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Comparison Report PIPENET 1. Can be used only for pure liquids 2. Both Transient & Steady State Runs can be made. Although transient analysis requires a dedicated license to access transient operation features. Current version of PIPENET used at Snamprogetti, Fano office is V. 1.3.2 3. Pipe sizing using Pipenet can be applied only to single phase lines. 4. Surge Analysis is a feature for estimating surge pressures & necessary surge equipment for liquid lines during liquid hammer situations. These problems are transient & are generally part of engineering work in oil & water pipeline jobs. For pump calculations, the inertia of both pump rotor & driver rotor are taken into account during calculations. Pump modelling using pump curves are available & play an important role in transient calculations to calculate shut-off pressure. 5. Piping schedules & mechanical properties such as Young's Modulus, etc are provided for commonly known standards such as ANSI & ASME as a built-in feature of the software. These are used for calculating speed of sound in pipelines during transient operations such as ESD failure, pump failure, etc. 6. Pre-built functions such as Step, Ramp, Impulse functions are available. These are used to simulate situations such as valve operations such as on-off, quick opening, etc. 7. Flow problems involving hydrate, wax deposition, etc cannot be solved. 8. Pipe fittings data are readily available providing loss coefficient to predict losses across bends, tee's etc. Piping elements such as nozzles, orifice plates, dampers, control valves, filters etc are available to accurately model a pipe network. 9. A sprinkler module is available to simulate fire protection systems.

OLGA 1. Can be used for Multiphase flow modelling. 2. It must be noted that OLGA is only a solver & does not provide fluid properties as part of its package. For example, HYSYS has an inbuilt fluid property package estimator providing EOS (PR, SRK), Activity models, ASME Steam Tables, etc. To obtain such properties another commercially available package called PVTSIM is mandatory since the fluid properties are estimated first with PVTSIM & are then exported as a table file to OLGA. Hence PVTSIM is also necessarily to be purchased since it is used for creating fluid properties for both OLGA multiphase calculation as well as compositional tracking. The additional features which are used for real time Oil & Gas projects involve generating phase envelopes for multiphase systems as well as hydrate curves & hydrate inhibitor dosages. 3. OLGA's basic capabilities involve multiphase flow calculations, compositional tracking module to estimate composition of individual components of a hydrocarbon stream along the pipeline & slug tracking module to estimate slugging phenomenon. Currently available configurations are a. OLGA standard - contains above mentioned three basic modules b. OLGA professional - To predict corrosion rates, wax deposition, multiphase pump usage, hydrate kinetics, Inhibitor tracking, etc. This is the configuration available at Snamprogetti, Fano office & is considered as a minimum configuration to carry out real time Oil & Gas projects. c. OLGA for Wells - Involves a Well module for well modelling For more details refer http://www.sptgroup.com/en/Products/olga/olga-product-capabilities/

4. Both steady state & transient analysis can be performed without the need for a dedicated transient license. Pipe sizing using OLGA can be extended to multiphase lines. 5. Heat transfer calculations for both above ground pipes & buried pipelines are very precise taking into account soil properties, piping material properties, etc. 6. Wax deposition module is available. This module is used to estimate the wax deposition rates for different kinds of oils such as paraffinic bases, etc. 7. Slugging phenomena can be modelled accurately using OLGA. Currently OLGA2000 is the only software with capabilities to estimate not only hydrodynamic slugging but also provides slug tracking module to predict terrain induced slugs, start-up, ramp-up & shutdown slugs, etc in risers & similar equipment. This dictates accurate slug catcher sizing. In fact, OLGA is the industry standard towards solving transient problems such as pipeline pigging, slugging, start-up, shutdown, ramp-up operations, etc. 8. Features such as compressors, multiphase pumps & controllers are also available. This aids in performing studies to determine all possible operating scenarios during FEED when it is necessary to determine if a multiphase pump or a single phase pump is required & the effects of each of these on one another during process upsets. 9. Pipeline pigging operations can be simulated using OLGA. 10. Orifice sizing for Multiphase flow using OLGA is very accurate & this was demonstrated in the BS160 project wherein which, the burn pit orifice was sized for multiphase flow. 11. Limitations exist in the following manner a. Fast transient such as shock wave emerging from a pipe rupture, etc, cannot be modelled accurately. This is so since it is a one dimensional solver & domain discretization features are limited by Courant Freidrich Lowry (CFL) conditions. b. Prediction of pressure drops for water lines as they are found to be erroneous on some occasions. This is based on Snamprogetti, Fano experience. c.

Hydrate check facility though available cannot be relied upon. This is assumed since OLGA v.5.2 provides a module for Hydrate calculations but was subsequently removed in the next version of OLGA v.5.3. Current version of OLGA available in the market is V.6.3 which needs to be investigated & also validated. Usage of old version requires the need to use hand calculations to verify OLGA results.

d. Flow elements such as orifices, nozzles, etc are not available but can still be solved with good accuracy by declaring these elements as an equivalent valve. This was demonstrated in the BS160 Burn pit header orifice sizing