Nonlinear vibration isolation for fluid-conveying pipes using quasi-zero stiffness characteristics. (15th April 2019)

• Record Type: Journal Article
• Authors: Ding, Hu; Ji, Jinchen; Chen, Li-Qun
• Is Part Of: Mechanical systems and signal processing. Volume 121(2019)
• Page Start: 675
• Page End: 688
• Publication Date: 2019-04-15
• Subjects: Fluid-conveying pipe -- Nonlinear vibration -- Quasi-zero stiffness -- Nonlinear isolation; Structural dynamics -- Periodicals; Vibration -- Periodicals; Constructions -- Dynamique -- Périodiques; Vibration -- Périodiques; Structural dynamics; Vibration; Periodicals; 621
• DOI: 10.1016/j.ymssp.2018.11.057
• Languages: English
• ISSNs: 0888-3270

Abstract

Highlights: Vibration of fluid-conveying pipes is isolated by quasi-zero stiffness systems. Nonlinear solution is obtained via Galerkin method and the finite difference. The fluid flow can deteriorate the performance of vibration isolation. Abstract: Fluid-conveying pipes are always subjected to various excitations to cause unwanted vibrations. A quasi-zero stiffness system consisting of three linear springs is adopted as the nonlinear isolator to attenuate the transverse vibrations of fluid-conveying pipes induced by foundation excitations. A dynamic model of nonlinear forced vibration of the fluid-conveying pipe coupled with two nonlinear isolators is established for the nonlinear continuous system and validated by using two methods, Galerkin method and the finite difference method. The influence of the quasi-zero stiffness isolators on the vibration characteristics and vibration transmission of the pipe is investigated by analyzing the natural frequency, vibration mode, and nonlinear vibration response. The effects of flow speed of the fluid and the system parameters of the isolator are studied to evaluate the isolation performance. It is found that the quasi-zero stiffness isolator and fluid flow can shift several natural frequencies of vibration of the pipeline to the low-frequency region. When the linear stiffness of the vibration isolation is zero in the vertical direction, the first two modes of the bending vibration of the fluid-conveying pipe tend to become rigid mode. While achieving high-efficiency vibration isolation in the high-frequency region, the vibration in the low-frequency region is complicated. The flow speed of the fluid can deteriorate the performance of vibration isolation.