Three-dimensional unsteady flow model of multistage fractured horizontal well in low permeability reservoir considering stress sensitivity.

In order to determine the effect of reservoir stress sensitivity on the inflow performance of multistage fractured horizontal wells during the development of low permeability reservoirs, a semi-analytical method was used to derive the point source function of infinite reservoirs considering stress sensitivity. Through perturbation transformation, Laplace transformation, superposition principle and other methods, the mathematical model of unstable seepage flow in multistage fractured horizontal wells during depletion development of low permeability reservoirs was established. Finally, the calculation accuracy of the model was compared with KAPPA well testing software. The results show that with the increase of production time, the stronger the stress sensitivity of the reservoir, the more upwarped the well test curve appears in the late flow period, and the upwarping time is advanced. Moreover, the sensitivity analysis of fracture geometric parameters and reservoir boundary size was carried out. [ABSTRACT FROM AUTHOR]