The aeroelastic behavior of slender structures such as long-span cable-supported bridges is essential to be studied as part of their design as they can develop significant vibrations when exposed to atmospheric wind flow. The trends for increase in the flexibility and reduction of mass of structures make such problems more prominent and the analysis more challenging, thus amplifying the need for accurate, robust and efficient prediction models.
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An in-house flow solver based on Vortex particle Method (VPM) is extended for 2D and pseudo-3D FSI simulation of thin-walled systems. A structural solver based on a corotational finite element formulation is coupled with 2D VPM to account the geometrically nonlinear effects accurately. This model is extended further to perform aero-electromechanical coupled simulation for analyzing the performance of different cantilever energy harvesters. Furthermore, the existing pseudo-3D multi-slice model is extended to simulate the FSI simulation of thin surface type systems such as cantilever roofs and cooling towers.
Several research loci are considered as a part of this project, including: (i) a categorical modeling approach for aerodynamic model evaluation; (ii) turbulent Pseudo-3D vortex method for buffeting and flutter analyses of bridges; (iii) a synergistic comparison framework for CFD and semi-analytical models; (iv) comparison metrics for time-histories, tailored to identify and quantify features certain features of the time-dependent aeroelastic response and forces; (v) a method for determination of the complex form of the aerodynamic admittance by simulating deterministic gusts.
Modern models and methods are arising to tackle the increasing need to address non-linearity in slender structures under wind flows. These, however, do require validation. The best way to achieve this is through the implementation of experimental procedures that would allow for the substantiation of the proposed approach.
Flexible, slender and tall structures, such as high-rise buildings, bridges or chimneys are sensitive to dynamic wind excitations, therefore damages or fatigue may occur. For many of these structures, the provision of additional damping is the only robust and pratical method to control dynamics problems. Liquid dampers represent a research area with increased applicability in structures due to their low maintenance costs and efficiency in use. The research work will involve numerical coupling of liquid tanks in wind-structure response analyses.
With the increasing spans and complex deck shapes, aerodynamic nonlinearity becomes a crucial concern in the design of long-span bridges. Conventional bridge aerodynamic models consider the force induced by the free-stream turbulence and deck motion to be independent. The models do not account for the two crucial interaction aspects closely tied to aerodynamic nonlinear behavior: the effect of large-scale sinusoidal vertical gusts on the shear layer of a moving body and the nonlinear dependence of the aerodynamic forces on the effective angle of attack. It is vital to study the wind-induced vibration problem in a turbulent environment synergistically to capture these effects.
