Investigation On The Leakage Of Oil And Gas Under The Combined Action Of Wind Wave And Current

The present of this paper investigates the spread of oil and gas from marine pipeline under the action of combined current wave and wind.The experiment of leakage oil under shear flow has been conducted.The numerical investigate method of oil and gas leakage has been established.The experimental results and simulation results are compared to verify the reliability of the numerical method.The numerical investigation was carried out to study the influence of the flow conditions in the marine pipe and marine environment on rising behavior of leakage oil and gas.It provides an effective evaluation method for experimental research on spill tracking and capture.The method can be used as a reference for spill prediction and emergency disposal,which has theoretical significance and engineering application value.An experimental study was carried out to study the rising process of oil spill under shear flow.The effects of different external shear flow and leakage pressure were analyzed in detail.The underwater transport pattern of spilled oil are divided into three types.The pressure difference inside and outside of the leak determines the underwater transport pattern.During the whole floating process,the pressure difference dominates the initial stage,while droplet buoyancy is the driven force in the rest.In the numerical simulation study of combined current wave and wind environment,with the decrease of oil-gas ratio,the oil-gas rising speed becomes faster.The size of leakage natural gas becomes larger and distributed concentrated.With the increase of the leakage pressure,the faster the oil and gas rises,the more oil and gas flows out of leakage pipe in the same time.The trajectory of oil and gas column becomes vertical as leaking pressure increases.With the increase of current velocity,the speed of separated oil and gas increase when migrates to the downstream direction.The oil and gas separated from the mainstream at a lower water height and the separated time is relatively earlier.The migrating velocity of oil droplets on the surface become faster when the current velocity combined the wave velocity.With the increase of wave length and wave period,the pollution area of oil and gas becomes wider,and the oil and gas separates from the oil and gas column at a lower height.With the increasing of wind speed,oil droplets spread faster on the surface.When the velocities of wind and wave water are in the same direction,the oil droplets' velocity increases,while the velocities of wind and wave are in different directions,the oil droplets' velocity decreases.