聚合物驱弹性效应对注入压力的影响

引人综合粘度度量聚合物溶液的粘弹性，利用无限大地层达西定律，导出了粘弹性流体径向流的压力损失方程。采用数值方法研究了粘弹性流体在变截面孔隙模型中的阻力特性，结合实例分析了粘弹性流体径向流的压力损失随粘弹性的变化规律。研究结果表明，弹性效应是影响注入压力升高的一个重要因素。聚合物溶液的粘弹性越大，其在地层孔隙中的渗流阻力越大，弹性效应在增高注入压力中所占的份额也越大。增加地层渗透率、降低注入排量、减小聚合物溶液的粘弹性均有利于降低注入压力，提高注入能力，改善注入效果。

Influence of elastic effects on injection pressure of polymer flooding

Pressure drop equation of viscoelastic fluid was given with compositive viscosity measuring the rheological property of viscoelasticity of polymer solution and Darcy law of radical flow in infinite formation used. Flow resistances of viscoelastic fluid in typical pore models with varied cross section were studied by numerical method and one instance was taken to demonstate the relationship between pressure drop in radical flow and viscoelasticity. Results showed that elastic effect was an important factor in result of high injection pressure. The larger viscoelasticity of polymer solution, the higher percolation resistance, and the greater of proportion of high injection pressure arising from elastic effect. Increase in permeability and decrease in injection flow rate and viscoelasticity were in favor of decreasing injection pressure ,enhancing injection ability and efficiency.