Abstract: A two-dimensional CFD model for local scour of submarine pipelines is established based on SST k-ω model, Herschel-Bulkley clay model and VOF two-phase flow model. The inflow velocity U and soil strength τ₀ are used as the variable parameters for the study of numerical simulation. By using this model, the law of the influence of different inflow velocities U and soil strength τ₀ on local scour characteristics of the submarine pipelines is studied by analyzing the bed surface pressure characteristics, shape of scouring pit, duration curve of scouring depth and local flow speed distribution on both sides of the pipeline. The results show that the local scour of the submarine pipelines in the clay seabed environment is affected significantly by inflow velocity. With the increase of the inflow velocity, both the local limit equilibrium scour depth and the width of scour pit increase, and the ratio of the increase in equilibrium scour depth to the increase in flow velocity tends, as a whole, to slow down. The local scour of submarine pipelines in the clay seabed environment is affected significantly by soil strength. With the increase of the soil strength, the seepage force of the seabed is weakened, the limit equilibrium scour depth of the pipeline decreases and the mound downstream of the pipeline is closer to the pipe axis. When the soil strength is greater than or equal to 300 Pa, it is more difficult to form a gap between the bottom of the pipe and the seabed.