Computational Fluid Dynamics for Reactor Design and Safety-related - PowerPoint PPT Presentation

NSE Nuclear Science & Engineering at MIT science : systems : society Computational Fluid Dynamics for Reactor Design and Safety-related Applications Emilio Baglietto emiliob@mit.edu Massachusetts web.mit.edu/newsoffice/2012/baglietto-better-reactors.htm l Institute of Technology

An Industrial/Research/Academic view Wearing multiple hats: Massachusetts Assistant Professor of Nuclear Science and  Institute of Engineering, Massachusetts Institute of Technology. Technology  Deputy Lead TH Methods Focus Area, CASL – a US Department of Energy HUB.  Nuclear Industry Sector Specialist CD-adapco.  Member of NQA-1 Software Subcommittee. Disclaimer: the following slides are intended for general discussion. They represent the personal view of the author and not that of MIT, CASL or the ASME NQA-1 Software Subcommittee. STAR Japanese Conference 2013 CFD for Reactor Design and Safety-related Applications

Contents  Nuclear Industry Competitiveness  CFD for Nuclear Reactor Design  Leveraging the research/academia efforts  Review - State of the art and current challenges  Where and why CFD  Multiscale Applications  CFD as Multi-physics platform  CFD for Safety Related Applications  The US-NRC example  Commercial Grade Dedication of Software  Experience and Challenges STAR Japanese Conference 2013 CFD for Reactor Design and Safety-related Applications

Background  2011- present A ssistant Professor of Nuclear Science and Engineering, MIT  2006-2011 Director Nuclear Application, CD-adapco  2004-2006 Research Associate, Tokyo Institute of Technology PBMR 2005 2012 2009 Emilio Baglietto - Nuclear Science & Engineering at MIT

Nuclear Industry Competitiveness (since ICONE13 – 2005) Emilio Baglietto - Nuclear Science & Engineering at MIT

CASL: The Consortium for Advanced Simulation of Light Water Reactors A DOE Energy Innovation Hub for Modeling & Simulation of Nuclear Reactors Task 1: Develop computer models that simulate nuclear power plant operations, forming a “virtual reactor” for the predictive simulation of light water reactors. Task 2: Use computer models to reduce capital and operating costs per unit of energy, …… STAR Japanese Conference 2013 6 CFD for Reactor Design and Safety-related Applications

Licensing Time / O&M Cost 1 Core and core components 2 Upper Internals 3 Steam Generator Internals 4 Steam Lines 5 PRZ components 6 Pumps and seals Flow mixing, fatigue, 7 shedding Stratification, hydrogen 8 accumulation 7 STAR Japanese Conference 2013 CFD for Reactor Design and Safety-related Applications

A “Typical” Multi -Scale Problem Full-core performance is affected by localized phenomena Model 1 Model 2 • Local T&H conditions such as pressure, velocity, cross flow magnitude can be used to address challenge problems: o GTRF o FAD o Debris flow and blockage • The design TH questions under normal operating and accident conditions such as: o Lower plenum flow anomaly o Core inlet flow mal-distribution o Pressure drop o Turbulence mixing coefficients input to channel code o Lift force o Cross flow between fuel assemblies o Bypass flow • The local low information can be used as boundary conditions for micro scale models. Emilio Baglietto - Nuclear Science & Engineering at MIT

STAR-CCM+ Platform for Multiphysics High Fidelity T-H / Neutronics / CRUD / Chemistry Modeling Petrov, V., Kendrick, B., Walter, D., Manera, A., Impact of fluid-dynamic 3D spatial effects on the prediction of crud deposition in a 4x4 PWR sub-assembly - NURETH15, 2013 Emilio Baglietto - Nuclear Science & Engineering at MIT

STAR-CCM+ Platform for Multiphysics High Fidelity T-H / Neutronics / CRUD / Chemistry Modeling Petrov, V., Kendrick, B., Walter, D., Manera- NURETH15, 2013 Emilio Baglietto - Nuclear Science & Engineering at MIT

11 Not only Fuel Related Applications Mature Applications  Fuel  Pressure Drops  Crud (CIPS/CILC)  Vibrations (GTRF)  System and BOP  Transient Mixing  Hot Leg Streaming  Thermal Striping  SG performance  Cooling Towers Interference  Fuel Cycle and Beyond Design Basis Applications  Spent fuel transportation and Storage STAR Japanese Conference 2013 CFD for Reactor Design and Safety-related Applications

boiling heat transfer void fraction DNB Multiphase CFD … better physical understanding Emilio Baglietto - Nuclear Science & Engineering at MIT

CFD for Safety-Related Design and Analysis  CFD is undoubtedly becoming a fundamental instrument in the Safety Analyst Toolbox.  CFD offers a unique opportunity for improved physical understanding   Leads to more general applicability  Reduced need for empirical calibration, which means “lower costs!”  Challenge:  Provide a path for application of CFD in Safety Analysis.  Assure that the process will capture all “critical characteristics” of the application.  Make the process “Applicable”. 13 Emilio Baglietto - Nuclear Science & Engineering at MIT

Can we apply CFD to Safety-Related Design and Analysis ? Let’s try to reformulate the question:  Is there a process that is robust, flexible, and cost effective allowing application of CFD to Safety-Related Design and Analysis.  Does the process guarantee confidence in the application of CFD. Corollary:  Is the application of CFD completely different from that of system codes..  Is it more challenging.  Is it more costly. 14 Emilio Baglietto - Nuclear Science & Engineering at MIT

Commercial Off-The-Shelf ( COTS ) CFD is apt to rely on COTS General Purpose CFD… …reasons  It has been heavily used by other industries with success.  Requires very large investment for development.  Inherits “experience” and verification practices.  Allows leveraging a very large base of users for testing.  What are the requirements for use of COTS? 15 Emilio Baglietto - Nuclear Science & Engineering at MIT

The fear of change …  Changes from NQA-1-2008 to NQA-1a-2009 Part II, Subpart 2.7 Section 302 require application of:  Part I, Requirement 7, Control of Purchased Items and Services  and Part II Subpart 2.14, Quality Assurance Requirements for Commercial Grade Items and Services  For acquisition of software that has not been previously approved under a program consistent with NQA-1 for use in its intended application.  Is it really that bad?  Is it going to make it too costly to adopt COTS?  Is adoption of COTS more challenging or more costly? 16 STAR Japanese Conference 2013 CFD for Reactor Design and Safety-related Applications

A realistic challenge  Subpart 2.14 had not really been written for software, therefore not a straightforward interpretation for an applicant.  There was a need to provide a guidance for CGD of software which would for example include. NQA-1-2012 Non-Mandatory Appendix (NMA)  Focused on dedication of Design and Analysis Computer Programs  Aligns with each of the Sections of SP 2.14 and provides information where the SP cannot be clearly interpreted as it applies to computer programs  Unique Definitions that apply to computer programs  Limits application of Like-for-Like  Omits Equivalency unless complete evaluation is possible 17 STAR Japanese Conference 2013 CFD for Reactor Design and Safety-related Applications

The process: Commercial Grade Dedication  U.S. NRC Regulatory Guide 1.28 Rev. 4, June 2010  NQA-1-2008 with NQA- 1a-2009 addendum NQA-1-2012 Non-Mandatory Appendix (NMA) EPRI 2012 - CGD Guidance for Safety- Related Design and Analysis 18 Emilio Baglietto - Nuclear Science & Engineering at MIT