Analysis of the fluid-structure interaction of a semi-rigid frame

Resumo

Fluid-Structure Interaction (FSI) is characterized as a non-linear multi-physical problem and is present
in the most diverse areas of engineering, such as civil, mechanical, naval, aeronautical engineering works, among
others. In steel structures, the forces arising from the wind are actions of relevant importance and due to their
dynamic characteristics, many uncertainties exist, hindering the work of the structural engineer. Among the types
of connections used in practice, the bolt connections stand out for their simplicity and speed in the process of
assembling steel structures, both small and large. The large number of variables existing in this type of connection
- thickness of the plates involved in the connection, diameter and positioning of the bolts, etc. - however, they
make it difficult to analyze their behavior. In this work, a fluid-structure coupling problem is studied considering
low velocity flows. Due to the interdisciplinary of the theme, it is necessary to study three different subjects: the
Computational Structural Dynamics (CSD), the Computational Fluid Dynamics (CFD), and the coupling problem.
The objective of the work is to analyze the physical phenomenon of the fluid-structure interaction in a frame of
a floor with semi-rigid connections, adopting a model compatible with this situation. This model includes all the
necessary considerations for a bolt connection, specifically: contacts between plate and nut; bolt head and body;
contact between plates, as well as friction between them; restressing on the bolt. The coupled problem is solved
using Arbitrary Lagrangian-Eulerian (ALE) approach for the fluid domain, while for the solid domain a Lagrangian
approach is used. ANSYS

R software was used to model and solve the mathematical equations of the coupling
problem. This problem consists of analyzing the dynamic behavior of the structure when it is subjected to the
action of the load from random winds.