The relationship between filtration of liquid from the reservoir into the well and infiltration into the reservoir

The article is devoted to determining the laws that govern the movement of fluid from the well into the reservoir and back. To study this pattern, the authors conducted experiments on a circular model. Based on the analysis of the experimental results, the following pattern was revealed: when a certain amount of liquid is injected into the reservoir, significantly less repression is required than depression is required when the same amount of liquid is taken from the reservoir. From what has been said, it can be concluded that the pick-up coefficient in all cases is significantly higher than the productivity coefficient. In addition, a certain pattern has been revealed between reservoir pressure and pressure gradients in the bottom-hole zone of the formation. This pattern also lies in the fact that the lower the reservoir pressure, the greater part of the total depression falls on the bottom-hole zone of the formation. This suggests that outside the bottom-hole zone of the formation (critical zone) at low pressure, the value of pressure gradients is insignificant. Therefore, a significant part of the pressure gradients falls on the critical zone. Of course, the work done does not pretend to be a complete study, but it nevertheless shows that the influence of local resistances must also be taken into account in hydrodynamic calculations. Keywords: Fluid movement; Filtration from the formation into the well; Infiltration into the formation; Bottom-hole zone of the formation; Critical zone; Modeling.