Problems with model-based Leak Detection Systems
Model Based LDS have particular problems associated with the real-life process.
Model-based leak detection need to be very accurate: if no tuning is carried out, this means a 1% to 5% errors in packing rate during transients due to physical changes. An inaccurate transient state means look-ahead models will be unreliable. There are many reasons for such inaccuracies:
- Nobody really knows the pipe roughness
- Fluid properties may differ from specifications
- Small impurities can cause large viscosity changes in some liquids
- Effects of DRA
- Liquid holdup in gas pipelines
- Ground temperature near the pipe
- Ground thermal conductivity
- Manually input fluid properties
- Manually input telemetry
- Model deficiencies
Even a fancy method of automatic tuning won’t be able to get a perfect match with all data. The fundamental question is: if there is no “right” answer, do model-based leak detection systems methods prefer good answers to bad ones?
To know more click onto the link below
Automatic Tuning of Pipeline Models, Dr Jason Modisette, Atmos International, presentation for PSIG. Download: [pdf], [zipped]
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