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Emeraude v2.60 – Doc v2.60.01 - © KAPPA 1988-2010
Guided Interpretation #3
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B03 - 5/11
B03.2.1 • Imposing all positive contributions
Go to ‘Zone Rates’, and activate the ‘Contributions’ tab, Fig. B03.6.
Fig. B03.6 • Contributions
The dialog displays the list of the inflow zones, and the contribution for each phase. All values
in the dialog are editable; if a value is changed the cumulative rates are recalculated. If you
change a value before running ‘Global Improve’, the value can be fixed by checking the lock
checkbox. Contributions from the well bottom are zero and they do not need to be taken as
variables.
They are already locked.
Check the ‘Match surface conditions’ box.
Click on the ‘Positive’ button, then on ‘Global Improve’.
The Global Regression starts. Values inside the grid are updated after each iteration. This time,
all zones are treated simultaneously and the unknowns are the contributions. The goal is not
only to match the input measurements, but also to satisfy the defined constraints. When the
regression is over, a text at the bottom of the dialog gives the value of the objective function,
an indication of the match quality. It can be seen that the sign constraint has been honored
and the Global regression ends up with the best possible match, given those constraints and
the input measurements. As in the first step of the diagnosis, it is important to realize that the
Global regression only worries about the error on the calculation zones. The match outside of
those zones is simply not considered. Therefore, everything relies on the position of the
calculation zones, and the stability of the data in those zones. This is an essential difference
with the ‘Continuous’ method, described in section B03.3.
Validate the results with ‘OK’.