NE 405/505 Reactor Systems. By Dr. Paul Turinsky Amended By Dr. J. Michael Doster

Transcription

1 NE 405/505 Reactor Systems By Dr. Paul Turinsky Amended By Dr. J. Michael Doster

2 Do not copy or redistribute without permission from Dr. Turinsky or Dr. Doster Copyright 2007 Paul J. Turinsky, 2016 J. Michael Doster

3 NE 405/505 Abbreviations List ACRS ADS ADV A/E AF AFW AOV ATWS Aux Bldg BIT BOL BOP BP BPA BTRS Bus BWR BWST CCW CF CFT CHF CHFR CPR CRA CRD CS CVCS DCBCDO DNB DNBR DP DTC EBS ECCS EFW EOL EPRI ESF FCC FP F/W or FW GCR HEx or H/X Advisory Committee on Reactor Safeguards Automatic Depressurization System Atmospheric Dump Valve Architect Engineer Availability Factor Auxiliary Feed Water (normally same as EFW) Air Operated Valve Anticipated Transient Without Scram Auxiliary Building Boron Injection Tank Beginning of Core Life Balance of Plant Burnable Poison Burnable Poison Assembly Boron Thermal Regenerative System Electric Power Distribution Circuit Boiling Water Reactor Borated Water Storage Tanks (same as RWST) Component Cooling Water Capacity Factor Core Flood Tank (same as Accumulator) Critical Heat Flux Critical Heat Flux Ratio Critical Power Ratio Control Rod Assembly Control Rod Drive Core Spray Chemical & Volume Control system Design Considerations Beyond Common Design Objectives Departure from Nuclear Boiling Departure from Nuclear Boiling Ratio Differential Pressure Doppler Temperature Coefficient Emergency Boron System Emergency Core Cooling System Emergency Feed Water (normally same as AFW) End of Core Life Electric Power Research Institute Engineered Safety Features Fuel Cycle Cost Fission Products Feed Water Gas Cooled Reactor Heat Exchanger

4 HP HPCI or HPI HPCS HVAC IC I&C ICS IFBA or IBA INPO LBP LCO LD LER LOCA LOFA LOOP LP LSSS LPCI or LPI LWR MCC MCPR MDC MDNBR MGCR MOV MTC MU MVC ND NI NRC NSSS O&M OTSG PCI PCT PID PORV PPM Pz Prz PRT PWR QA QC High Pressure High Pressure Core Injection High Pressure Core Spray Heating, Ventilation and Air Conditioning Ice Condenser Instrumentation & Control Integrated Control System Integral Fuel Burnable Absorber Institute of Nuclear Power Operations Lumped Burnable Poison Limiting Condition of Operation Letdown Flow Licensee Event Report Loss of Coolant Accident Loss of Flow Accident Loss of Offsite Power Low Pressure Limiting Safety System Setting Low Pressure Core Injection Light Water Reactor Motor Control Setting Minimum Critical Power Ratio Moderator Density Coefficient Minimum Departure from Nuclear Boiling Ratio Modular Gas Cooled Reactor Motor Operated Valve Moderator Temperature Coefficient Make Up Moderator Void Coefficient Nuclear Design Nuclear Instrumentation Nuclear Regulatory Commission Nuclear Steam Supply System Operation & Maintenance Once Through Steam Generator Pellet Clad Interaction Peak Clad Temperature Proportional + Integral + Derivative controller Pilot Operated Relief Valve Parts Per Million by weight of natural boron Pressure Pressurizer Pressurizer Relief Tank Pressurized Water Reactor Quality Assurance Quality Control

5 RC Reactor Coolant RCCA Rod Cluster Control Assembly RCIC Reactor Core Isolation Cooling RCS Reactor Coolant System RCP Reactor Coolant Pump REA Rod Ejection Accident RHRS Residual Heat Removal System RPS Reactor Protection System R/V or RV or RPV Reactor Pressure Vessel RWST Refueling Water Storage Tank (same as BWST) SAR Safety Analysis Report SDM Shut Down Margin SFRCS Safety Feed Water Rupture Control System S/G or SG Steam Generator SIS or SI/S Safety Injection System SLBA or SBA Steam Line Break Accident SOV Solenoid Operated Valve SP Suppression Pool SS Stainless Steel TBV Turbine Bypass Valve T/G or TG Turbine-Generator TGV Turbine Governor Valve TTV Turbine Throttle Valve WABA Wet Annular Burnable Absorber W/U Water to Uranium (volume, molecular or weight) ratio Zirc Zirconium

6 Introduction Design Process Definition of Design: Create a system which meets specified practical goals. Flow Diagram of a Design Problem Current Engineering Tests and Experiments Design Requirements Design Synthesis Iterate Analysis and Evaluation Specs Comparison Example: Heat Exchanger Design (1) T in P (1) m (1) (1) T ex (2) T in (2) P m(2) (2) T ex Design Requirements: Specify desired system performance & safety criteria. 1) Transfers Q (BTU/hr) amount of heat (1) (2) 2) Withstand pressure differential P P P, 3) Can mechanically tolerate pressure & temperature cycling, 4) Have materials compatible with fluids being employed, etc

