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CFX: Harmonic Analysis – GMRES (β)
• The GMRES (Generalized Minimal Residual) method is introduced as an alternative to the AMG linear
solver
- Improved convergence of Harmonic Analysis use cases, particularly at large pseudo timesteps
- 1.5 – 3x slower per coefficient loop when active
• Only activated when AMG does not reduce the residual enough
- Enable with the Expert Parameter "linear solver option = 1"
Standard AMG, timestep fraction = 1/10th GMRES, timestep fraction = 1/10th
