The energy industry continues to explore innovative technologies and measurement methods. Well completions have become even more complex today: many wells have multizone production capabilities and are equipped with advanced control devices, such as inflow control valves (ICVs). An even flow distribution can be achieved by controlling the zonal flow rates with the end result being more efficient production and longer lifetime of the well. One of the requirements to achieve this level of production optimization is to monitor the zonal multiphase flow rates in real time. Real-time zonal flow measurement downhole also helps detect production anomalies and reduce the need for surface well tests and facilities. This work carries a historical perspective: it is the third part of an ongoing effort that started in late 2007. In the first part, which was published in 2008, it was shown that the optical flowmeter provided invaluable information and operating successfully at most ICV settings, while for some specific ICV settings the excessive acoustic noise masked the flow signal. The findings from the first part were instrumental in improving the flowmeter design to tolerate higher acoustic levels. The new design, Gen-2 System, was tested rigorously under laboratory conditions along with the earlier Gen-1 System, and a Hybrid System, which were specifically designed for already-installed equipment. The design improvements and the results of this comparative laboratory work were the subject of the second part published in early 2010. This third part now focuses on the two separate field tests with the Hybrid System, which took place in 2010. The field tests revealed important facts in three key areas: flow measurement, well operation and well optimization. The test results demonstrated that the Hybrid System is capable of tolerating acoustic levels, which were not possible with the Gen-1 System, and that the issues related to excessive acoustics that masked the flow signal at some specific ICV settings in earlier tests have been largely eliminated. As a result, the Hybrid and the superior Gen-2 Systems can now be used in close proximity to control valves. The tests also revealed the fact that the use of surface choke system plays an important role in the well operation as it affects the flow conditions downhole. Finally, based on the flow measurement results and all the available data, optimum ICV settings can be determined for the production mode. The work also provided insight into the collaboration and feedback process during the course of the field tests. The current work, which represents the successful closure of an effort spanning a four-year period from 2007 to 2011, sets an excellent model that can be used to improve other technologies in the industry; that open collaboration between the operator and the equipment manufacturer can lead to advancement of technology and, as a result, provide more robust solutions.

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Innovative technology and measurement methods along with intelligent production optimization processes are important enablers with regards to intelligent fields and real-time reservoir management. Downhole multiphase flow measurement technologies play a major role in monitoring and optimizing well performance especially wells equipped with advanced well completions such as downhole inflow control devices (ICD) or inflow control valves (ICV). This paper builds on a pilot installation and comprehensive assessment of the world's first installation of downhole multiphase flowmeters and optical pressure and temperature sensors in a maximum reservoir contact (MRC) well in Saudi Arabia. One of the major findings from the initial study was that while the optical flowmeter operated successfully at most downhole choke valve settings, it was unable to make sensible readings at specific settings due to excessive acoustic noise. The results from the assessment were instrumental in improving the design of the flowmeter to tolerate higher acoustic noise levels. The initial appraisal and acceptance of this completion technology was closed by having the improved flowmeter manufactured and successfully flow tested under various laboratory conditions. The lessons learned from this experience have provided insights into downhole multiphase flowmeter sensing technologies, its capabilities and limitations. Furthermore, it demonstrates how open collaboration between operator and equipment manufacturer can yield reliable and fit for purpose equipment, a model that can be used to improve other technologies pertaining to intelligent fields and real-time reservoir management. BackgroundProduction optimization efforts have been the subject of a number of studies in the past within Aramco (Al-Bani et al. 2007;Arnaout et al. 2008;Mubarak et al. 2007Mubarak et al. , 2008. The current work builds on the previous work the subject of which was the performance evaluation of a permanent downhole monitoring system (PDMS).The PDMS was installed in world's first MRC and trilateral smart well in 2006. The three laterals were equipped with ICVs and PDMS comprising three 2-phase optical flowmeters integrated with pressure and temperature (P/T) gauges. The well was completed with 7" tubing and a deepset downhole sub-surface safety valve (SSSV) to accommodate future tubing electric submersible pump (ESP) installation. The ICVs, optical flowmeters and P/T gauges were located slightly up-hole from each lateral as shown in Fig.1.The PDMS has been designed with the philosophy of having low complexity and passive components downhole while keeping active electronic equipment on the surface to ensure high reliability and measurement accuracy. The 2-phase flowmeter and optical P/T gauge were built as a single integrated assembly (Fig. 2). The meter is full bore, non-intrusive, has no exposed sensors, moving parts or downhole electronics and has high resilience to erosion and corrosion. The PDMS system provides the production parameters required to determine the o...