关键词: 双重介质, 水平井, 产量递减, 典型曲线

Abstract:

Horizontal wells have advantages for the development of particular reservoirs. In order to solve the complicated seepage flow problem of horizontal wells in dual porosity media, based on WarrenRoot model, the 3D transient model was established in this paper. The solutions of dimensionless bottomhole pressure at constant rate condition were obtained by modern mathematical methods including the Laplace transformation, finite Fourier cosine transform, and superposition integral. The solutions of rate at constant bottomhole pressure were solved by Duhamel convolution principle. McCray integral average production decline equation was built based on redefined dimensionless groups. Dimensionless production integral average decline and its derivative at constant pressure condition were programmed and plotted by Stehfest numerical inversion. The results show that type curves of production integral average decline derivative exhibit characteristics of dual porosity media. Applications of type curves matching production data can predict rate and calculate reservoir parameters.

Key words: dual porosity media, horizontal well, production decline, type curve