Simulation And Optimization Method Of Energy-Saving Of Rod Pumping Wells In The Overall Block

At present, the single wells are taken as researching obejects in parameters optimization design. It can not insure the engergy consumption in the whole oilfield or block is the least, when the planned oil output is achieved. Aiming at the shortcoming of single-well optimization design, and basing on the depth research in IPR curve, simulation model of system input power and optimization design method of single-well, the new optimization design method of suction parameters of the integrate energy-saving all rod pumping wells in an oilfield was built. The main innovation in this paper includes:(1)The calculating model of liquid phase flowability coefficient in oil-gas-water multiphase flow is setup. Basing on that, the oil-gas-water multiphase flow IPR curve common model is built, which holds the character of breakpoint.(2)Basing on the well bore multiphase flow theory, the pipeline characteristic relationshipe curve is established. Considering IPR curve, discharge characteristic relationshipe curve of pump and pipeline characteristic relationship curve, the system inflow and outflow cooperative coupling simulation modles are setup. The simulation precision of inflow and outflow cooperative point is raised. It lays a theoretical foundation for system optimization design.(3)Calculating the submergence pressure and the discharge pressure of oil well pump with multiphase flow theory, the bottom boundary conditions of the axial vibration of rod string was improved, and the simulating models of the motor's input power which were based on the axial vibration of rod string and the simulating of the polished rod dynamometer card were established.(4)Based on the restraint condition of single-well output ,design models in which the least system output power was taken as the optimization design objective function. Based on the result of the suction parameters and the least input powers of an oil well were optimized when the single oil well is of different outputs, and the recursive models between the least input power and its outputs of the single well were set up.(5)Based on the recursive models, and the single-well output taken as the optimum design variable, and the planed crude oil output of all oil wells in an overall oilfield considered as the restraint condition, the entire optimization design models in which the least input power of the overall oilfield was taken as object were set up.(6)Using Visual Basic 6.0 to develop"Simulation and optimization of system to the least energy consumption of overall oilfield". The result shows that the total power consumption can be much less when the parameters are designed by the entire optimization method, the effectiveness of energy saving is remarkable, and the application prospect is wide.