PE Distinguished Seminar Series: Interaction Between Proppant Compaction and Single/Multiphase Flows in a Hydraulic Fracture
October 19 @ 10:00 am - 11:00 am
Cheng Chen, Ph.D.
Pore-scale Imaging/Modeling and the Application in the Study of Proppant Compaction and Embedment
Understanding of proppant transport and deposition patterns in a hydraulic fracture is critical for effective and economical production of hydrocarbons. In this research, a numerical modeling approach, combining the discrete element method (DEM) with single-/multiphase lattice Boltzmann (LB) simulation, was adopted to advance the understanding of the interaction between proppant compaction, embedment, and single-/multiphase flows in a hydraulic fracture. DEM was used to simulate effective stress increase and the resultant proppant particle movement and rearrangement during the process of reservoir depletion. Simulated pore structure of the proppant pack was extracted and used as internal boundary conditions in the LB flow modeling to measure the time-dependent permeability of the proppant pack. Three proppant packs with the same average particle diameter but different diameter distributions were generated to study the role of proppant size heterogeneity (variation in particle diameter). Specifically, we used the coefficient of variation (COV) of diameter, defined as the ratio of standard deviation of diameter to mean diameter, to characterize the heterogeneity of particle size. Proppant embedment into rock formations was determined using an empirical equation obtained by fitting experimental data. In order to validate the numerical workflow, proppant pack conductivity as a function of increasing proppant concentration was simulated and then compared with laboratory data. Good agreement was observed between the DEM/LB-simulated and laboratory-measured fracture conductivity versus proppant concentration curves. Furthermore, the role of proppant size, size heterogeneity, and closure pressure on the optimal partial-monolayer proppant concentration was investigated. The results of this research provide fundamental insights into the factors regulating the conductivity evolution of a proppant-supported fracture. These findings advance the fundamental understanding and have important implications to optimization of proppant placement, completion design, and well production.
Bio: Dr. Cheng Chen is an assistant professor in the Department of Mining and Minerals Engineering at Virginia Tech. He is holding a part-time faculty researcher position with DOE’s National Energy Technology Laboratory and is currently serving as an Associate Editor of SPE Journal. Prior to joining VT, he was a reservoir engineer and project leader at Halliburton Houston. Dr. Chen’s research is focused primarily on advanced numerical methods in porous media, multiscale simulation of subsurface flow and transport, rock characterization with high-resolution CT and SEM imaging, and the applications to shale oil and gas recovery, geologic carbon sequestration, and water resources. Dr. Chen earned his bachelor’s degree in hydraulic engineering from Tsinghua University, China, and doctoral degree in civil and environmental engineering from Northwestern University.