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Self-similarity and the need for subsea technology. Outline of presentation. Trends & challenges Technological needs Research needs. ?. Trends. Since the early 80’s the global production rate has exceeded discoveries
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Outline of presentation • Trends & challenges • Technological needs • Research needs
? Trends • Since the early 80’s the global production rate has exceeded discoveries • Number of new discoveries of Giant and Super Giant fields (Ultimate Recoverable Resource (URR) > 500Mbbl) decreases • Is global oil production about to peak?
North Sea US Norway Self-similarity? • Production histories from selected oil provinces look very similar • This self-similarity may suggest an eminent peak in global oil production • Increasing focus on • Increased Oil Recovery • production from small fields (URR<50Mbbl) • Heavy (ultra-heavy) crudes
Potential IOR in large fields • Average recovery factor in NCS is less than 50% • Total volume of unrecoverable reserves > 3000 MSm3 oil (~5 x GDP)
98 78 5% more oil 63 59 60% more fields Small fields are challenging • Small fields do not contain much oil (by definition!) • Development of small fields is only possible when • Field development costs are low • Operating costs are low
2006-2010 1995-2000 2001-2005 Subsea field developments • Trends • Development of smaller fields • Development of large fields subsea-to-beach • Being able to predict what happens in flow lines and processing units is key to success • Further development of accurate simulation tools is crucial
Current modelling approaches • OLGA • 1D frame work, pre-integrated 2D model for stratified flow • LEDA • Coupled 1D-3D simulator, 1D/2D for pipe flow, 3D for processing units • Fluent, StarCD, CFX • 3D codes
CFD 1D models Physical complexity Simplified 1D models 101 107 105 103 L/D Hierarchy of models • CFD • Reasonable on “short” length scales • Difficulties with interacting dispersed phases and free boundaries • Difficult closure relations (turbulence/dispersed phase interactions) • 1D models • Difficulties on short length scales which influences long-scale phenomena • Difficult to get closure relations which are universally valid
Simulation time CFD 1D codes 2010 2015 2020 Trends • Increased processor speed and algorithm improvements lead to speed-up of factor 1000 per decade in CFD codes • Demand for more accurate physical modelling leads to slow down of current 1D and future 2D simulators • Pre-integrated models (use of turbulent velocity field information)
Naive application of CFD • CFD simulation of 2-phase system • 30m pipe, 2x104 cells requires 5 days CPU time (4 processors) to simulate 30 second real time • Field case • 5km pipe, 1hr transport time • 3x106 cells, 95040 days of simulation time • With speed-up factor of 1000/decade it becomes possible to perform real-time 3D transient simulation of 5km pipe within 20 years
FACE Horizon/LEDA Physical complexity Industry 101 107 105 103 L/D Multiphase research in Norway • Research is driven by industry and institutes • Academic activity is scattered • Who is doing the really difficult ground work? • Where are the future researchers being educated?
Intelligent CFD • Massively parallel simulations • Use information from 1D/quasi-1D/2D codes as pre-conditioners for 3D solution • Multi-scale simulator • Decouple high-frequency/short-length scale effects from low-frequency/long-length scale phenomena