海底混输管道砂粒运移与沉积特性研究OA

The multiphase transportation of oil and gas in subsea pipelines is often accompanied by sand particles.Under the action of gravity settling,sand particles may deposit at the bottom of the pipeline,reducing the flow area,resulting in increased frictional resistance and elevated energy consumption in pipeline transportation.Based on OLGA software,this paper establishes a simulation model for subsea multiphase oil-gas flow with sand transport.Taking a subsea pipeline as the research object,the effects of sand physical property parameters(including sand particle diameter,sand mass fraction,and density),pipeline inner diameter,and flow parameters(including gas mass fraction,total fluid flow rate,and outlet pressure)on sand transport and deposition are analyzed.The results show that the sand particles deposition is positively correlated with the sand particle diameter,sand mass fraction,sand density,and pipe inner diameter.In suspended flow,sand deposition is independent of the angle of repose but negatively correlated with the porosity.With increasing gas mass fraction and the fluid flow rate,the sand flow pattern transitions from stationary bed to moving bed and then to suspended flow.In the suspended flow,increasing the gas mass fraction and fluid flow rate,as well as decreasing the outlet pressure,will reduce sand particles deposition.In practical engineering,sand particles deposits can be removed by increasing the velocity to enhance sand-carrying capacity.The results of the research will provide theoretical support for sand deposition protection in subsea multiphase pipelines.