Numerical Simulation Of Erosion And Wear Of Fluid-solid Two-phase Flow In Collecting And Transporting Pipeline

The liquid-solid two-phase flow in the gathering and transportation process makes the pipeline bear the erosion corrosion effect,which is one of the main causes of material damage or equipment failure.Scour corrosion reduces the surface performance of the pipeline,especially at the variable diameter pipe,the possibility of scour corrosion is greater.Liquid-solid two-phase flow is widely used in storage and transportation,chemical industry,separation and other engineering practice,two-phase flow erosion wear is one of the important reasons for pipeline failure and failure,it is necessary to review and analyze the development of erosion wear model.In this paper,the essence and theory of erosion wear are introduced,and then the corresponding model is evaluated,the scour corrosion behavior is described by quality and energy balance,the existing problems and the direction of future development are pointed out,so as to describe the motion law well,and the fully coupled dynamic model of two-phase flow is established by considering the two-phase coupling method.And systematically describe the motion characteristics of liquid-solid two-phase flow,which provides a preliminary basis for the further development of liquid-solid two-phase flow model.The influencing factors of scour corrosion behavior are summarized,and the different parameters affecting the erosion and wear rate in the erosion simulation of several typical pipe fittings are summarized.The results show that the main factors affecting the erosion wear rate at typical pipe fittings are: impact angle,particle size,solid particle mass flow rate,liquid phase velocity,etc.The influence law of each influencing factor is introduced respectively.The effects of erosion angle,fluid velocity,solid particle size and particle mass flow on the scour corrosion behavior of venturi tube were investigated.Based on the principle of computational fluid mechanics and fluid-solid coupling,through CFD mid-stream solid coupling technology,the standard k-? Eddy current is used for numerical analysis and discrete phase model(DPM)to analyze the flow field of the liquid-solid two-phase flow on the scour corrosion behavior of the mound Tube,and to predict the location of scour corrosion behavior at the variable diameter pipe.The application of shrinkage angle in 10°~70° tube,inlet flow rate in 8~20m/s,solid particle size in 6.25~300?m,mass flow in the 0.2%~0.8% range of the effect of scour corrosion behavior.The results show that the maximum erosion rate has a strong dependence on shrinkage angle,liquid flow rate,solid particle size and solid mass flow.Different structural parameters the location distribution of scour corrosion behavior in the mound tube is basically the same,but the degree varies.The shrinkage section(throttle area)is the most prone to scour corrosion behavior,and the scour corrosion behavior of the lower half of the pipeline is more serious.In addition,the optimum impact resistance angle is obtained,and the influence of erosion angle,fluid velocity,particle size and mass flow on scour corrosion is investigated.This paper also introduces the methods to prevent erosion wear,and summarizes the research on pipeline erosion and wear in recent years,in which the study of bionic pipe fittings and composites is very important,and puts forward the future research direction and the improvement of erosion wear.