Application Research Of Well Testing Analysis For Horizontal Wells In Tight Gas Reservoir

Tight gas reservoir holds a large proportion in the total reserves of natural gas in ourcountry, and it has a very good development potential. Tight gas reserve generally refers to thelow permeability reserve that mainly products dry gas. According to the exploitation in lowpermeability gas reservoirs, many of them are in sandstone formation and there are also someexist in carbonate rock, shale，and coal formation. The technology of horizontal well is a veryimportant method for the tight gas development, which has been used more and more widely.Well testing analysis technique is a very important dynamic analysis method and basis torealize and evaluate the reservoirs as well as dynamic production monitoring. By means ofreasonable well testing analysis, we could comprehend and mastered reservoirs characteristics,predicted its productivity so as to master its dynamic production and exploit the reservoirseffectively. So this article developed deep study the method and theory of well testing analysisin hoirzontal wells according to the features of the tight gas reservoir. It is very common to usesome technologies to improve productivity, such as hydro-fracturing method.The results are as follows:(1)Establishing the well testing analysis model of horizontal well with infinite outerboundary conditions that are constant pressure or closed. The author considers some factorssuch as the stress sensitive, diffusion effect, and the sorption-desorption effect. The author alsoplotted the typical curves by the MATLAB sotfware, and made the thorough analysis to effectfactors.(2)Establishing the well testing analysis model of fractured horizontal well with thethreshold pressure gradient, stress sensitive, the adsorption-desorption effect. The authorplotted the typical curves by MATLAB, and made thorough analysis to effect factors.(3)Establishing the well testing analysis model of multi-fractured hoirzontal well in dualmedium reservoir. The author plotted the typical curves by MATLAB, and made thoroughanalysis to effect factors.(4)Well test models are added into Switf analysis sotfware. A case study was made toconfirm the above models.