Production Behavior of Fractured Horizontal Well in Closed Rectangular Shale Gas Reservoirs

Abstract

This paper established a triple porosity physical model in rectangular closed reservoirs to understand the complex fluid flowing mechanism and production behavior of multifractured horizontal wells in shale gas reservoirs, which is more appropriate for practical situation compared with previous ones. According to the seepage theory considering adsorption and desorption process in stable state, the gas production rate of a well producing at constant wellbore pressure was obtained by utilizing the methods of Green's and source function theory and superposition principle. Meanwhile, the volume of adsorbed gas (G L) and the number of hydraulic fractures (M) as well as permeabilities of matrix system (k m) and microfractures (k f) were discussed in this paper as sensitive factors, which have significant influences on the production behavior of the wells. The bigger the value of G L is, the larger the well production rate will be in the later flowing periods, and the differences of production rate with the increasing of M are small, which manifest that there is an optimum M for a given field. Therefore, the study in this paper is of significant importance to understand the dynamic production declining performance in shale gas reservoirs.