非线性双重介质模型的精确解及动态特征

考虑了二次梯度项的非线性双重介质模型．在模型中假设岩块和裂缝间的压力差作为初始未知量，在岩块中是拟先态的，从而避免了解联立方程组．利用广义Hankel变换求得了径向流动的解析解，由于解析解是无穷级数，无法得到具体的值．通过数值求解特征值问题，从而算得了窟体的压力值，并探讨了非线性参数和双重介质参数变化时压力的变化规律，给出了典型压力曲线图版，这些结果可用于实际的试井分析．

Exact Solution and Its Behavior Characteristic of the Nonlinear Dual-Porosity Model

A nonlinear dual-porosity model considering a quadratic gradient term is presented.Assuming the pressure difference between matrix and fractures as a primary unknown,to avoid solving the simultaneous system of equations,decoupling of fluid pressures in the blocks from the fractures was furnished with a quasi-steady-state flow in the blocks.Analytical solutions were obtained in a radial flow domain using generalized Hankel transform.The real value cannot be gotten because the analytical solutions were infinite series.The real pressure value was obtained by numerical solving the eigenvalue problem.The pressure law of the changes of nonlinear parameters and those of dual-porosity parameters was studied,and the plots of typical curves are given.All these result can be applied in well test analysis.