Vibrational response of thin tubes to sequential moving pressures

Abstract

This paper presents a set of analytical solutions for the vibrational behavior of thin tubes under sequences of internal moving pressures. Such analyses are applicable to a number of theoretical and practical problems, like transient dynamic response of arteries due to pulsatory blood flow, transient deformations of gas pipelines due to pressure fluctuations, or the vibrational response of pulse detonation engines (PDE). However, the presented solutions are tailored for successive applications of specific loading profiles that represent gaseous detonations. The solutions are compared with the available experimental data and complementary finite element simulations. Representative analyses are carried out for an experimental detonation tube under loading spectra traveling with different time delays. It is shown that the resulting vibrational spectra can be highly affected by the frequency of the sequential loadings and high dynamic amplification factors can exist even at non-critical speeds. It is also shown that application of sequential moving pressures with proper loading frequencies can substantially reduce the structural vibration.