A new method is proposed for the identification of global nonlinear models of aircraft non-dimensional force and moment coefficients. The method is based on a recent type of multivariate spline, the multivariate simplex spline, which can accurately approximate very large, scattered nonlinear datasets in any number of dimensions. The new identification method is used to identify a global nonline...

ABSTRACT: An approximate approach for the frequencyand time-domain aeroelastic analysis of bridge decks is presented. The aerodynamic transfer functions are approximated as a linear function with the coefficients determined through minimization of the weighted error between the exact and approximated transfer function. The weighting function in optimization is introduced for the improved approx...

This paper presents a time domain analysis framework for predicting nonlinear response of long-span bridges under turbulent winds. The nonlinear unsteady aerodynamic forces are modeled based on static force coefficients, flutter derivatives, admittance functions, and their spanwise correlations at varying angles of incidence. This analysis framework incorporates frequency dependent parameters o...

Flow separation at the vehicle’s rear end is the major cause of an aerodynamic drag in a car. In order to delay the flow separation at the rear, bump-shaped vortex generators at the roof end of a car are tested in this paper for two different types of car models Sedan and Hatchback. The aerodynamic analysis is carried out using GAMBIT and FLUENT for Sedan and Hatchback models. Vortex Generators...

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...

determining characteristics and behavior of fluid flow and obtaining the aerodynamic coefficients are important and considerable tasks in investigation of flow over the bodies. in this research, leading edge radius effects on the flow behavior over a delta wing with a sweep angle of 50 degree at different reynolds numbers between 0.5×106 and 2.5×106 are investigated numerically. three different...

Gliding is an efficient form of travel found in every major group of terrestrial vertebrates. Gliding is often modelled in equilibrium, where aerodynamic forces exactly balance body weight resulting in constant velocity. Although the equilibrium model is relevant for long-distance gliding, such as soaring by birds, it may not be realistic for shorter distances between trees. To understand the a...

Wilson's storm petrel (Oceanites oceanicus) characteristically feeds by ' hovering' over the water surface, but its technique for this is unlike that of other flying vertebrates. The kinematics and aerodynamics of this ' hovering' flight were investigated to determine the possible sources of lift; various nonaerodynamic sources of lift were discounted. It is suggested that the storm petrel soar...

The aerodynamic behavior of a 48’ yacht rig 3D scale model was characterized by means of wind tunnel tests. The experimental program, performed in the Politecnico di Milano Twisted Flow Wind Tunnel, allowed the aerodynamic forces to be characterized using forced motion tests and the aeroelastic behavior of the sail plan to be studied. Preliminary results are presented with reference to the typi...