Whole-core depletion studies in support of fuel specification for the nextgeneration nuclear plant (NGNP) core.

9 1.0 Introduction 11 2.0 Description of NGNP Core and Fuel Elements 14 3.0 Description of Analysis Codes 18 3.1 WIMS8 and DRAGON Lattice Codes 18 3.2 REBUS-3/DIF3D Fuel Cycle Analysis Code System 21 3.3 WIMS/DIF3D/REBUS-3 Calculation Procedure 23 4.0 NGNP Depletion Sensitivity Studies with WIMS8 Lattice Code 25 4.1 Trend of Multiplication Factor with Fuel Parameters 25 4.2 Estimation of Core Cycle Length and Discharge Burnup 29 5.0 Whole-Core Model Evaluation and Studies 33 5.1 REBUS-3/DIF3D Whole-Core Model for NGNP Core 33 5.2 Verification and Sensitivity Studies of REBUS-3/DIF3D Model 36 5.3 Radial Peaking Factor Calculation with MCNP4C 44 5.4 Fuel Management Option – Single-Batch Core 47 5.5 Fuel Management Option – Two-Batch Equilibrium Core 51 5.6 Fuel Management Option – Three-Batch Equilibrium Core 61 5.7 Evaluation of Twoand Three-Batch Transitional Cores 66 5.8 Summary of Fuel Management Studies 70 6.0 Conclusions 72 References 75