Measurements of the boundary layer on an effectively infinite rotating disk in a quiescent environment are described for Reynolds numbers up to Reδ2 = 6000. The mean flow properties were found to resemble a ‘typical’ three-dimensional crossflow, while some aspects of the turbulence measurements were significantly different from two-dimensional boundary layers that are turned. Notably, the ratio of the shear stress vector magnitude to the turbulent kinetic energy was found to be at a maximum near the wall, instead of being locally depressed as in a turned two-dimensional boundary layer. Also, the shear stress and the mean strain rate vectors were found to be more closely aligned than would be expected in a flow with this degree of crossflow. Two-point velocity correlation measurements exhibited strong asymmetries which are impossible in a two-dimensional boundary layer. Using conditional sampling, the velocity field surrounding strong Reynolds stress events was partially mapped. These data were studied in the light of the structural model of Robinson (1991), and a hypothesis describing the effect of cross-stream shear on Reynolds stress events is developed.

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Perdido is located in the Western Gulf of Mexico in 7,817 feet of water. It is being developed with cutting-edge subsea technologies to mitigate the project's key development challenges, which include extreme water depth, rugged seafloor terrain, low-pressure reservoirs, and aggressive hydrate formation tendency. This paper provides an overview of the Perdido Development subsea and flowline system and its associated flow assurance strategy. This paper also includes reviews of the design, fabrication, and installation of key subsea equipment such as twophase separators, subsea trees, manifolds, top-tensioned production risers, umbilicals, and flowlines. In particular, the two enabling subsea technologies, subsea boosting system and surface Blow-Out Preventer (BOP) for drilling and completing of subsea wells, are discussed. Unique features of the Perdido subsea system include:All wells are subsea (wet trees operated by umbilicals) and consist of 22 local Direct Vertical Access (DVA) wells and 12 offset wells.The subsea DVA wells are drilled, completed, and intervened through a single high-pressure drilling/completion riser and a surface BOP with the host rig.All production will flow from manifolds into five subsea boosting systems where gas will flow naturally to the topside facility, while liquids will be pumped using electrical submersible pumps (ESPs). Introduction The Perdido Development, jointly developed by Shell, BP, and CVX, includes the Great White, Silvertip, and Tobago fields and is located in the Perdido Basin and Foldbelt, in the Alaminos Canyon Protraction Area. This area is located in the western Gulf of Mexico, 200 miles south of Freeport, only eight miles north of the Mexico maritime border. All three fields are developed with subsea wells tied back to the host, which is a Spar with full offshore processing capabilities and pipelines for export.

The Perdido Regional Host is in the ultra-deepwater Gulf of Mexico, and produces from two Lower Tertiary horizons in multiple drill centers; some directly under the host SPAR, and others offset up to 7 miles and in water depths between 7800 and 9600 ft. All of the production is from relatively low-energy reservoirs, and posed considerable productivity challenges. The approaches to managing flow assurance risk and maximizing recoverable volumes were driven by the economically challenged environment in which the system was conceived and designed, and resulted in a unique host configuration relying on subsea wells and five high-powered ESP artificial lift systems with slug catching and two-phase separation accomplished on the seafloor. The final commissioning and early production characteristics of the system as related to the design intent and operational expectations will be described.The commissioning and early production phases of the development provided opportunities to validate Perdido subsea hydraulic models and operational methods that were considerably different from the typical approach employed by major oil companies in deepwater. Novel monitoring and surveillance tools generated by the project were benchmarked using early production data, and learnings were recycled into improvements to these models. This project is a considerable extension to previous systems, and due to the cost constraints of the risked recoverable volumes and high cost of operating in the ultra deep environment, it was imperative to advance the state of the art of flow assurance and operability.