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Emeraude v2.60 – Doc v2.60.01 - © KAPPA 1988-2010
Guided Interpretation #4
•
B04 - 5/14
‘Apparent Downflow’ can occur in deviated wells with a high heavy phase holdup. In a deviated
well with a high water holdup, the water may be dragged upwards by the oil flowing up on the
high side of the pipe, and fall back on the low side of the pipe. This circulation of water may be
‘seen’ by the spinner as only downward flow when it is in fact due to upwards oil flow. Deciding
that the flow is up when the spinners says it is down, can be done if additional information is
available (zone pressure, temperature, etc).
An ‘Apparent downflow’ option in the Zone Rate dialog can be used for quantitative
interpretation. The option is available in both Liquid-Liquid and Liquid-Gas cases and is offered
regardless of the sign of the apparent velocity VAFLOW. In this option, the rate of the light
phase Qlight (Qhc in our case) is assumed to be a function of the slip velocity, Vs and the
holdup of the heavy phase: Q
light
= C
ADF
x (Vs+V
ADF
) x (1 – Y
heavy
) x A
pipe
where C_
ADF
and V_
ADF
are editable parameters (accessed in the ‘Edit' dialog, respectively set to 1 and 0 by default).
The spinner measurement is disregarded and the superficial velocity of the heavy phase is set
to 0. The match is preferentially on water holdup. Yet because of the larger water holdup the
density is certainly more reliable here.
Select the ‘Table’, ‘Unfit’ the capacitance (Zone 3 only).
Select the ‘Plot’ and click ‘Improve’:
Fig B04.7 • Rate Calculation tab
Select the bottom zone and set it to ‘No Flow’.
Validate with OK and generate the schematic logs, Fig B04.8.
The simulated channels change value linearly across the inflow zones. The simulated apparent
velocity data are not relevant wherever Apparent Downflow applies. This is because the
VAFLOW model disregards VAFLOW completely and uses holdup/density measurements only.
Also, for the top reservoir, the contribution shown on the schematic is assigned linearly to the
corresponding inflow zone. This of course, is different from what the spinner ‘sees’ since the
top reservoir contribution is entering only at the level of the sliding sleeve. Since we are using
the ‘Zoned’ interpretation method this is not an issue.