The following modules are part of the Standard delivery: |
|
|
OLGA 6 Three-Phase
OLGA 6 Three-Phase is the main module. It includes the Steady-state and Transient network solvers for three phase flow (water, oil and gas). The solvers calculate the slip (velocity difference) between the phases. In almost all cases, production tubes and pipelines have three phases flowing simultaneously and at low velocities there is considerable slip between the gas and liquids and also between oil and water. As a result, the liquids tend to accumulate in low spots in the system. This leads to high local accumulations of liquids and thereby a potential for slugging and surges. Where water accumulates there is also potential for serious corrosion problems as well as hydrate formation.
Dispersions of oil and water are also predicted and dispersion viscosities, which may deviate considerably from the oil-water average viscosities, are either calculated by the default models or according to user given tuning factors.
Modelling of basic process equipment is included. OLGA Server interface allows for connecting with other simulators. |
|
|
Slugtracking Module
The Slugtracking Module has a unique feature of tracking each individual slug from its formation to either its exit from the pipeline or its extinction. The model considers the mechanisms of slug formation, the merging of slugs, growth and decay of slugs. The Slugtracking Module has considerable value in the design of production facilities. It is designed to determine whether downstream equipment (such as separators and compressors) will be capable of processing the slugs properly. The mechanisms of slugging that are included are hydrodynamic, terrain, start-up, rate change induced and slugging generated from pigging. |
Typical cases:
- Control strategies and system design
- Operational procedures/guidelines
- Pigging procedures
- Slug catcher & separator design
- Operational trouble shooting
|
|
Compositional Tracking Module
The Compositional Tracking Module allows dynamic change in fluid composition and tracking of individual components along the pipeline. In OLGA Basic the chemical compositions are defined as constant throughout a simulation. In reality, the composition may vary along the pipeline due to slip effects (velocity differences between phases), interfacial mass transfer, merging networks with different fluids and changes in fluid composition at the inlet. In the compositional model, mass equations are solved for each component in the gas phase, droplets, bulk of the oil and water phases. Thus, the compositional model will keep track of the changes in composition in time and space, and ensure a more correct fluid description compared to the basic OLGA model. |
Typical cases:
- Merging network with different fluids
- Shut-in and start-up scenarios
- Gas injection and gas lift
- Changes in composition at inlets and in sources
- Tracking of gas quality
- Blow-down
- Safety analysis
|
|