Hoop layouts optimization for vibration reduction of L-shaped pipeline based on substructure-analytical model and genetic algorithm

In this paper, the dynamic model of the L-shaped pipeline with multi-hoop supports is established based on the substructure-analytical method. Firstly, the L-shaped pipeline is divided into two straight pipes and one curved pipe, and the displacement functions are assumed reasonably. Then, the artificial springs with large stiffness are introduced at the connection region between the straight pipe and curved pipe to simulate the rigid connection. Finally, the dynamic model of the system is obtained using the Rayleigh–Ritz method. This model can locate the position of the hoop more accurately and has higher computational efficiency. The experimental device of the pipeline system is built, and the simulation results are compared with the experimental results to verify the accuracy of the dynamic model. Considering that the reasonable design of the hoop layout can make the pipeline achieve the purpose of vibration reduction. Based on the established dynamic model, the maximum fundamental frequency and the minimum value of the maximum resonance response are selected as the optimization objectives, respectively, and the hoop position optimization models are created. The genetic algorithm is used for the optimization solution. Finally, taking the L-shaped pipe supported by double hoops as an example, the optimization calculation is carried out, and the best hoop installation position is obtained. The modeling and optimization methods proposed in this paper can provide guidance for the vibration analysis and practical application of aero-engine pipelines.