Energy Analysis of Viscoelasticity Effect in Pipe Fluid Transients

Abstract

This study investigates the energy relations and dissipations in viscoelastic pipeline under fluid transients. The investigation is carried out analytically using energy analysis and Fourier transform techniques for viscoelastic waterhammer governing equations. The analytical results show that the viscoelastic term in waterhammer models is wrongly referred to in literature as being wave damping/dissipation when in actual fact it is the work done by the fluid on the pipe and vice versa. The energy dissipation is actually occurred in the pipe-wall due to the viscoelastic material strain. Moreover, the energy transfer/exchange between the fluid and pipe-wall and energy dissipation in the pipe-wall due to viscoelasticity effect is relating to the ratio of the pipe viscoelastic frequency and the fluid wave frequency.