Most of the Flow Assurance studies performed in-house are devoted to the early design of new fields, in which the main issues are identified and the recommended field architecture and operating philosophies are defined. Such early design stages are characterized by the occurrence of significant changes along the course of the studies, as long as new information becomes available. For example, production profiles or well positioning and line routing can change; or early-production phases, with limited flowrates, may be introduced, etc. Such changes are particularly frequent in fast-track engineering, where several studies are parallelized, and this fact gives to the Flow Assurance specialists the additional task to understand as quickly as possible the implications of each change and help finding the best development options. The above situation typically requires continuous rework and the review of previous decisions with modified constraints. In this context, to increase the internal productivity and the robustness of Flow Assurance studies, we have internally developed a tool to support the Flow Assurance workflow. Such tool is based on the following components:
a High Performance Computing facility to run the simulations, endowed with a scheduler to optimize the usage of software licenses and hardware resources;
an innovative post-processing system, conceived to facilitate the extraction of the relevant information from the simulations (which we call Key Engineering Variables) and document the adopted decisions;
a fully browser-based interface, to explore the simulations, examine the effect of the design constraints and launch new simulations, even from tablets without any specialized software and
a new Field Model description, from which simulation input files can be automatically generated, built with the purpose to easily apply changes, to follow the evolution of the field architecture from the early phase to the as-built stage and to store the information for several years, being tabular and independent from ever-changing simulator input formats.
The Field Model structure will be described elsewhere, while this paper relates to the other points.
The system has been developed along the past two years and has been in use, as a prototype, for several months during which improvements in the architecture and the interface were carried out. The main conclusions of the test phase, which led to the first stable version, are the following:
Flow Assurance decision making was faster than before and could sometimes be discussed during interactive team-work, by leveraging on the innovative browser-based tools
re-work became less labour-intensive and faster, leading to improved change-management and facilitating critical thinking
the quality of the simulations could be assessed more pervasively, allowing faster debugging and achieving better technical results
engineering analyses became more standardized and explicit, facilitating team alignment and tracking of previous reasoning
the Field Model description, being able to accommodate both as-built geographic information and design assumptions, allowed to speed-up expansion studies of existing fields, where several new wells had to be integrated into existing gathering networks.
The paper will describe the system, which has been called e-fast™ (eni Flow Assurance Simulation Toolbox), in the light of the above experiences.
