驱油用聚合物溶液是粘弹性流体,当其在多孔介质中流动时由于拉伸变形会产生额外耗散,因此拉伸压降是不可忽略的.将Binding等人通过机械能平衡原理和最小能量原理建立的非牛顿流体入口收敛流动理论推广应用于渐缩毛管,并以幂指数关系表征剪切粘度与剪切速率关系、第一法向应力差与剪切速率关系、拉伸粘度与拉伸速率关系,从而建立了适用于描述粘弹性流体流动特性的渗流模型,分析了粘弹性流体在渐缩毛管中的渗流规律,利用建立的模型可以准确反映粘弹流体的渗流特性.
The polymer fluid for oil displacement is viscoelastic fluid, and it will produce extra dissipation when it is flowing in the porous media due to the extension deformation, so the pressure drop caused by extension can not be ignored. This paper applies the theory of non-Newtonian fluids in entry converging flow which is established by Binding on the basis of mechanical energy equilibrium principle and least energy principle to converging capillary. When the relationships between shear viscosity and shear velocity, the first direct stress dif- ference and shear velocity as well as extension viscosity and extension velocity are described as the power relationship, this paper establishes the percolation model to describe the flow behavior of viscoelastic fluid and analyzes the percolation law of viscoelastic fluid in the con- verging capillary. Applying the model established, we can describe the percolation characters of viscoelastic fluid accurately.