OLGA Standard Engineering Modules

OLGA consists of a number of modules that are separately priced and delivered.

OLGA Basic OLGA Basic includes the steady-state and dynamic network solver for two-phase flow, as well as most process equipment. The user interface is also included in Basic in addition to the OLGA server interface, allowing for interface with other simulators.
Water Module (Three-Phase Flow) The Water Module gives a three-phase capability that allows prediction of separated water together with normal two-phase hydrocarbon fluids. The Water Module was developed to simulate the slip (velocity difference) between oil and water. In almost all cases, production pipelines have three phases flowing simultaneously (gas, oil, and water). At low velocities there is considerable slip between the oil and water phases. As a result, the water tends to accumulate in low spots in the system. This leads to high local accumulations of water and thereby a potential for water slugs. It may also cause serious corrosion problems.
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
PVTsim OLGA incl. Hydrate & Multiflash The PVTsim package from Calsep provides reliable fluid characterization with robust and efficient regression algorithms to match fluid properties and experimental data. The fluid parameters may be exported to produce high quality input data for reservoir, well, pipeline and process simulators.  The basic PVTsim package allows for characterization of fluids based on the fluid composition, flashes to determine fluid properties and generation of phase envelopes. Furthermore, it can be used to generate fluid descriptions to be used both for standard OLGA simulations and for compositional simulations. The multiflash option extends the PVTsim capabilities to include aqueous components and the hydrate option allows for accurate calculation of hydrate formation conditions of gas and oil mixtures. The depression of the hydrate formation temperature by the most commonly used hydrate inhibitors can be simulated (e.g. MeOH, EtOH, MEG, DEG and TEG) as well as the loss of inhibitors to the hydrocarbon phases. If the water contains salts, the influence of these salts on the hydrate formation conditions will also be taken into account.
Corrosion Module Three commonly used CO2 corrosion models are available: de Waard 1993, de Waard 1995 and Norsok M-506. With the Corrosion Module it is possible to predict the variation in corrosion rate along a pipeline where temperature, pressure, flow velocity and flow regime varies. An important benefit is the possibility to identify the locations along the pipeline where it is most likely that corrosion problems may occur. The flow regime prediction from OLGA is used for prediction of oil or water wetting of the pipe wall. Pressure, temperature, liquid flow velocity and wall shear stress calculated by the flow model are used in the corrosion rate calculations. The pH value is calculated for condensed water without corrosion products, for condensed water saturated with iron carbonate and for formation water with specified bicarbonate content.	Typical cases: CO2 corrosion effects Models : De Waard 1993 De Waard 1995 Norsok M-506
FEMtherm Module The FEMtherm Module simulates the thermal interaction among the production flowlines, heating lines and other lines that are enclosed within a bundle. FEMtherm allows for an effective screening of a wide range of bundle geometries and burial configurations. Uses include determining the spatial temperature distribution in pipeline bundle cross sections, investigating the effect of thermal insulation, investigating the heat exchange between pipelines in the same bundle (i.e. when considering pipeline heating during shut-in or prior to start-up) and investigating the temperature field in the soil around buried pipelines.	Typical cases: Bundled pipelines Buried pipelines Complex risers Heating, cooling and heat exchange effects
Multiphase Pump Module The Multiphase Pump Module optimizes multiphase boosting, design and operational analysis. Models for centrifugal and displacement pumps are available. Multiphase boosting can extend field life, give possibilities for development and production of low pressure reservoirs, and may provide enhanced and faster production. The module gives the opportunity to do detailed simulations with centrifugal and displacement pumps. The pump characteristics are defined through pump data tables, which the user can specify. Typical sets of pump characteristics are included in the code if the characteristics of the required pump are unknown. The pump speed and recycle flow can be regulated by controllers. The user can choose the recycle flow to be gas only, liquid mixture, water only or a complete multiphase mixture.	Typical cases: Inclusion of multiphase pumps Centrifugal pump Displacement pump
Advanced Well Module Simulates the transient multiphase flow in the well bore. The Advanced Well Module is designed for well flow applications where the reservoir properties and the inflow relationships will play an important role when modelling the scenarios. The reservoir performance is specified through permeability, extension of the reservoir, fluid properties etc. or from draw-down/build-up tests from the actual well. Drilling simulation is an option that is available through the Advanced Well Module. The drilling option can be used to simulate the thermal-hydraulics in a drilling operation. The drilling option allows for the possibility of injecting fluid (gas lift for example) through concentric annulus or a parasite pipe. A moving grid system is used to simulate the flow along the drilling string in the annulus during drilling.  The module includes a mud phase that may be used as a 4th phase in simulations.	Typical cases: Start-up-shutdown of production Well testing Production from different zones Reservoir injection, e.g. WAG Flow in annulus, gas lift Multilateral well simulations Simulation of flow during drilling Manage pressure drilling profile Blowout simulations
Wax Module The module predicts the requirements for pigging for wax removal, thermal insulation, active heating and chemical injections. The Wax Module in OLGA® is capable of calculating deposition and transport of wax components along the pipeline. Wax deposition due to molecular diffusion occurs on the inside surface of a flowline when the pipe wall temperature falls below the wax appearance temperature (WAT). Wax precipitation will occur in the oil bulk flow when the bulk temperature is below WAT. Dissolution of wax and shear related radial wax transport effects may also be activated by the user. The Wax Module allows the user to tune the fluid properties related to molecular diffusion, shear related wax transport and effective viscosity of an oil-wax mixture. OLGA® also simulates pigging operations for wax layer removal and transport.  Functionality to generate wax tables from PVTsim is included in this module.	Typical cases: Pigging for wax removal Thermal insulation due to wax layer  build-up Active heating Chemical injections
PVTsim Wax PVTsim WAX is a valuable addition to the Wax Module and offers a function (with a separate interface) to tune the waxy fluid to match measurements of  WAT, amount of wax in the oil and viscosities of oil affected by  solid wax.  The interface also provides 3 different PT curves (wax appearance points in a PT –plot, phase envelope neglecting and considering wax). The various plots can be combined to visualize the effects of the wax – from a thermodynamic point of view.