Water injection and stimulation treatments in vertical wells are routine techniques. Injectivity index forecast is however still a problem for many production technologists.
This paper aims at describing the various injection modes a vertical well in a high permeability reservoir experiences when increasing the injection rate. The apparent skin value is derived for each mode and is used to estimate the stabilized injectivity index of the well.
The following injection modes are considered: partial completion matrix flow, damage breakthrough with vertical extension of a forced fracture, radial forced fracture and forced fracture with lateral extension (PKN). Horsepower requirements are calculated in each case. In addition, Step Rate Tests are analytically simulated and discussed.
An actual multi-rate injection test is presented to support the theoretical developments of this paper.
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