Time-domain random vibration analysis method of pipeline based on time-frequency conversion

Characteristics of damping structures are essential for pipeline vibration design. In traditional random vibration analysis, it is currently challenging to take nonlinear variables caused by damping structure into account. Based on the theory of time-frequency conversion, this paper proposes a time-domain dynamic analysis method that converts random vibration load spectrum into a time-domain vibration signal satisfying Gaussian distribution by using the time-domain randomization method. First, using a simple beam model, the reliability of the time-domain analysis method was demonstrated by comparing random vibration results in frequency-domain and time-domain analysis. Notably, there is a 5% discrepancy in the stress root mean square error between the two approaches. In addition, the difference between the time-domain method and the frequency-domain method is analyzed for the actual pipeline structure, and the advantage of the time-domain method in practical design is proved by calculating the equivalent damping ratio. Thereafter, it was analyzed that the influence of friction coefficient, preload of damping clamp and different clamp configurations on pipeline vibration by applying the time-domain analysis method. The results indicate that the configuration and preload have a greater influence on vibration, but the friction coefficient has a smaller influence. It is evident from the aforementioned analysis that the time-domain random vibration analysis method's parameter setting is more adaptable, allowing for a more thorough investigation of the effects of different structural parameters on pipeline vibration and an improvement in the damping structure's design efficiency. © 2024 Beijing University of Aeronautics and Astronautics (BUAA). All rights reserved.