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对两种类别的常用聚合物:多糖类(黄原胶)和部分水解聚丙烯酰胺(pusher-700)在玻璃珠人造岩心和贝雷砂岩中稳态流动的实验数据进行了分析。用振荡流测量计算聚合物溶解的最长弛豫时间(θf1),即本文所涉及的特征弛豫时间。两种聚合物的稳态流实验数据与所测得的聚合物自身的黏弹性数据一起被换算成在多孔介质中的平均剪切应力-剪切速率数据,因此就得到聚合物流在多孔介质中的平均幂律指数(n—)。用θf1、n—、岩石渗透率(k)、饱和度()和渗流速度(u)计算黏弹性数(NV),结果发现黏弹性数NV与多孔介质中的压力梯度密切相关。这种相关性是定义聚合物渗流黏弹性模型的基础,类似于达西定律。新的模型认为渗流速度和压力梯度呈非线性关系,这证实了聚合物的黏弹性变形,并且也证实孔隙的几何尺寸变化是聚合物的分子吸附和机械滞留所致。
The experimental data of steady flow in two types of common polymers: polysaccharides (xanthan gum) and partially hydrolyzed polyacrylamide (pusher-700) in glass bead artificial cores and Berea sandstone were analyzed. The oscillatory flow measurement was used to calculate the longest relaxation time (θf1) of polymer dissolution, which is the characteristic relaxation time involved in this paper. The steady state flow experimental data for both polymers, along with the measured polymer’s own viscoelasticity data, is translated into the average shear stress-shear rate data in the porous media so that the polymer stream is obtained in a porous media The average power law index (n-). The viscoelasticity (NV) was calculated using θf1, n-, rock permeability (k), saturation () and seepage velocity (u). It was found that the viscoelasticity number NV was closely related to the pressure gradient in porous media. This correlation is the basis for defining the polymer percolation viscoelastic model, similar to Darcy’s law. The new model assumes that the seepage velocity is in a non-linear relationship with the pressure gradient, confirming the viscoelastic deformation of the polymer and confirms that the change in pore geometry is due to the molecular adsorption and mechanical retention of the polymer.