An area of difficulty in oil and gas exploration is in determining the production of a gas field. A section view of such a field is shown in Figure 1. It was originally published on Wikipedia. The gas is often trapped in small pockets deep below the earth’s surface. Hydraulic fracturing is used in these fields to connect the small gas pockets together. Water is pumped into the well and is pressurized to the point so that it creates small cracks that form a network between the pockets. The network emanates from the drill bore to a finite extent in the surrounding gas field. I was reading this interesting article on the Shell Corporation website last week and thought a very good tool that could be used to both characterize the performance of a fracturing operation and predict the performance of future fracturing operations is Autodesk CFD 2016.
Figure 1. Section view of a tight gas field
I found the work described by Tsai (1) to be interesting. The researcher is successfully deploying a computational fluid dynamics tool to gain insight into a flow field that is very difficult to quantify using experimental techniques alone. Instead, Tsai is exploiting the dual Eulerain/Lagrangian features of CFD to understand the behavior of the slurry. They are interested in injecting small particles, proppants, to help keep the cracks created by the hydraulic fracturing operation open.
I had a similar challenge to address and found the motion module within Autodesk CFD to be robust and easy to use. The path to solving this problem would be a little different in that instead of using a specialized tool that is run by an expert analyst, the Autodesk CFD path would involve a more general engineer and usage of a CFD tool that is easy to use. This path also allows access to a highly trained team of fluid mechanicians that can assist in the problem development so that the opportunity for success is maximized.
The importance of leaving as little natural gas as possible in the field is important for economic reasons. Computational fluid dynamics offers businesses who are interested in oil and gas exploration another tool to help achieve this goal. Autodesk CFD 2016 already contains many of the extra attributes that are required to successfully model the proppant distribution problem. As a result, the tool can greatly help in arriving at an informative solution.
(1) Tsai,K., “CFD Modeling of Proppant Transport in Tight Gas Fractures and Strategies for Production”, Proceeding of the 2014 American Institute of Chemical Engineers Annual Meeting, Particle Technology Forum