The critical parameters of a horizontal well influenced by a semi-permeable barrier considering thickness in a bottom water reservoir

Abstract It is well known that barriers have significant impact on the production performance of horizontal wells developed in a bottom water drive reservoir. In most cases, reservoir barriers are semi-permeable. Based on our previous research results on impermeable, semi-permeable barriers that ignore thickness, in this paper, a model is derived for a horizontal well of a bottom water drive reservoir with a semi-permeable barrier considering thickness. It also presents analytical equations to calculate critical parameters such as production rate, pressure and potential difference. The effects of barrier parameters on our model results were further investigated. The results showed that the larger the barrier size, thickness or the higher the barrier location, the higher are the critical parameters of a horizontal well. In a case, where the barrier permeability equals the formation permeability, the barrier width or thickness equals zero, the critical production rates converge to the same values of the case that has no barrier. When the barrier permeability equals zero, the problem is regarded as a case of impermeable barrier. This model can be applied to predict horizontal wells׳ critical production parameters in bottom water reservoirs with different size, thickness, and permeability of semi-permeable barriers.