抽油机井系统效率极限值的仿真研究

以油井供产协调方程为基础,建立了抽油机井动液面、产液量与抽汲参数之间关系的仿真模型,改进了以抽油杆柱动态仿真为基础的抽油机井系统效率仿真模型,并建立了基于抽汲参数优化设计的系统效率极限值仿真模型.分析了油藏参数、油井参数、设备类型与抽汲参数对系统效率的影响.仿真结果表明:系统效率随油井产能的增加而增加;含水率与气油比对系统效率有显著影响,气油比越大、含水率越低,系统效率越低;抽汲参数组合对系统效率有显著影响.对于低气油比、高含水、高产液量的油井,在优化设计抽汲参数条件下,抽油机井系统效率极限值可以达到50%,甚至超过60%.目前现场实际测试中所出现的50%以上的高系统效率是有科学依据的.

Simulating Maximum of System Efficiency of Rod Pumping Wells

On the basis of the inflow and outflow cooperative equations of oil wells,the models of simulating the functional relations of the moving liquid level,liquid productivity with the suction parameters were established,and the simulating models of the rod pumping system efficiency which were setup by simulating the dynamic behaviors of the rod string were improved. A new model of simulating the maximum of system efficiency of rod pumping wells,in which the suction parameters were optimized,was set up. By the simulating tests,the influence extent of which the oil reservoir characteristic parameters,beam pumping unit kinds and suction parameters affect the system efficiency was analyzed. The following conclusions were obtained by the simulating results:(1) the oil reservoir characteristic parameters remarkably affect the maximum of the system efficiency. The maximum of the system efficiency increases with the increasing of the oil well productivity,and when the gas/oil ratio is more,or the water content rate is the lower,the maximum of the system efficiency is the lower;(2) the suction parameters remarkably affect the maximum of the system efficiency;(3) for the oil wells of lower gas/oil ratio,higher water content rate and lower viscosity,if the oil wells run at the optimized suction parameters,the maximum of the system efficiency can be more the 50%,even more then 60% in some conditions.