Nonlinear vibration analysis of pipeline considering the effects of soft nonlinear clamp

Soft nonlinear support is a major engineering project, but there are few relevant studies. In this paper, a dynamic pipeline model with soft nonlinear supports at both ends is established. By considering the influence of the Coriolis force and centrifugal force, the dynamical coupling equation of fluid-structure interaction is derived with extended Hamilton’s principle. Then, the approximate analytical solutions are sought via the harmonic balance method. The amplitude-frequency response curves show that different effects can be determined by approximate analysis. It is demonstrated that the increase in the fluid velocity can increase the amplitude of the pipeline system. The frequency range of unstable response increases when the fluid pressure raises. The combination of the soft nonlinear clamp and the large geometrical deformation of the pipeline affects the nonlinear vibration characteristic of the system, and the external excitation force and damping have significant effects on the stability.