Wind-induced effects on bluff bodies in turbulent flows: Nonstationary, non-Gaussian and nonlinear features

Developments made over the past several decades in bluff body aerodynamics and aeroelasticity have enhanced our abilities to better understand and capture the effects of turbulent wind on structures. These developments had implicit assumptions of stationarity, Gaussianity and linear features while observations in storms and the attendant aerodynamic effects clearly show a departure from these tacit assumptions. In view of this, there is a need to revisit the current paradigms and to look for improved understanding concerning the nature of wind fields, the associated aerodynamics and the resulting load effects in recognition of the following emerging realities: nonstationarity/transient wind events; non-Gaussianity; nonlinearity of structural and aerodynamic origins and unsteady/transient aerodynamics. Besides, the role of turbulence in bluff body aerodynamics and aeroelasticity is emphasized and its implications are delineated. Also, one needs to take note of recent advances in analysis and identification tools, and modeling frameworks, which promise to offer better understanding of the underlying complexities associated with the aforementioned themes. This paper discusses these issues and illustrates their significance in bluff body aerodynamics and aeroelasticity from the perspective of wind effects on built infrastructure. (C) 2013 Elsevier Ltd. All rights reserved.