Submarine pipelines, as an important component of offshore oil extraction, play an important role in transporting oil and gas resources. Most submarine pipelines are laid using buried methods, but under the long-term erosion of ocean currents, the pipeline is prone to hovering and vortex-induced vibration, which can easily cause fatigue damage to the pipeline. A suitable installation position and length of spoiler can help suppress local erosion of the pipeline and enhance its self-burial effect. This article adopts the VOF soil water two-phase flow model and SST k-ω Turbulence model and Herschel-Bulkley model are used to establish a two-dimensional numerical model for local erosion of submarine pipelines, simulating erosion of clay seabed pipelines. By comparing and studying the local erosion profile, lift coefficient, maximum depth of erosion pits, etc. of pipelines, the impact mechanism of different installation positions and lengths of flow stoppers on pipeline erosion characteristics is analyzed. The results show that the spoiler installed directly above the pipeline will intensify local erosion, and as the length of the spoiler increases, the maximum depth and width of the local erosion pit in the pipeline will increase; A spoiler installed behind the pipeline and parallel to the direction of the incoming flow helps to suppress local erosion in the pipeline, reducing the maximum depth and width of the erosion pit; The bidirectional rigid spoiler installed at the bottom of the pipeline can effectively prevent local erosion of the pipeline. When the length of the bidirectional rigid spoiler is 3D or above, local erosion of the pipeline basically does not occur.