Dynaflow Research Group is capable of assisting well operators and manufactures for well equipment in the design and validation of techniques used for well operations/procedures. Using (validated) Computational Fluid Dynamic (CFD) techniques to simulate behavior of flow inside wells at a high resolution allows for an understanding of the flow’s behavior that is difficult to obtain through measurements inside the wells itself.
Dynaflow has assisted its clients for several types of flow studies inside wells. Below is a selection of these projects briefly explained.
- Increasing sealing efficiency of well abandonment methods through CFD.
- Force prediction and optimization of novel directional drilling tool.
Increasing sealing efficiency of well abandonment methods through CFD
Several operators are currently or have been decommissioning wells in the North Sea fields that were drilled in the 1980’s. Part of the well decommissioning is plugging or sealing-off the wells to prevent leakage from the reservoir into the environment after decommissioning.
Sealing-off the well can be achieved using various methods. The success of the method depends on factors such as location of placement, operating procedure used, fluid used to seal the well and specific well parameters. Difficulty in predicting the sealing performance of a specific method is a result of the limited access wells provide to verify sealing performance.
In order to better predict sealing performance, the client has required Dynaflow Research Group to use computational methods in order to predict displacement efficiency of a fluid-fluid displacement method used to seal the wells. Various existing and hypothetical wells were simulated to both validate the simulations and be able to identify critical parameters that influence displacement efficiency. The simulations were conducted using a 3-D multiphase solver, simulating the complete to-be displaced domain of the wells. Effects including fluid rheology (non-linear viscosity), density, and well inclination were accounted for as well as other effects.
Results of the study were the validation of the computational method and the identification of parameters critical for a good displacement efficiency. Client was able to use these results to verify proposition made by contractors for sealing procedures. Furthermore, the client was able to adjust standard sealing procedure to ensure critical fluid parameters were met within a given tolerance.
Force prediction and optimization of novel directional drilling tool
Client was working on a novel tool used for directional drilling and was able to successfully create a proof of concept through in-house, small scale experiments. However, for the tool to become competitive, further improvements needed to be made many in increasing the lateral force created on the drill string.
The first step of the project was to replicate the initial experiments by simulation and validate the computational methods. This provided insight in the flow mechanisms that generate the forces and that allowed for specific changes to the design to optimize the performance.
The second step was to simulate the newly proposed design changes and predict the performance of the tool. Several designs were explored considering not only the geometry of the tool but also varying flow conditions used. This enabled the design of a high performing and all-rounded tool.
Using the result of this project, the Client was able to finalize the design of the tool and was able to market the new tool as a competitive alternative to existing directional drilling tools.