Preconditioning for low Mach number configurations

• Wave propagation velocity determines the systems Eigenvalues and the time step width
• Highly different propagation velocities of convective and acoustic waves increase the systems stiffness

  Punktstörung – nicht präkonditioniert Punktstörung - präkonditioniert . Ohne Präkonditionierung Mit Präkonditionierung

  • Deterioration of convergence behavior
  • Deterioration of solution quality
• Target: Appropriate modification of Eigenvalue
• Optimization of convergence and solution quality in regions of low velocity
• Local automatic adjustment of the preconditioning parameter using the local Mach number
• Current topics: non-reflecting boundary conditions, stability analysis and real gas formulation