Fluid effects on the pipe´s isolation plugging tool by large-eddy simulation

The isolation plugging tool is normally developed for deep water pipeline repairing. It is a mechanical structure of plugging and sealing fluid in high-pressure pipelines to make sure the pipe maintenance operation under normal transmission. In order to design control the plugging tool, the analysis of underlying flow field physics in pipeline is necessary based on the in-situ situation. The flow features of fluid adjacent to the plugging tool in the pipeline are analyzed by large-eddy simulation. The velocity vectors, pressure and energy loss distribution of the flow through the plugging tool are investigated. The force on the plugging tool is derived in three different directions. In order to analyze the bearing mechanism of the plugging tool with different dimensions, we compare the forces generated by the flow with different ratio of length of the plugging tool. The results show that the turbulent state in the downstream of the plugging tool is symmetrical about central plane. The periodical evolution of vortexes in downstream directly leads to the further development of turbulence. The vortexes are connected with the pressure distribution and energy loss. The influenced distance in downstream is twice as long as length of the plugging tool. The x and y directional total forces on the plugging tool are almost same and periodic. The length of the plugging tool is longer, the axial force is bigger on it.