7 Current Engineering Tests and Experiments Design Requirements Design Synthesis Iterate Analysis and Evaluation Specs Comparison Design Synthesis: Take all information available to derive estimate of system spec. Info: Tests & Experiments Current engineering: Systems already operational and/or designed. Estimate System Specs: Perform parametric and preliminary design calculations Example: Specs for heat exchanger: 1) Basic Type (once-through/counter-flow/straight tube-shell design). 2) Length, I.D. & O.D of tubes & shell. 3) Material composition of tubes & shell. 4) Etc. Analysis & Evaluation: From estimated specs, calculate system output characteristics & design requirement information. Conducted by calculations usually via computer codes & validated against experiments. Example: Output characteristics of heat exchanger: 1) Energy transfer rate. 2) Temperature distribution of fluids, tubes & shell. 3) Thermal & pressure induced material deformation. 4) Crud deposition on tube walls effect on heat transfer performance. 5) Tube and shell side pressure drop 6) Etc.

8 Comparison: Contrast design requirements & actual performance & use as further info in Design Synthesis step. Specs: Once Design Requirements are satisfied, obtain detailed specs of system. Many times Design Requirements are not specific enough to conclude unique design, so Design Requirements are added during the design process. Design-Parameter Interplay Many parameters must be set to obtain design specs. Since parameters are highly interrelated, changing one parameter may require several other parameters to be changed to satisfy Design Requirement. Example: Changing tubing material to be more inert to fluid has implications on deformation and thermal performance. This may require different tube I.D., O.D. & length.

9 Non-technical Uniqueness of the Nuclear Power Plant Design Process 1) Auditable by customers & NRC. 2) Design organizational structure must conform to NRC requirements. 3) The public s right to know with safety related matters. Nuclear Power Plant Design Fundamentals Design Requirements: (some of many) (Not Unique to Nuclear Power) 1) Electric Power Output (MWe) 2) Availability Factor (Target of 95% ) 3) Maximum Thermal Efficiency to minimize: a. Environmental impact b. Power Cost. 4) Low power cost a. Capitol Cost ( 75% of total) b. Fuel cost ( 10% of total) c. Operation & Maintenance cost ( 15% of total) 5) Load follow capability (change power level rapidly) 6) Safety 7) Pollution Control (EPA/State & Local Governments) (Unique to Nuclear Power) 8) Licensability (ACRS/NRC/EPA/State & Local Governments) 9) Cycle Length (Refuel usually 1 ½ to 2 years)

10 System Overviews Basic Nuclear Power Plant System Layout: To satisfy the Design Requirements, several different systems have evolved: Pressurized Water Reactors (PWR) Boiling Water Reactors (BWR) Gas Cooled Reactors (GCR) Sodium Fast Reactors (SFR). Our attention will be focused principally on the PWR & BWR systems, collectively referred to as Light Water Reactors (LWR). All nuclear reactor plants are designed using the same concepts that fossil fired power plants employ, except that nuclear fission replaces exothermic chemical reactors as the energy source. Typical simplified flow diagrams for a PWR & BWR are shown in the following figures.

11 Simplified Diagram of a Four-Loop NSSS

12 Reactor Vessel and Internals

13 Indirect Cycle PWR

14 Direct Cycle BWR

15 Steam and Recirculation Flow Paths of the GE BWR

16 Typical GE Boiling Water Reactor

17 Advanced BWR

18 Industry Subdivisions and Participants Subdivision of Responsibilities in Design Process: Since a nuclear power plant involves many different organizations in the design and construction stages, it was necessary to subdivide the plant in a fashion to allow: 1) Meaningful information flow interfaces to be established 2) Assignment of responsibility What have evolved are the following two large subdivisions: 1) Nuclear Steam Supply System (NSSS) a. Reactor Vessel & Components: Pressure Vessel Fuel Assemblies Control Rods & Drives Baffle Thermal Shield Upper & Lower Core Support Plates Steam Separators (BWR), Etc. b. Reactor Coolant System (RCS) Components: Coolant Pumps Pressurizer Steam Generators (PWR) Chemical & Volume Control Systems (CVCS) Safety Components Reactor Protection System (RPS) Emergency Core Cooling System (ECCS) Emergency Boration System (EBS) Residual Heat Removal System (RHRS) 2) Balance of Plant (BOP): a. Containment, Auxiliary Building, Rad Waste Building, etc. b. Steam Components: Piping, Condenser, Turbine/generator c. Feedwater System d. Component Cooling System e. Electrical Systems f. Instrument Air System g. Etc.

19 Participants: 1) Utilities: Desires: Low Capital investment, short construction time, low energy costs, reliability, safety, low environmental impact, licensability, and long-term fuel resources. Role: Defines system gross requirements such as power rating (MWe), load following capability, availability factor (AF), evaluate bids, project management and license holder, operations and maintenance (O&M) 2) NSSS Vendors: Role: design, fabricate, and warrants NSSS components Examples: GEH, Westinghouse & AREVA 3) Turbo-Generator Vendors: Examples: GE, Siemens 4) Architectural Engineering (A/E): Role: design entire plant, how to assemble components and build structures; also evaluates bids on NSSS (sometimes) Examples: Bechtel and Shaw 5) Contractors Role: constructs buildings and assembles equipment Examples: A/E s, Daniels, etc. and Utilities Condensation of Responsibility: In some instances, one organization assumes multiple roles, e.g : Duke and TVA : Turn-Key; GE, Westinghouse in the past