Author:

Keywords:

Science & Technology, Technology, Acoustics, Engineering, Mechanical, Engineering, COMPUTED FLOW-FIELD, FORMULATION, CYLINDER, LOCATION

Abstract:

Circular cylindrical shells, like silos, are perceptible to wind induced ovalling oscillations, an aeroelastic phenomenon, where the cross section deforms as a shell without bending deformation of the longitudinal axis of symmetry. A fluid-structure interaction analysis aims to predict the ovalling onset flow velocity. An approximate analysis will be performed by reducing the structure, using the finite strip method, to two dimensions and by coupling it with a two dimensional flow. First, the mode shapes and eigenfrequencies of a three-dimensional finite element and a finite strip model of the silo structure are compared. A transient 2D turbulent air flow around a single silo at a Reynolds number of 1.24 ×107 is computed using the SST turbulence model and the results are compared with the pressure coefficients in Eurocode 1 and with experimental data. Unsteady simulations are performed for the flow around a group of 8 by 5 silos. The group configuration drastically changes the time-averaged pressure distribution around the silos. The fluid and the structure are sequentially coupled, using interfield iterations to fulfill equilibrium and conservation of energy on the interface. The coupling procedure is validated by means of available experimental results of wind tunnel tests. Preliminary results of a transient fluid-structure interaction calculation at a wind speed of 7 m/s are reviewed. © (2006) by the Katholieke Universiteit Leuven Department of Mechanical Engineering All rights reserved.