Study On Dynamic Analysis Method Of Typical Curve Of Water Gas Reservoir

Water-bearing gas reservoirs have been accounted for a large proportion in development of gas reservoirs. On the one hand, water production in gas well reduces reservoir recovery and increases the cost of reservoir development. On the other hand, the conventional methods of dynamic production analysis are limited, causing more difficulties in the curse of dynamic analysis of water-bearing gas reservoirs. Therefore, the more production performance we know, the more efficiently the water-bearing gas reservoirs can be exploited.The dynamic analysis of typical curves is an important method during production performance analysis. Considered single-phase flow in formation or wellbore only, this typical curve dynamic analysis of single-phase flow can simply analyze dynamic characteristics of gas production in gas reservoir production performance analysis, ignoring the effects of water production on production performance of gas wells. Given the limitation of the typical curve dynamic analysis of single-phase flow, taking accounting of water reservoir production characteristics, combined with two-phase seepage theory of gas reservoirs, a mathematical model of gas-water two-phase seepage flow has been established whose analytical solution can be obtained by Laplace transform and Stehfest numerical inversion method.By means of redefining the dimensionless variables, typical curves of gas-phase and aqueous-phase for air-water two-phase dynamic analysis method have been plotted using program worked out by Matlab software. Utilizing dynamic analysis method of gas-water two-phase typical curve and RTA software to match gas production in a water-bearing gas reservoir respectively, the results indicate that typical curve dynamic analysis method of gas-water two-phase can overcome the disadvantages more effectively that production data locates right of theory curve for typical curve dynamic analysis method of single-phase flow. Besides, the negative influence of water production on gas production matching has been weakened in some degree. Moreover, the two-phase dynamic analysis method is more conducive to analyze production performance, extending the application scope of the method, leading to a significance.in dynamic analysis of water-bearing gas reservoir.