Simulation Analysis on the Influence Factors of Erosion Damage of Typical Elbows in Gathering and Transportation Pipelines

In this paper, the erosion damage problem of typical elbows of gathering and transportation pipelines was studied. The calculation model of wall erosion damage of natural gas pipe was established by solving the turbulence equation, and the erosion rate of elbows was determined. A typical geometric model of natural gas pipeline was constructed according to the results of the pipe fitting erosion rate, and the fluid motion state in the pipeline and liquid–solid impact on the surface of pipe fitting were analyzed to obtain the simulation results. According to the simulation results, the physical parameters of natural gas are set to improve the calculation accuracy and efficiency. Experiments have revealed that the initial velocity, particle size, relative molecular weight, viscosity, and impact angle of natural gas particles significantly affect pipe erosion. Especially when the velocity exceeds 3 m/s, the particle size increases, or the impact angle is greater than 30°, the erosion failure rate increases markedly. Conversely, high viscosity tends to reduce erosion. At the chosen time point of 10 years, the difference between the simulated erosion rate and the actual observed erosion rate is 0.04, indicating reliable results.