Numerical Simulation And Experimental Study On Gas Performance Of Gas Lift Valve

The gas lift valve is the main downhole tool for offshore gas lift.The flow and working characteristics of the gas lift valve directly determine the oil recovery efficiency and production cost.At present,most oil well production pipelines in the sea do not have a downhole pressure gauge.It is impossible to analyze the lift dynamics.If the production abnormality is encountered,it is impossible to determine whether it is the cause of the formation or the cause of the lift.In addition,some gas lift valves are not well designed,and there are limits to the gas injection rate required to obtain a stable oil pipe and casing fluid,the highest working pressure is low.Although some gas lift valves are applied to the drainage and gas recovery measures,they lack the evaluation of their working conditions and cannot adapt well to the downhole production conditions,which affects the gas field development effect.Therefore,the gas lift valve experimental platform was established.By measuring the flow rate and working characteristics of the gas lift valve,the stability and working performance of the gas lift valve were evaluated,and the shape and size of the gas lift valve nozzle were optimized.The shape and size of the gas lift valve are important factors affecting the gas flow and pressure loss.In this paper,the shape and size of the nozzle are optimized by the combination of numerical simulation analysis and experiment,which provides the basis for the design and trial production of the gas lift valve.In the paper,the Fluent software is used to simulate the nozzles of different shapes and sizes.The shape and size of the gas lift valve nozzle are optimized.The simulation results show that the large diameter Venturi nozzle is more suitable for working under high pressure and large displacement.The shape and size of the nozzle were also optimized by experimental methods.The gas lift performance test and flow performance test were carried out.The results show that the results show that at the same flow rate,the inlet pressure of the cylinders of equal diameter and the round table mouth is higher than that of the venturi nozzle,and the inlet pressure decreases as the diameter of the venturi nozzle increases.The diameter of the nozzle is larger,the increase of the inlet pressure with the flow rate is the smaller.The 6.1mm-7.1mm venturi nozzle is more suitable for the 1-inch gas lift valve to work under the high pressure and large displacement environment.The experimental results of the inlet pressure test show that for venturi,cylinder,and circular table nozzles of equal diameter,the inlet and outlet pressure ratios corresponding to the critical flow rate of the venturi nozzles under differentdisplacements are all above 90%,which eliminates the contingency of the preferred shape.It proves that the venturi nozzles have better work performance.The test of the outlet pressure shows that the flow rate rises rapidly with the increase of the inlet pressure before the flow reaches the critical flow rate.After the critical flow rate is reached,the growth trend becomes slower and has a linear relationship with the inlet pressure.As the outlet pressure increases,the critical flow rate gradually increases,and the critical flow rates of the same nozzle at different outlet pressures are on the same line.The numerical simulation and experimental results can provide theoretical basis and reference for the design,trial production and gas lift valve of the gas lift valve in the deep sea.