Partitioned iterative and dynamic subgrid-scale methods for freely vibrating square-section structures at subcritical Reynolds number

In this paper, we present a partitioned iterative and a dynamic subgrid-scale (SGS) scheme to simulate flow-induced vibration of freely vibrating structures in a turbulent flow. The hybrid partitioned scheme relies on the combined interface boundary conditions and non-linear interface force corrections to stabilize the variational coupled system based on the filtered Navier-Stokes and rigid-body dynamics. The iterative interface corrections provide the force equilibrium with arbitrary accuracy while maintaining the velocity continuity condition along the fluid-structure interface. We show that our second-order scheme is stable for both VIV and galloping instabilities found in a freely vibrating square cylinder with strong added-mass effects for mass ratio (solid mass to displaced fluid mass) ranging from m* is an element of [0.1, 10]. We validate the dynamic subgrid-scale scheme for the benchmark problem of the three-dimensional (3D) flow past a square cylinder at moderate Reynolds number. We assess the response characteristics of freely vibrating square cylinder with the recent experimental data at zero and 45 incidence. We demonstrate the SGS-based large-eddy simulation solver for full-scale multicolumn semi-submersible floater subjected to flow-induced motions at subcritical Reynolds number Re = 20, 000 based on the diameter of column section. The transverse amplitude and the Strouhal number of the floater are validated against the experimental data. (C) 2016 Elsevier Ltd. All rights reserved.