一种新的注入井大孔道解释模型

摘要

In the late stage of water-flooded sandstone oil reservoirs, the high-capacity/permeability channels ( HPCs) are bound to develop to a different degree. In order to effectively identify the development degree of HPC and provide the evidence for the amount of succeeding plugging agent, a new model for the injectors is proposed based on current HPC well-test intepreting models, this radial model considers the interdependence between HPC and non-HPC blocks of the injectors. The changed characteristics of the bottom hole pressure ( BHP) of the wells in a different degree are analyzed by adjusting two parameters; the development area and multiple responsing the developed status of these HPCs; This model can not only rapidly re-present the changed process and characteristics of the pressures before and after the shut-in of the wells, but accord with the the rules of the field supervision. The result analyses show that considering the obvious influence of the cross flow on the BHP, the quantitative characterization of the HPC volume can be realized under the conditon of one confirmed parameter with the help of the determined HPC development degree by the curve matching. The achievements stated above possess a certain guiding significance for the measurement of the HPCs.%砂岩油藏注水开发后期一般都会发育有不同程度的大孔道.为了有效识别大孔道发育程度,对后续调堵剂用量提供依据,在分析目前常用大孔道试井解释模型的基础上,提出了一种考虑大孔道与非大孔道区域相互耦合的注入井径向模型.通过调整反映大孔道发育状况的发育面积和发育倍数两个参数,分析不同发育程度下注入井井底压力变化特征；该模型可以快速再现关井前后压力变化过程和特点,符合矿场监测规律.结果分析表明,考虑窜流影响对井底压力影响明显,通过曲线拟合确定大孔道发育程度,在一个参数确定的情况下可以实现大孔道体积的定量化描述.研究成果对于大孔道治理有一定指导意义.