Research on Method of Gas Well Production Analysis in Edge-Water Gas Reservoir

Gas well production analysis is a method that can calculate formation parameters like permeability, skin factor, half length of fracture, single well controlled radius and single well controlled reserves through fitting and analyzing towards daily production data and decline type curves. Now, this analysis method that has been common used is mainly Arps[1], Fetkovich[2], Blasingame[3], Agarwal-Garder(AG)[4], Normalized Pressure Integral (N.P.I)[5] and FMB[6]. Among them, Blasingame method considers material balance pseudotime and pseudopressure that make the analysis results more accurate. This paper takes method of Blasingame production analysis in edge-water gas reservoirs as the main object of research. It starts from building the model of two phase seepage of gas-water in this kind of reservoir. By calculating, it obtains solution of the model above. On this basis, programming in C language and applying Stehfest[7] method to inverse the solution of the equation in Laplace space. And then, it gets a series of data of dimensionless time and its corresponding dimensionless production in the real space. Further, it deals with these data in Excel. Finally, it obtains the Blasingame type curves of gas-water co-production well in this reservoir. This paper provides a theoretical basis to production analysis of edge-water gas reservoir.