1 / 12

OECD/NRC BWR Peach Bottom-2 Turbine Trip Benchmark – 2 nd Workshop, Villigen,October 2001

PAUL SCHERRER INSTITUT. PB2 TTRIP Phase 2 Coupled 3D Kinetics/Core Thermal-Hydraulic BC Analysis with CORETRAN. H. Ferroukhi, W. Barten, P.Coddington. OECD/NRC BWR Peach Bottom-2 Turbine Trip Benchmark – 2 nd Workshop, Villigen,October 2001 . PAUL SCHERRER INSTITUT. CONTENTS.

paul2
Download Presentation

OECD/NRC BWR Peach Bottom-2 Turbine Trip Benchmark – 2 nd Workshop, Villigen,October 2001

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. PAUL SCHERRER INSTITUT PB2 TTRIP Phase 2 Coupled 3D Kinetics/Core Thermal-Hydraulic BC Analysis with CORETRAN H. Ferroukhi, W. Barten, P.Coddington OECD/NRC BWR Peach Bottom-2 Turbine Trip Benchmark – 2nd Workshop, Villigen,October 2001

  2. PAUL SCHERRER INSTITUT CONTENTS • CORETRAN and RETRAN-3D at PSI • PB2 TTRIP Phase 2: 3-D Kinetics with Core T/H Boundary Conditions • Steady-State Results • Transient Results • Summary

  3. CORETRAN • 2 Group, 3-D • Core Static Depletion and Transients • Neutronics • ARROTTA (ANM) • ANM-NEM /CMFD • Thermal-Hydraulics • VIPRE-02 • Stand Alone Sub- Channel Analyses • 3 Eq. HEM to 6 Eq. • RETRAN-3D • 2 Group, 3-D • Core and Plant System Transients • Neutronics • ARROTTA (ANM) • ANM-NEM /CMFD • RETRAN Thermal-Hydraulics • 3 Eq., 4 Eq., 5 Eq. PAUL SCHERRER INSTITUT CORETRAN and RETRAN-3D at PSI • PSI transient code environment with CORETRAN / RETRAN-3D

  4. PAUL SCHERRER INSTITUT PB-2 Phase 2: Objectives at PSI • ANALYSIS WITH CORETRAN: Coupled 3-D Kinetics/Core Thermal-Hydraulic BC Model • Steady-state at both TT2 Conditions and HZP • Transient Analysis: • Analysis performed and submitted • ANALYSIS WITH RETRAN-3D: Coupled 3-D Kinetics/Core Thermal-Hydraulic BC Model • RETRAN-3D Model needs to be set-up for Phase 3 but can also be used for Phase 2 • Model set-up based on CORETRAN • Lumped Model necessary in RETRAN-3D (Homogenized T/H Feedback Variables !) • Steady-State analysis at HZP to verify consistency in Neutronic Solution CORETRAN-RETRAN-3D • Steady-State and Transient Analysis at TT2 Conditions with 33-T/H Lumped Model • Assess differences between CORETRAN and RETRAN-3D • Influence of T/H solution and void model • Influence of T/H feedback homogenization • Analysis with RETRAN: 1-D Kinetics • Additional exercise if time available • Valuable to assess differences 1-D/3-D

  5. PAUL SCHERRER INSTITUT PB2 Phase 2: CORETRAN Model of PB2 • ANM Neutronic Algorithm (ARROTTA) • 6 Equation 2 Fluid T/H Model (VIPRE-02) • Full Core Representation • 1x1 Neutronic and T/H Radial Mesh • Bypass = 1 Additional T/H Channel • No Bypass Void • Detector Model • X-S model modified • X-S tables read directly • Use of provided X-S interpolation routine • Xenon densities read as Restart file • No Decay Heat Model

  6. PAUL SCHERRER INSTITUT PB2 Phase 2: CORETRAN Steady-State Results

  7. PAUL SCHERRER INSTITUT Note on Spacer Void Model • Spacer Void Model (SVM) available in SIMULATE-3 to treat void accumulation at Spacer Grids • PSI Experience with Swiss BWRs shows very good agreement with TIP with the SVM • Assessment CORETRAN/SIMULATE performed at PSI for Swiss LWRs show that the SVM has a • Strong impact on the axial power shape in the boiling zone • Strong impact on the core reactivity (more negative void coefficient in boiling zone)

  8. PAUL SCHERRER INSTITUT PB2 Phase 2: CORETRAN Transient Results • Analysis 1: Boundary Condition = Total Core Flow versus Time • 6 Eq. + NBC • FIBWR Flow Split Model in quasi-static mode • Pressure-Flow Convergence Problems Power and LPRM Core Flow Pressure

  9. PAUL SCHERRER INSTITUT PB2 Phase 2: CORETRAN Transient Results • Analysis 2: Boundary Condition = (33 T-H Channels) + ( Bypass Channel) Flow versus Time • No FIBWR Model No Bypass Correction (Nominal) With Bypass Correction (BC1)

  10. PAUL SCHERRER INSTITUT PB2 Phase 2: CORETRAN Transient Results • Sensitivity Studies: Boundary Condition = (33 T-H Channels) + ( Bypass Channel) Flow versus Time • Time Step Size • SCRAM Signal Time Step Size SCRAM Signal

  11. PAUL SCHERRER INSTITUT PB2 Phase 2: Summary • CORETRAN Model for PB-2 Exercise 2 Set-Up • Steady-State Analysis at TT2 Conditions • Good agreement with PB1 Edit • Axial Power Shape (Caution on spacer void) • Core Average Void Fraction, Average Exit Quality, Core Pressure Drop • Very High K-eff • Transient Results • Analysis with total ore flow BC + FIBWR flow split UNAPPLICABLE • Analysis with 33-TH Channel flow BC • No Bypass Correction gives slight under prediction of power peak (Nominal Case Submitted) • Later analysis with Bypass Correction shows better agreement with measurements • Sensitivity Analysis • Large sensitivity on time-step size • Small Time-Step size of 1ms selected • Choice of SCRAM on 95% power instead of defined t=0.63 s seems more adequate • but leads to earlier and lower power peak magnitude • Next Step is to perform similar analysis with RETRAN-3D before Phase 3

  12. PAUL SCHERRER INSTITUT PAUL SCHERRER INSTITUT PB2 Phase 2: CORETRAN Bypass Model • CORETRAN PB2 Bypass Model • Defined Leakage Paths • Core Support Plate • Control Rod Drive Housing • Assembly Lateral Leakage • Path a: Through Lower Tie Plate Holes (9 in FIBWR) • Path b:between Channel Box and Lower Tie Plate (8 in FIBWR) • Path c:Water Rods • All Paths to ONE SINGLE BYPASS T/H CHANNEL • Bypass Geometry • Assumed Core Shroud Diameter • D_CS = 5.6 m (220.47 in) • Based on EPRI Report NP-563 • Assumed Assembly Outer Pitch • P_OUT = 0.1365 m (5.37 in) • Bypass Flow Area = 7.5 m2 (11570 in2) 1 FIBWR Model All Leakage Paths defined by Flow-Pressure Drop Correlations

More Related