FEA Model Updating

FEA Model Updating

By importing an FEA model and its mode shapes, or constructing an FEA model and solving for its modes prior to a modal test, this option helps you determine proper sensor and exciter locations for the test.  Following the test, you can compare the FEA & EMA mode shapes both graphically and numerically to validate your results.  Finally, selected properties of the FEA model can be updated so that its modes more closely match the EMA modal parameters.

This option includes the following features:

  • Import FEA models & mode shapes from popular FEA packages
  • Export FEA models & mode shapes in popular FEA file formats
  • Numerical comparison of FEA & EMA mode shapes using
    1. Modal Assurance Criterion (MAC)
    2. Shape difference Indicator (SDI)
  • Animated comparison of FEA & EMA mode shape pairs with highest MAC values
  • SDM-based FEA model updating.
    • Only requires FEA & EMA mode shapes, and FEA elements to be updated
    • Fast & efficient evaluation of thousands of solutions in minutes
    • Evaluates and orders FEA solutions to match
      • EMA frequencies
      • EMA mode shapes
      • EMA damping
    • FEA element properties that can be updated
      • spring stiffness, mass, linear damping
      • rods (cross sectional area)
      • bars (cross sectional area & inertias, Young’s modulus, density, poisons ratio)
      • plate elements (thickness, Young’s modulus, density, poisons ratio)
      • solid elements (Young’s modulus, density, poisons ratio)
    • FEA model creation using industry standard FEA elements The FEA element library includes;
      • springs, masses & dampers
      • rods (with axial stiffness)
      • bars (with axial, shear & bending stiffness)
      • plate elements (triangular & quadrilateral)
      • solid elements (tetrahedra, prisms and bricks)
    • FEA normal & complex mode shape solvers
      • Includes a normal mode solver for FEA models without damping, and a complex mode solver for FEA models with proportional damping.
    • EMA mode shape expansion
      • FEA mode shapes are used to add translational & rotational DOFs to EMA mode shapes
    • EMA & OMA mode shape scaling using FEA modes