Buffeting of chimney stacks in winds
Abstract
When chimneys are erected adjacent to one another, the vortices in the wake of a windward chimney can cause buffeting forces on another stack. Strakes are ineffective as a cure to this type of oscillation, therefore dampers were designed to limit this resonant response. Such a damper consists of a ring suspended from three points around the top of the stack, and incorporates telescopic shock absorbers. Its efficiency is very sensitive to the tuning of its natural frequency to that of the chimney. The chimney frequency must be determined accurately either by calculation or testing, and problems associated with this are discussed. At a given frequency, the deflection, slope, bending moment and shear force at one end of a constant section element can be found in terms of those at the other end, by multiplying by a fourth order matrix containing simple trigonometric and hyperbolic functions.
 Publication:

NASA STI/Recon Technical Report N
 Pub Date:
 June 1980
 Bibcode:
 1980STIN...8221551R
 Keywords:

 Buffeting;
 Chimneys;
 Oscillation Dampers;
 Resonant Vibration;
 Vibration Isolators;
 Vibrational Spectra;
 Cylindrical Shells;
 Vortex Shedding;
 Wind Effects;
 Fluid Mechanics and Heat Transfer