Vibration behavior of laminated couplings based on angular misalignment and nonlinear stiffness characteristics

The coupled bending-torsion vibration model of the laminated coupling was established, taking into account nonlinear stiffness, mass eccentricity, and angular misalignment. First, a laminated coupling vibration test study was conducted. The results showed that the average relative error between the numerical model and the test results was 10.2 %. Subsequently, the effects of the misalignment amount and nonlinear stiffness on the vibration characteristics of the laminated coupling were analyzed. The results showed that an increase in the angular misalignment amount leads to an increase in the vibration amplitude of the laminated coupling. Additionally, nonlinear stiffness has a suppressive effect on the vibration amplitude of the system. Finally, the effects of the angular misalignment amount, bending/torsional stiffness critical values, and rotational speed on the vibration behavior of the laminated coupling were observed using bifurcation diagrams. The research results show that when the angular misalignment exceeds 2.3 × 10⁻³ rad, the critical value of bending stiffness is greater than 8.44 × 10⁶ N/m, and the critical value of torsional stiffness is lower than 2.88 × 10⁶ N·m/rad, the vibration amplitude of the laminated coupling tends to rise, and resonance may occur. Additionally, controlling the laminated coupling vibration amplitude is more effective when the rotational speed is either in the low-speed range or the high-speed range. The research results detailed in this paper not only inform the design of laminated coupling parameters but also provide guidance for the assembly process.