Abstract
In well testing, the subject of study is composed by the reservoir, wellbore and piping.
The traditional well testing interpretation approach focuses in the transient behavior of the pressure inside the reservoir. Flow rates are considered input information; generally assumed instantaneously constant during each flow period.
On the other side, the traditional nodal analysis concentrates in the pressure drops inside the wellbore and pipelines reducing the behavior of the reservoir to a pseudo-stationary state.
These simplifications can be applied for a limited period of time in high potential wells.
However, especially in low potential wells, the productivity index varies continuously, flow rates can not be approximated by constant values; the effects of liquid loading, slugging, and other regimes of multiphase pipe flow affect decisively the conditions in the reservoir. Understanding system's operation implies the analysis of every component and the relations between them.
