Events

Dr. Birendra Jha, Postdoctoral Research Associate at MIT, will present a talk entitled "Flow through porous media: from mixing of fluids to triggering of earthquakes" as part of the Claude R. Hocott Graduate Seminar Series.

Bio:
Birendra Jha is a Postdoctoral Research Associate in the Department of Civil and Environmental Engineering at the Massachusetts Institute of Technology where he received his PhD in January 2014. Birendra received his bachelor’s degree in Petroleum Engineering from the Indian School of Mines and his master’s degree in Petroleum Engineering from the Stanford University. Birendra currently works on modeling and simulation of coupled processes of flow, transport, and mechanical deformation in geological porous media, with particular application to reservoir geomechanics and induced seismicity. He has seven years of experience in the oil and gas industry (Schlumberger, Occidental, iReservoir), where he worked on formation evaluation, production optimization, reserves forecasting, geomodeling and reservoir simulation.

Abstract:

In this presentation, I will talk about recent advances on computational modeling of flow through porous media in two different contexts: mixing of fluids of different viscosities, and triggering of earthquakes due to coupling between flow and deformation.

In the first part of the talk, I will discuss enhanced mixing in porous media flows due to miscible viscous fingering, which is the hydrodynamic instability that arises when a less viscous fluid displaces the more viscous one. Based on results from high-resolution numerical simulations, I will present a macroscopic model of mixing that captures the delicate interplay between channeling of less viscous fluid and creation of interfacial area as a result of viscous fingering. The proposed model permits upscaling dissipation due to fingering at unresolved scales. I will show that the synergistic action of viscous fingering and alternating injection can increase mixing efficiency in microfluidic devices by orders of magnitude.

In the second part of the talk, I will discuss the coupling between subsurface flow and geomechanical deformation, which is critical in the assessment of the environmental impacts of groundwater use, underground liquid waste disposal, geologic carbon dioxide storage, and exploitation of shale gas reserves. I will present a new computational approach to model coupled multiphase flow and reservoir geomechanics in the presence of fractures and faults. In this approach, we represent faults as surfaces embedded in a three-dimensional medium by using zero-thickness interface elements to accurately model fault slip under dynamically evolving fluid pressure and fault strength. We incorporate the effect of fluid pressures from multiphase flow in the mechanical stability of faults, and employ a rigorous formulation of nonlinear multiphase geomechanics that is capable of handling strong capillary effects. We develop a numerical simulation tool by coupling a multiphase flow simulator with a mechanics simulator, using the unconditionally stable fixed-stress operator split for the sequential solution of two-way coupling between flow and geomechanics. We validate our modeling approach using test cases that illustrate the onset and evolution of earthquakes from fluid injection and production. We are currently applying our computational model for the study of ground deformations detected from geodetic measurements via GPS and InSAR and for the post mortem analysis of natural or induced earthquakes.