Back to search

PETROMAKS2-Stort program petroleum

Slug Field Model: The Next Generation Field Scale Slug Flow Simulator

Alternative title: Slug Field: neste generasjons simulator for slugstrømning

Awarded: NOK 7.6 mill.

In this project, Schlumberger and IFE aim to invent the next generation simulator to capture the slug flow evolution in oil and gas pipelines. We aim to develop a novel modeling approach by coupling a new slug evolution model with the conservation equations of slug flow. This approach will enable time efficient simulation of developing slug flow. Innovations in multiphase technology have enabled safe, environmentally sound, and economic hydrocarbon production from remote and deep offshore reservoirs. Simulators, such as OLGA, have significantly improved the industrial capability to manage multiphase flow in oil and gas production. In 2012, Aftenposten recognized OLGA as "the most important Norwegian innovation since 1980", noting its role in enabling 40-50 billion NOK saving on Troll field development alone. The model in this project, called the Slug Field model, will be implemented in OLGA upon validation with field data. The new model is expected to produce an unprecedented combination of speed, accuracy and functionality for the multiphase simulation technology, which will enable more safe, robust, and sustainable oil and gas development in the future. Slug flow is a very common flow regime in oil and gas production. In slug flow, liquid slugs and large gas pockets flow alternately. Due to the flow development, slugs in long pipes can grow much longer than those in short pipes. These long slugs may lead to issues such as overfilling of vessel and equipment damage. These issues are more critical for long pipelines in the field, which provide greater distance for flow development. Moreover, slug development is very difficult to predict. The most commonly used slug flow model, called the Unit Cell Model, assumes no flow development and is mostly tuned to short pipe data. Therefore, it is not suitable for long distance pipeline simulations, which are common in Norwegian Continental Shelf. More complicated models, such as Slug Tracking in OLGA, can be used to simulate slug development. However, they are time consuming to run, which often hinders efficient and comprehensive engineering studies. A Slug Field prototype has been developed. This prototype can already be used to demonstrate a speed-up and accuracy gain that is expected to be further enhanced in the final simulator.

-

In this project, SLB and IFE aim to invent the next generation flow model to simulate spatially developing slug flow in long pipelines, with unprecedented computational speed and accuracy. Dynamic multiphase flow conservation equations will be coupled with a novel slug evolution model to achieve this purpose. In multiphase flow, gas and liquid can exist in various arrangements, or flow regimes. Slug flow is a very common flow regime in oil and gas production, especially in mature fields, as well as in CO2 transport systems. It features alternating liquid slugs and gas pockets. Slug flow tends to evolve dramatically throughout pipelines. For example, liquid slugs in long and large pipes can grow to far greater lengths than those in short pipes, leading to operational risks such as separator flooding. This behavior poses significant challenges for long pipeline operations which allow more slug development. Slug developments are very difficult to predict. The most common slug flow modeling technique (unit cell model) assumes no spatial development and is mostly tuned to laboratory data from short pipes. Thus, extrapolating this model to field applications may introduce large uncertainty. There are more exhaustive models that can predict the slug flow development. However, they are computationally much slower than the unit cell model and often impractical for field applications. The enhanced functionality, accuracy, and speed of the new model, called the Slug Field model, will make it suitable for long distance multiphase pipelines, such as many of the subsea lines on the Norwegian Continental Shelf. The model can help operators to reduce uncertainties, leading to more efficient, safe, and environmentally friendly operations. This model will be embedded into the OLGA multiphase simulator. Expertise and data from the OVIP JIP will be leveraged for technology qualification, assuring impactful innovation.

Publications from Cristin

No publications found

No publications found

No publications found

No publications found

Funding scheme:

PETROMAKS2-Stort program petroleum