After movable-gel profile control and flooding technology is carried out in the sandstone reservoirs at middle-high water cut stage,the changes of the water cut are quite different from those during waterflooding stage.Aiming at the problem of no analytical model for quantitative water cut prediction after displacement,the paper establishes a water cut prediction model for gel profile control and flooding.Based on the production performance data and general relative permeability formulas,a water cut prediction model for waterflooding is derived and the physical meaning of each parameter of the model is explained,then a watercut prediction model is established for movable gel profile control and flooding.The paper uses the volume-weighted iteration method to calculate the equivalent viscosity and residual resistance factor of the gel solution,characterizes the effects of oil yield increase and water cut decline during the gel profile control and flooding process and carries out sensitivity analysis on model parameters influencing water cut changes.The study shows that reservoir heterogeneity and injected pore volume of gel solution affect water cut decline range and funnel width,and the equivalent viscosity and residual resistance factor have the most significant impacts on water cut decline.A test area is selected from the western Menggulin sandstone reservoir of Erlian basin for model test,and the error of the predicted water cut is less than 2％,meeting the requirement of engineering,which proves the feasibility of the water cut prediction model for movable gel profile control and flooding.%砂岩油藏在中高含水期实施可动凝胶调驱后,含水率变化特征与水驱阶段不同,针对目前凝胶调驱后缺少解析模型定量预测含水率的问题,建立了凝胶调驱含水率预测模型.通过油田生产动态数据,依据相渗通式推导了水驱含水率预测模型,解释了含水率预测模型中各参数的物理意义,并建立凝胶调驱含水率预测模型.采用体积加权迭代法计算凝胶溶液等效黏度和残余阻力系数,表征凝胶调驱过程中的增油降水效果,对影响含水率变化形态的模型参数开展敏感性分析.研究表明,油藏非均质性与凝胶溶液注入孔隙体积倍数影响含水率下降幅度与漏斗分布宽度,凝胶溶液等效黏度与残余阻力系数对含水率下降幅度影响最为显著.选取二连盆地蒙古林砂岩油藏西部试验区进行测试,预测含水率绝对误差小于2％,精度符合工程要求,证明凝胶调驱含水率预测模型具有可行性.
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