Study On The Influence Of Built-in Cable On The Fluid State In CT

The production system of submersible pump has the characteristics of high efficiency and low energy consumption,which has been widely used at home and abroad.As a submersible pump oil extraction system,built-in cable continuous pumping pipe is an important part of the pumping operation of the oil pump.It will change the flow characteristics in the process of oil recovery,directly affect the pump selection and oil production efficiency.Therefore,it is necessary to study the fluid flow in the coiled tubing in the deep well pumping process,so as to provide the basis for the selection of oil production equipment and parameters.Firstly,built the theoretical analysis model of the fluid velocity and pressure drop in the coiled tubing.Based on this,under the condition of constant flow rate of 0.890m~3/h,it is established a numerical model for the flow field of the crude oil in the coiled tubing with no cables and internal cables.It is obtained that the cable has little effect on the fluid flow in the tube,the flow rate decreases and the pressure drop increases.As the inlet flow increases from 0.099 m~3/h to 2.070 m~3/h,the variation law of flow field was analyzed.With cable bending increased from 0.000 to 0.990,the minimum cable bending degree of the secondary flow is 0.297,and the peak velocity of the gap is gradually increased and the peak velocity of the narrow gap is gradually reduced.When the cable bending degree e=0.594,the bending section increased from 3m to 80 m,the peak velocity of the flow in the coiled tubing is almost constant and the pressure drop increases.Simultaneously,the flow of crude oil is observed by observing the flow pattern of the liquid flow in the coiled tubing and the internal cable,the experimental result is basically accord with the numerical simulation result,it indicates that the numerical simulation of annular flow field is viable,and to validate the reliability of the results of the numerical simulation.In this paper,it is obtained the influence law of the built-in cable on the flow of crude oil and the influence factors of the fluid flow in the coiled tubing.It is of practical significance to study this kind of problems in drilling engineering and other fields in the future.