Vibrations of Chimneys under the Action of the Wind (original) (raw)

Vibrations of chimneys under the wind act ion occur in-line with the wind as forced, random v ibrations and crosswind as vortex-induced vibrations. The former becom e i portant at extreme wind speeds, regular vortex shedding causes the latter and occurs at any wind speed. In the case of vortex resonance, when considerable vibration ampl itudes develop, the structural displacements alter the fluid force, whi ch s known as an aero-elastic coupling of force an d structural response. Regarding the random load caused by turbulent wind, Davenport's pioneering concept of the gust respons e factor was applied to develop a simplified equivalent static load. Two di fferent models are available regarding the design f or vortex resonance. One is Ruscheweyh's approach to deal with vortex resonance s a forced vibration and to incorporate the aeroelastic effects in model parameters derived from experimental data. In the s econd model, the design for vortex resonance is bas ed on Vickery & ...