 FSAR – one of the main projects of GRNSPG 2007-2010  Relap5-3D main tool for analysis  Applications (incomplete list)  Three different nodalizations for RCS  3D Neutronics  Coupling to code modelling I&C

4. Gruppo Ricerca Nucleare S. Piero a Grado 4 The Atucha-2 NPP 2 LOOPS 1 MCP, 1 UT SG each 1 PRZ 2160 MWth 1958 + 203 (nom. mod. T), or 2001 + 160 (max mod T) + 14 from MCP 451 separated FC

5. Gruppo Ricerca Nucleare S. Piero a Grado 5 The Atucha-2 NPP

6. Gruppo Ricerca Nucleare S. Piero a Grado 6 83 NPP Scenarios THE BEPU PROCESS THE POSTULATED INITIATING EVENTS (PIE)

7. Gruppo Ricerca Nucleare S. Piero a Grado 7 Introduction RELAP5-3D – Calculation of Temperatures, Pressures, Mass flows etc Multiple Timesteps inside “Control-timestep” DYNETZ – calculation of Signals from Control System Ovars: Temperatures Pressures Massflows Ivars: Valve postions Pumps on/off PRZ Heaters & Spray DRIVER-PROGRAM

8. Gruppo Ricerca Nucleare S. Piero a Grado 8 Introduction  Results 2007-2011, apart from FSAR Chapter 15 - data of several TB  2011 Activities –  Qualification  Consolidate data bases  Visualization

9. Gruppo Ricerca Nucleare S. Piero a Grado 9 Fast Data Access & Quality Control  Need to organize data  HDF5 data format chosen  Open format supported by plotting software such as Tecplot  User can determine data structure  Possibility to save all data which are part of one calculation in one file  Controls may be imposed when file is created

10. Gruppo Ricerca Nucleare S. Piero a Grado 10 Fast Data Access & Quality Control  HDF5 ideal for large data sets  B-Tree (generalization of a binary search tree)  Chunking may be enabled (file sensitive to size of chunks)  At the moment, we could reach a maximum time of access of 1s (room for improvement)  HDF5 is used by (among others)  NASA (climate and geographic data)  DOE (Advanced Simulation and Computing Program)  Boeing  Open libraries available for reading/creating HDF5 files

11. Gruppo Ricerca Nucleare S. Piero a Grado 11 3D - Viewer  Our ProEngineer Technical Drawings of NPP can be exported into.3ds file format (format by Autodesk)  3ds file format can be read by open libraries, and is tuned to be displayed with OpenGL  OpenGL visualization

12. Gruppo Ricerca Nucleare S. Piero a Grado 12 3D Viewer  Putting together  Fast data access HDF5  Our technical 3D drawings  3ds- OpenGL Libraries  3D Visualization of Relap5-3D results

13. Gruppo Ricerca Nucleare S. Piero a Grado 13 Conclusions  Fast data access - HDF5  Fast access to large data files  Common standard, supported by commercial plotting – packages  Possibility to define controls on data set generation  3D Viewer  Fast 3D Visualization using existing drawings  Use of open libraries, independent from OS