r4.07.04 Fluid-structure coupling for tubular structures and coaxial shells

Summary:

This document describes the various fluid-structure coupling models available using operator CALC_FLUI_STRU. These models make it possible to simulate fluid-elastic coupling forces in the following configurations:

• bundles of tubes under transverse flow (mainly for GV tubes),

• control rod passage/housing plate (exclusively for control clusters),

• coaxial cylindrical shells under annular flow (tank space/core envelope), … ),

• bundles of tubes under axial flow (fuel assemblies,…).

For each configuration, the fluid-elastic forces model is first presented. The resolution of the modal problem is then described. The resolution methods used integrate the specificities of the various fluid-elastic force models.

• 1. General presentation
  • 1.1. Reminders
  • 1.2. Modeling
• 2. Fluid-elastic excitation acting on tube bundles under transverse flow (essentially for GV tubes)
  • 2.1. Description of the studied configuration
  • 2.2. Calculation steps
  • 2.3. Expression of the fluid-elastic force transfer matrix
  • 2.4. Solving the modal problem under flow
  • 2.5. Connors method
• 3. Fluid-elastic excitation acting on the control rod at the level of the housing plate (exclusively for control clusters)
  • 3.1. Description of the studied configuration
  • 3.2. Calculation steps
  • 3.3. Representation of fluid-elastic excitation
  • 3.4. Projection on a modal basis and expression of the terms of the fluid-elastic force transfer matrix
  • 3.5. Solving the modal problem under flow
• 4. Fluid-elastic excitation acting on two coaxial cylindrical shells under annular flow (example: tank space/core envelope)
  • 4.1. Description of the studied configuration
  • 4.2. Calculation steps
  • 4.3. Solving the unsteady fluid problem
  • 4.4. Solving the modal problem under flow
• 5. Axial flow (example: fuel assemblies)
  • 5.1. Description of the studied configuration
  • 5.2. Calculation steps
  • 5.3. Solving the unsteady fluid problem
  • 5.4. Solving the modal problem under flow
  • 5.5. Taking into account the presence of the tube bundle grids
  • 5.6. Taking into account the amortization of fluid at rest
• 6. Bibliography
• 7. Description of document versions