Development of oilfields characterized by low permeability and porosity, and a low rate of fluid filtration in the reservoir results in an increase in the well test duration (over 1000 hours) to determine reservoir pressure, productivity index and hydraulic conductivity of the layer. In such cases, there is the problem of providing the necessary comprehensive exploration while minimizing losses of oil production.
The authors considered model examples of well tests of reservoirs of low-permeability, lateral heterogeneity and for different boundary conditions. Simulation of the lateral inhomogeneous layer showed that for the formation pressure control under the reservoir development it is sufficient to define the reservoir pressure at the boundary of the change of filtration properties. Analysis of simulation results revealed that the Horner method has higher accuracy in the case of homogeneous infinite reservoir. In the case of laterally inhomogeneous layer, the presence of impermeable boundaries or limits of the constant pressure differential method allows to estimate the formation pressure with minimal error and with less duration build up.
Obtained in the course of numerical experiments the results are recommended to be used for the rapid assessment of the duration of the build up at the research planning stage and in monitoring the recovery process the bottom-hole pressure in real-time to predict the duration of the stop producing well.
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