TAILIEUCHUNG - Multi modes coupling galloping of slender structures

The paper presents a general theoretical framework for galloping analysis of slender structures, taking into account the coupling among modes, the modes shapes, and the variation along the structure of mass per unit length and mean wind velocity. | Journal of Science Ho Chi Minh City Open University - VOL. 20 4 2016 - December 2016 41 MULTI MODES COUPLING GALLOPING OF SLENDER STRUCTURES NGUYEN HUY CUNG Industrial University of Ho Chi Minh City Vietnam - Email nguyenhuycung@ DO CAO PHAN Industrial University of Ho Chi Minh City Vietnam - Email docaophan@ LE VAN HUNG Industrial University of Ho Chi Minh City Vietnam - Email hungvanle@ HUYNH LE EM Industrial University of Ho Chi Minh City Vietnam - Email huynhleem@ Received September 09 2016 Revised November 03 2016 Accepted December 06 2016 ABSTRACT The paper presents a general theoretical framework for galloping analysis of slender structures taking into account the coupling among modes the modes shapes and the variation along the structure of mass per unit length and mean wind velocity. The theory is then applied to a real structure. In the galloping analysis aerodynamic coefficients are obtained from wind tunnel tests. The results of the analysis show crucial points different from conventional analysis. Keywords Aeroelasticity Aerodynamics wind-induced instability wind tunnel tests. 1. Introduction Aeroelasticity is the study of the interaction among aerodynamic forces and structural motion. Phenomenon which is characterized by rapid increase of the structural response due to the aeroelastic forces is referred to as aeroelastic instability phenomenon. Aeroelastic stability in the quasi-steady range has been analysed since over 90 years ago but not all aeroelastic phenomena are entirely understood. The very first study the aeroelastic instability in quasi-steady range referred to galloping was introduced by Glauert 1919 and Den Hartog 1932 with a criterion for the critical condition for one degree of freedom 1DOF transversal galloping. According to that the galloping occurs in the crosswind direction when the aerodynamic damping is negative. This criterion is referred to as Glauert-Den Hartog s criterion which has .

• Kiến trúc - Xây dựng
• Wind induced instability
• Wind tunnel tests
• General theoretical framework
• Slender structures
• Modes shapes