The combined influences of unsteady aerodynamics, dynamics, viscoelasticity and piezoelectricity are studied to determine their interaction and influence on sensing and structural control. Critical parameters are identified and numerical simulations are used to evaluate their sensitivities to system responses and to predict flutter conditions and control.

The hypersonic aeroelastic and aerothermoelastic problem of a double-wedge airfoil typical cross-section is studied using three different unsteady aerodynamic loads: (1) third-order piston theory, (2) Euler aerodynamics, and (3) Navier-Stokes aerodynamics. Computational aeroelastic response results are used to obtain frequency and damping characteristics, and compared with those from piston the...

Traditionally, the estimation of wind induced buffeting response and analysis of flutter instability have been conducted in the frequency domain utilizing linear approaches. These approaches are limited to linear structures in which nonlinearities in aerodynamic forces are ignored. In this study, a time domain analysis framework for predicting the flutter and buffeting responses of bridges unde...

This paper examines efficacy of tuned mass dampers ~TMD! in controlling self-excited motion resulting from negative damping. New optimal TMD parameters are suggested which provide better performance than those suggested in the literature. The dependence of TMD performance on structural damping is highlighted. The equations of motion of a combined system comprised of multiple TMDs attached to a ...

Some features of bridge aerodynamics of wind engineering are reviewed at this time, in view of the collapse of the Tacoma Narrows Bridge and also to celebrate Professor Alan G. Davenport’s 40 years of contribution to the field. Primary highlighted topics are: description of motion-dependent forces for flutter instability, presentation of gust responses caused by turbulent winds and suppression ...

Abstract This paper demonstrates the importance of assessing whirl flutter stability propeller configurations with a detailed aeroelastic model instead local pylon models. Especially growing use electric motors for propulsion in air taxis and commuter aircraft becomes an important mode instability. These often include which are powered by lightweight located at remote locations, e.g. wing tip. ...

The present work is a continuation of earlier work by the author on the energetics of flutter. It has been shown in earlier work that the energy for flutter comes from propulsion, i.e., flutter leads to increase in drag and thus the thrust has to be increased in order for the wing to maintain instability. In reality, the thrust is not increased to maintain the speed while the wing goes into flu...

Aerodynamic forces on bridges are commonly separated into static, self-excited, and buffeting force components. By delving into the relationships among force descriptors for static, self-excited, and buffeting components, novel perspectives are developed to unveil the subtle underlying complexities in modeling aerodynamic forces. Formulations for airfoil sections and those based on quasisteady ...