Abstract
A floating raft system is subjected to multiple excitation sources with multiple frequencies for each excitation source. Considering the two characteristics of excitation source, the stability of floating raft system was analyzed. A vibration equation for the floating raft system under multiexcitation condition was established. A multiscale method was then used to solve the equation. The amplitude–frequency response equation and unstable region of solution are discussed. The results show that the vibration of raft frame fits the pattern of soft-spring vibration. This indicates that the excitation of main raft unit with a rigid connection compromises the stability of the system, whereas the excitation of unit with elastic connection increases stability.
Highlights
The vibration of a mechanical system is closely related to its stability and depends on the nonlinear nature of system [1, 2]
When the floating raft system is in the uncoupled state, the stability of steady solution of raft frame vibration is the stability of autonomous system at the singular point (b, r)
The same phenomenon was observed by nonlinear stiffness. This further proves that the excitation of unit with an elastic connection has the same effect as an increase in the virtual mass of raft frame, increasing the vibration stability of floating raft system
Summary
The vibration of a mechanical system is closely related to its stability and depends on the nonlinear nature of system [1, 2]. Zhang Qinglei et al [15] reported that in scenarios where the lateral vibration is coupled with longitudinal vibration, large errors occur if the system is only treated as linear This suggests that nonlinearity cannot be ignored when multiple excitation sources are present. Jon Juel Thomsen studied the characteristics of nonlinear vibration systems exposed to multifrequency excitation sources with high frequency bands [23] and the vibration of multicylinder diesel engines was investigated [24]. These efforts do not consider the existence of multiple excitation source. On the basis of the previous research, this paper combines multiple excitation sources with multiple frequencies, considers the different installation positions and connection modes of excitation sources, and analyzes the stability of floating raft system
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
