多孔介质中滞留聚合物分子的粘弹效应模型

本文对三种不同的人造岩心用部分水解聚丙烯跳胺溶液进行了流动试脸，发现在水泥和环衷树脂胶结的不均质石英砂岩心中具有粘弹效应;而在致密的磷酸铝烧结的刚玉砂岩心中未发现粘弹效应。根据测出的残余效应系数分析，认为这可能与岩心的孔隙结构、渗透率等因素有关。对存在粘弹效应的岩心，基于开尔文模型，作者提出了多孔介质中滞留聚合物分子产生回复形变的教学模型。对于试脸曲线，用最小二乘法拟合出流量与时间的关系式，它与聚合物分子回复形变的数学模型具有一致形式，于是本文从理论上论证了滞留有聚合物分子的多孔介质中，在降低水的流动压差至稳定后，流量随时间呈指数变化的规律是滞留聚合物分子的粘弹性造成的。

MATHEMATICAL MODEL FOR VISCOELASTIC EFFECT OF-POLYMER MOLECULES RETAINED IN POROUS MEDIA

The tests for the flow of a partially hydrolyzed polyacrylamide in three different sand packs have been conducted in this paper, The viscoelastic effect is found to exist not in compacted corundum sand cores sintered with aluminium phosphate but in quarts sand cores cemented by cement and epoxy resion, This phenomenon is believed to relate to the pore structure and permeability o} cores, For sand cores showing the viscoelastic effect，on the basis of Kelvin model，a mathematical model has been given for descibing the restoring deformation caused by polymer molecules rate fined in porous media. This model shows that pressure being stable，the change of flow rate with time accords with an exponential reaction when the cores are washed by the water until flow rate becomes constant and then the pressure is let to reduce. And the validity of this model is analyzed in this paper as well.