Revision as of 07:15, 17 December 2013

Fluid-structure interaction II

Flows Around Bodies

Underlying Flow Regime 2-14

Abstract

 The investigation of the bidirectional coupling between a fluid flow
 and a structure motion is a growing branch of research in science
 and industry. Applications of so-called fluid-structure interactions
 (FSI) are widespread. To improve coupled numerical FSI simulations,
 generic experimental benchmark studies of the fluid and the
 structure are necessary. In this work, the coupling of a
 vortex-induced periodic deformation of a flexible structure mounted
 behind a rigid cylinder and a fully turbulent water flow performed
 at a Reynolds number of \mbox{Re = $30,470$} is experimentally
 investigated with a planar particle image velocimetry (PIV) and a
 volumetric three-component velocimetry (V3V) system. To determine
 the structure displacements a multiple-point laser triangulation
 sensor is used. The three-dimensional fluid velocity results show
 shedding vortices behind the structure, which reaches the second
 swiveling mode with a frequency of about \mbox{$11.2$ Hz}
 corresponding to a Strouhal number of \mbox{St = $0.177$}. Providing
 phase-averaged flow and structure measurements precise experimental
 data for coupled computational fluid dynamics (CFD) and
 computational structure dynamics (CSD) validations are available for
 this new benchmark case denoted FSI-PfS-2a. The test case possesses
 four main advantages: (i) The geometry is rather simple; (ii)
 Kinematically, the rotation of the front cylinder is avoided; (iii)
 The boundary conditions are well defined; (iv) Nevertheless, the
 resulting flow features and structure displacements are challenging
 from the computational point of view. In addition to the flow field
 and displacement data a PIV-based force calculation method is used
 to estimate the lift and drag coefficients of the moving structure.

Contributed by: Andreas Kalmbach, Guillaume De Nayer, Michael Breuer — Helmut-Schmidt Universität Hamburg