Flowmeters - Cased-Hole Log Analysis and Reservoir Performance Monitoring - page 71

Measurements in Horizontal Holes
The challenge in horizontal holes is even greater since gravity segregation of gas,
oil, and water can produce uneven flow regimes and flow directions. To combat
these effects production logging tool designers have made a number of flow mea-
surement approaches. In one, multiple small spinners are arrayed across the diam-
eter of the pipe, as illustrated in Fig. 5.15 .
Fig. 5.15 Vertically arrayed spinners in horizontal pipe. Image copyright Schlumberger. Used
with permission
An alternative approach uses a circumferential array of spinners to better map the
flow regimes in different sectors of the near horizontal flow pattern as illustrated in
Fig. 5.16 .
Fig. 5.16 Spinner array tool (SAT) in horizontal pipe. Courtesy GE Oil & Gas, 2014