Vortex Excitation of Metal Bellows

Abstract

The present paper extends the results presented in an earlier paper, and pertains to the prediction of vibratory amplitudes and stress levels resulting from flow-induced vibrations of metal bellows. Included is visual verification of the vortex shedding-bellows convolution coupling phenomena. Two methods for predicting flow excitation amplitudes are described. One method, called a “Stress Indicator” method is a simplification of the other, and allows rapid estimates of bellows dynamic stress values. This simplified method is complemented by a plot of “Stress Indicator” versus number of cycles to failure, obtained from experimental data for actual bellows failures. The influences of bellows damping and acoustical resonances are discussed.