Simulation And Optimization Of The Thick Oil In The Well

Heavy oil is an important part of petroleum energy,so many scholars have never stopped the study of heavy oil exploitation.One of the most important characteristics of heavy oil is high viscosity,poor mobility.The temperature sensitivity of heavy oil is very strong,can be used in high temperature heavy oil formations in the flow,but in the mining process,when the fluid in the wellbore,with the decrease of temperature of heavy oil viscosity increases,the friction resistance increases,pumping system load increases,resulting in pump pump card in severe cases,even pumping the rod rod broken phenomenon.At present,this method is often used for heavy oil mixing,chemical viscosity reduction and heating viscosity reduction.The dilution of heavy oil is a kind of important viscosity reduction technology,which has been widely used in Northwest china.Over a long period of time,the main problem of the heavy oil mixing is that it is not clear the condition of the wellbore,and the dilution ratio is increased blindly,which results in the increase of dilution and the waste of resources.In this paper,the numerical simulation software is used to simulate and analyze several common processes and problems in the process of dilution.The multiphase flow model and turbulence model of Fluent were selected with the process of heavy oil dilution,and Mixture was selected as the multiphase flow model,and the RNG k-e model was used as the turbulence model.Through the simulation of smooth tube,pure smooth tube blending plays a role is only a layer of thin oil film is formed on the pipe wall,reduce oil flow resistance,reduce the load of the sucker rod,and can not really achieve blending dilution viscosity reducing effect;increasing the blending ratio can enhance mixing the effect,must be used to stir the effect of diluting the implementation phase;other presence of gas has a reinforcing effect on mixing effect,reduces the effect of diluting water.SK type and SD type mixer can play a very good agitation and diluting effect,for the realization of mixer to achieve the optimal effect of SK type in the design aspect ratio should be controlled in about 5:3,and the width of the mixer is slightly less than the tubing size;for SD type mixer using small angle angle effect is the best when added with dilute;in effect,SD is better than SK type mixer mixer;when the diluting amount can meet to reach the viscosity value,and there is no need to increase by blending ratio when diluting mixer.The SK mixer has been improved,and the improved structure has been simulated.The simulation results show that the improved structure can better realize dilution.