摘要
根据特低渗透油藏流体渗流特征，建立了非线性渗流油藏数学模型。在黑油模型基础上，开发了特低渗透油藏非线性渗流数值模拟器。以五点井网单元为例进行算例分析，将不同类型的非线性渗流曲线与达西渗流模拟结果进行对比分析。模拟结果表明：与达西渗流相比，考虑非线性渗流规律的油井产油量低，产量递减快，注水见效缓慢，油井见水时间滞后；水井吸水能力差，注水沿垂直裂缝方向上的推进速度变慢；相同注采压差条件下，水驱效果差；水井附近憋压面积大，流体在地层中的流动消耗更多的驱动能量，降低了水驱效率；特低渗透油藏在开发过程中，除井筒附近地层压力梯度较大外，地层中大部分区域压力梯度较低，非线性渗流占据了地层渗流的主导地位，以非线性渗流规律为基础的数值模拟软件能够更准确地预测特低渗透油藏开发的动态特征。
A non-linear flow mathematical model is established according to the fluid flow characteristics in ultra- low permeability oil reservoir. The non-linear flow numerical stimulator is developed based on black-oil model. Taking a five-spot well pattern unit as example, and the comparative analysis between different types of non-linear flow curves and the results of Darcy flow simulation is conducted. The simulation results show that comparing with Darcy flow and considering non-linear flow, for non-linear flow, the low oil production, rapid production decline, low-efficiency water displacement and lagged injection response are obvious; of producing wells and water propul- sion speeds along vertical direction of artificial fracture are slow ; and moreover, water absorbing capacity of the injectors is poorer, the advance speed along vertical fractures becomes slower; under the condition of the same injection-production pressure difference, waterflood results are rather imperfect; the shut-up pressure area near the injectors is pretty large, more driving energy is exhausted for the fluids flowing in the formation, so the waterflood efficiency is reduced; in the course of oil-permeability oil reservoir development, except larger formation pressure gradient near the bole hole, the gradient in most part of the formation is rather lower, non-linear flow plays dominant role. Based on the laws of non-linear flow, the developed numerical simulation software can more accurately predict the dynamic characteristics of ultra-low permeability oil reservoir development.
出处
《大庆石油地质与开发》
CAS
CSCD
北大核心
2012年第1期75-79,共5页
Petroleum Geology & Oilfield Development in Daqing
基金
国家自然科学基金（10672187）和中国石油天然气股份公司重点科技攻关项目（06-02A-02-01）.
关键词
特低渗透
非线性渗流
数学模型
数值模拟
压力梯度
ultra-low permeability
non-linear flow
mathematical model
numerical simulation
pressure gradient
