15. PINACLE: In-Pin Pre-Failure Molten Fuel Relocation Module

• 15.1. Overview
  • 15.1.1. Historical Background
  • 15.1.2. Physical Description of the PINACLE Model
  • 15.1.3. Interaction of PINACLE with other Models Within the SAS4A System
• 15.2. In-pin Hydrodynamic Model
  • 15.2.1. Overview of the Numerical Approach for the In-pin Fuel Motion Calculation and Description of Subroutines PN1PIN and PN2PIN
  • 15.2.2. Definition of the Generalized Smear Densities for the In-pin Hydrodynamic Calculation
  • 15.2.3. Differential Equations for the In-Pin Fuel Motion and Description of Sink and Source Terms
  • 15.2.4. Finite Difference Equations for the In-Pin Motion Model
  • 15.2.5. Treatment of the Fuel Ejection Above the Top of the Active Fuel Pin
  • 15.2.6. Time-step Determination for the Pre-Failure In-Pin Motion
• 15.3. Computer Implementation
  • 15.3.1. Detailed Logic Flow Description
  • 15.3.2. Input Parameters Relevant to PINACLE
  • 15.3.3. Output Description
• 15.4. Future Directions for Modeling Efforts.
  • 15.4.1. Annular Molten Region
  • 15.4.2. New Moving Material Components
  • 15.4.3. Inner Cladding Ablation
  • 15.4.4. Composition-Dependent Moving Mixture Properties
  • 15.4.5. Fuel Freezing in the Plenum
  • 15.4.6. Initiation of Axial Motion
  • 15.4.7. Fuel Blanket and Sodium Slug Motion
  • 15.4.8. PINACLE Termination Upon Fuel Freezing and Restart Upon Remelting
• 15.5. References
• 15.6. Nomenclature