Cell-based smoothed finite element method for simulating vortex-induced vibration of multiple bluff bodies

Abstract

Cell-based smoothed finite element method (CS-FEM) offers a new paradigm for FEM with the desirable softening effect and makes marginal modifications to existing FE codes. It is found that CS-FEM wins exceptional flexibility in integrating smoothed Galerkin weak form of field equations. This paper continues to explore the method for predicting vortex-induced vibration (VIV) of multiple rigid and flexible bodies. CS-FEM is applied to both the Navier–Stokes and multibody elastodynamic equations. A supplementary proof is presented to further interpret the irrelevance of CS-FEM to integration points. The cell-based gradient smoothing concept is also designed to accompany accurate evaluation of external fluid forces acting on multiple bluff bodies. Following an efficient mesh deformation strategy, a partitioned strong coupling algorithm is employed to couple all interacting fields under the arbitrary Lagrangian–Eulerian description. VIV of four circular cylinders and two elastic cantilevers behind obstacles is analyzed to demonstrate the enlarged applicability and good robustness of CS-FEM. A reasonable agreement is revealed between previous and present results. The main characteristics of complex flow-induced multibody oscillations are successfully captured as well.