两相层流的复阻抗频散模型研究

Study of Complex Impedance Dispersion Model for Two-Phase Laminar Flow

在油气生产中含水率是进行产能评估和调整开发策略的重要指标,需要寻找一种更为经济有效的含水率检测方法。复阻抗频谱(CIS)检测技术是一种低成本、易实现、环保安全的快速检测方法,具有较大的开发潜力。基于复阻抗频散机理,结合Randles电路和Cole-Cole模型优势提出了一种适用于两相层流的复阻抗频散模型。研究制作了一套两相层流检测装置,并基于频谱分析和粒子群优化算法(PSO)反演获取模型参数,包括等效溶液阻抗、弛豫时间常数、频率相关指数、扩散阻抗系数以及弥散系数,并通过对照实验讨论了含水率和矿化度对模型参数的影响。实验结果表明,新模型计算值与实测值具有较好的一致性,同时模型参数与含水率、矿化度满足幂函数关系,可用于定量评价。该方法在传统测井采用的单频阻抗检测技术基础上修正了地层水矿化度影响,这对生产测井中的产能评估有重要意义。

Water content plays a vital role in evaluating production capacity and adjusting development strategies in the oil and gas industry.Therefore,it is imperative to identify a more cost-effective and efficient measurement method.Complex impedance spectrum(CIS) detection technology emerges as a promising solution,offering advantages such as low cost,easy implementation,environmental friendliness,and safety.This method exhibits tremendous potential for further development.To address the need for a reliable approach,we propose a complex impedance dispersion model for two-phase laminar flow,leveraging the strengths of both the Randles circuit and the Cole-Cole model.In addition,we have developed a specialized device for detecting two-phase laminar flow.By employing spectral analysis and particle swarm optimization(PSO) inversion techniques,we obtained key model parameters,including the equivalent solution impedance,relaxation time constant,frequency correlation index,diffusion impedance coefficient,and dispersion coefficient.Furthermore,we conducted controlled experiments to investigate the influence of water content and salinity on these model parameters.The experimental findings demonstrate a strong agreement between the calculated values derived from the new model and the measured values.Moreover,the relationship between the equivalent solution impedance,relaxation time constant,and both water content and salinity adheres to a power function.These outcomes provide a solid foundation for quantitative evaluation purposes.This method modifies the influence of formation water salinity based on the single-frequency impedance detection technology used in traditional logging,which is of great significance for productivity evaluation in production logging.