Theory Manual

This section describes the theoretical background of Kynema such as formulation of elements, constraints, and other relevant topics.

• Formulation overview
• Time integration: Generalized-Alpha
• Member library
  • Rigid body
  • Geometrically nonlinear spring
  • Geometrically Exact Beams
    • Geometrically exact beam theory
    • Legendre spectral finite elements
    • Notes on quadrature
    • Beam reference lines and reference configuration
• Model configurations
  • Heavy top constrained-rigid-body example
  • Rigid body with three springs
  • Model bodies and constraints for a HAWT
    • Constraints
    • Constraint Gradient
    • Additional iteration matrix terms due to constraints
    • Data layout
• Coupling for fluid-structure-interaction
  • Overview
  • Data initialization and transfer between solvers
  • Fluid-structure spatial mapping
  • Coupling in time
    • Overview
    • FSI Algorithm: Actuator-line CFD (AMR-Wind)
    • FSI Algorithm: geometry-resolved CFD (Nalu-Wind)
  • Motion transfer: Structure to fluid nodes
  • Force and Moment transfer: Fluid to structure
• Blade-element aerodynamics solver
  • Initialization
  • Force calculations based on blade-element polars