![]() ![]() Linear element method for multi-angle fractured horizontal well in anisotropic reservoir. Journal of Petroleum Technology, 1968, 20 (9): 989- &.įANG S D, CHENG L S, XIN Y N, et al. Pressure transient analysis of naturally fractured reservoirs. The conclusions are applicable to similar nonlinear problems in pressure transient analysis. The numerical method is more suitable for polymer-flooding system. It is found that the permeability obtained with superposition principle method is very small, which shows that the superposition principle method cannot be used to solve the nonlinear model for pressure transient analysis in polymer-flooding system. Shut-in pressure data of an injection well in a polymer-flooding system was interpreted. It shows that shut-in bottom-hole pressure computed with superposition principle method is much lower than the numerical result for polymer-flooding system, which indicating that the superposition principle cannot be used for pressure transient analysis in polymer-flooding system. The shut-in pressures from numerical solution were compared with those obtained with the superposition principle method. The governing equations were discretized by finite volume method with a hybrid grid consisting of Cartesian meshes with radial refinement around well positions. Due to the maximum practical well-test duration limitation, the first five flow regimes (through composite flow) are more likely to appear in practice than later flow regimes.A mathematical model for pressure transient analysis in polymer-flooding system was established, in which the shear thinning effect of non-Newtonian polymer solution is considered. The natural gas hydrates parameter values in the Shenhu area of the South China Sea cause the prominent dissociated flow regime to conceal the later transitional and improvement flow regimes. The pressure derivative exhibits the same features as a homogeneous formation. Conversion of natural gas hydrates to natural gas becomes instantaneous as the dissociation coefficient increases. The dissociated-zone radius affects the timing of these flow regimes. A dissociation coefficient governs the difference in flow resistance between dissociated and non-dissociated natural gas hydrates regions. ![]() Natural gas hydrates formation properties govern the composite-effect, dissociated, transitional, and improvement flow regimes. In our model, a dynamic interface divides the natural gas hydrates deposit into dissociated and non-dissociated regions. A well's multi-branch structure governs the vertical radial and the linear flow regimes. The complete flow profile can be divided into nine distinct regimes: wellbore storage and skin, vertical radial flow, linear flow, pseudo-radial flow, composite flow, dissociated flow, transitional flow, improvement flow and stress-sensitive flow. A simplified form of the proposed model is validated using published analytical solutions. The interference among various branches is investigated using the superposition principle. For constant bottom-hole pressure production, the transient flow solution is obtained by Laplace transforms. This paper presents a new semi-analytical solution and the related methodology to analyze the pressure behavior of multi-branch wells produced from natural gas hydrates.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |