An analysis of the dependence on cross section geometry of galloping stability of two-dimensional bodies having either biconvex or rhomboidal cross sections. (English) Zbl 1156.76302

Alonso, Gustavo; Valero, Eusebio; Meseguer, José

Eur. J. Mech., B, Fluids 28, No. 2, 328-334 (2009).

Summary: Galloping is a well-known type of aeroelastic instability, but still difficult to predict as the relevant experimental data must first be obtained. Available information on non-rectangular cross-sections is scarce and non-systematic. The purpose of the present paper is to add new information gathered through static wind tunnel experiments. The effects of cross-sectional shape on the transverse galloping stability (according to the Glauert-Den Hartog criterion for galloping instability) of biconvex and rhomboidal cross-section bodies have been systematically analyzed. Measuring the aerodynamic coefficients and the pressure distributions along the body surfaces permits a better understanding of the galloping phenomenon and how the aerodynamic characteristics of the bodies evolve when changing parametrically the cross-section geometry from the known-case of the flat plate to the also known square or circular prisms. As a result of these investigations the potential unstable zones in the angle of attack - cross-section aspect ratio plane \((\alpha ,t/c)\) are identified.

MSC:

76-05	Experimental work for problems pertaining to fluid mechanics
76E99	Hydrodynamic stability
74F10	Fluid-solid interactions (including aero- and hydro-elasticity, porosity, etc.)

Keywords:

galloping; cross-section geometry; wind tunnel

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