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Submarine pipeline as a landward from the near-shore platform delivering oil and gas carrier transport due to its continuous throughput, easy management, has been widely used in marine engineering. However, the submarine pipeline in which the marine environment is generally very poor, wave, tidal and other water force in the pipeline near the end of the sand easily handling, erosion, resulting in the submarine pipeline erosion vacant, loss of stability, lead to breakage and other damage accidents , resulting in huge economic losses and environmental pollution. Based on a large wave of water the worse test, erosion stability of the pipeline on the seabed under wave action discussed. First, a brief review of the description of the advancing movement wave theory, the slight wave and Stokes second-order wave water particle trajectory speed were analyzed, and gives the wave theory applies draw LeMehaute (1970) The range of the map, as Stokes second-order wave theory based on test results used in the analysis of the proposed model. Secondly, for submarine scoured the key issues - sediment incipient problems are discussed. The starting conditions of the sediment is sediment movement critical hydrodynamic conditions. The sediment incipient problems under wave action is Sediment Studies topics at the forefront, so far, the vast majority of start-up criteria are based on the test results obtained, does not have universal applicability. Boundary layer theory based on the CCMei and MAFoda in 1981, the start of the wave boundary layer seepage penetration sediment, in the hope to improve the the sediment incipient guidelines under waves in theory. Once again, the wave flume physical model test, a combination of a variety of different working conditions, local scour around subsea pipeline. Observe and describe the physical processes of erosion development, measured scour depth of the bottom of the pipe, fitting of the experimental data analysis, the dimensionless scour depth and number of KC general regularity. Then, the numerical simulation of this paper VOF method and standard k-epsilon turbulence model flat-bottom solid wall at the end of the bed shear stress under wave action, calculation results show that the presence of the pipeline within the scope of its nearby local flow field had a greater impact , so that the wall shear stress is rising rapidly. Finally, the article on subsea pipeline erosion protection technology at home and abroad are introduced.
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