Meaning
Numerical simulation techniques for fluid-structure interaction rely on iterative algorithms to maintain grid quality during boundary movement. Engineers use dynamic mesh relaxation to adjust the positions of internal nodes without altering the connectivity of the underlying mesh.
Convergence Rate
Algorithmic stability improves when the smoothing algorithm operates within optimal deformation limits. A high convergence rate ensures that the solver reaches a resolved state in fewer iterations during transient calculations. When deformation rates exceed the capacity of the relaxation algorithm, the mesh becomes tangled and terminates the run.
Fast deformation forces the solver to apply aggressive smoothing coefficients, which often reduces the accuracy of the localized flow gradients.
Computational Cost
Additional memory allocation and CPU cycles are required when updating node positions at each time step. Although dynamic mesh relaxation prevents grid degeneration, the iterative recalculation of coordinates consumes substantial processing resources. Simpler mesh smoothing techniques run faster but fail under severe shear.
Boundary Condition
The technique stops applying when the boundary displacement exceeds the initial cell height. This threshold represents the absolute limit where node shifting can no longer prevent cell inversion or negative volumes. The boundary condition dictates the maximum allowable time step size for the entire transient analysis.
