Fluid-solid coupling numerical analysis of dynamic vibration characteristics of the Pipeline Inspection Gauge (PIG) in the pipeline

The Pipeline Inspection Gauge (PIG) produces complex vibration behavior in the process of running the tube due to the impact of the fluid and the non-linear material properties of the polyurethane rubber bowl. In order to study the non-linear dynamic vibration characteristics of the PIG in the pipeline, a Coupled Euler-Lagrangian (CEL) method is used to establish the fluid-solid coupling model of the PIG in the pipeline. The complex dynamic vibration behavior of the PIG in the tube running through the pipeline local deformation is solved and analyzed in this paper. The results show that when the PIG is running in the pipeline, the tightness degree of the three cups and the inner wall of the pipe decreases in turn, and the friction also decreases in turn; When passing through the local deformation area, the velocity, acceleration and the pressure difference fluctuates greatly, which will still last a period of time after the deformation area. The maximum stress and the true strain of the three cups are reduced in turn when passing through the local deformation area, which appeal in the place where the bowl is fit with the middle compartment. The influence of the inertia impact of the PIG and the effect of the friction are taken into account in this paper, making the fluid-solid coupling model closer to the physical reality, which lays the foundation for the optimization of structure design and application of the PIG.