Room 315 Marquez Hall
Golden, CO 80401 USA
Office: (303) 384-2449
Fax: (303) 273-3189
PhD, Chemical Engineering, Cornell University, 2006
MS, Mechanical Engineering, Lehigh University, 2001
BS, Theoretical & Applied Mechanics, Beijing University, 1999
Suspension, multiphase flow, transport and reactions in porous media, EOR processes.
Dynamics of binary gas-solid and liquid-solid suspensions
Suspensions of solid particles are involved in many natural and industrial processes. The rheological properties of a suspension containing only one type of particles (monodisperse) are relatively well known. The dynamics of binary suspensions that contain particles of different sizes or densities is much more complex than that of a monodisperse suspension, and many basic properties that are critical for continuum-scale modeling (Euler-Euler or Euler-Lagrange), such as fluid-particle drag, particle-particle drag, have not been studied in detail. In this project, direct numerical simulations are used to study the sedimentation of binary gas-solid and liquid-solid suspensions. We characterize, in particular, rate of sedimentation, microstructure, frequency of collision, and instability patterns for different combinations of particle sizes, densities, and concentrations. These properties are of fundamental value for the understanding and correct modeling of binary suspensions.
Simulation of single- and two-phase flows in 2D/3D computer-generated random porous medium
Flows in porous media involve multiple length and time scales. Good understanding of the flow and transport on the small scale is critical for establishing accurate continuum models. We construct numerical two- and three-dimensional porous media geometry models made by randomly oriented and interconnected micro-channels, fractures, or fibers. These porous media models can be used to study flow, transport, and reaction in nanoporous materials where the geometry of the medium cannot be obtained easily via conventional X-ray tomography techniques. We will use lattice Boltzmann simulations to study single-phase and multiphase flows in these porous media analogs. Current research focuses on transition to non-Darcy (Forchheimer) flow, Klinkenberg (slip) flows, and two-phase displacement flows.
Numerical modeling of CO2 sequestration in saline aquifers
CO2 geological sequestration is considered to be a viable solution to mitigate the emission of large quantities of CO2 into the atmosphere and alleviate the green house effect and global warming. Among all sequestration options, saline aquifers have the largest capacity for the storage of CO2. CO2 geological sequestration involves many complex physical and chemical processes. Supported by US Department of Energy, I am working with Professor Yu-Shu Wu and other faculty members of MCERS as well as scientists in Lawrence-Berkeley National Laboratory to develop a comprehensive numerical simulator to study the non-isothermal, multiphase flow in heterogeneous porous media, with geomechanics, dissolution, and mineral reactions taken into account.
Experimental study of porosity / permeability change induced by change in pore pressure
It is well known that porosity and permeability of rock can vary with pore pressure. Many different empirical relations have been derived. We believe that the dependence of porosity / permeability on pressure may give us important information on the microstructure of the rock. In this experimental study, we will test the hypothesis using sand stone and carbonate samples.
Slim tube study of MMP in CO2-EOR applications
Slim tube is a stainless steel tube that has an extreme aspect ratio (60ft long, 1/8 inch ID) that can be subjected to reservoir pressure and temperature. Packed with sand particles, it is a one-dimensional analog of a sandstone reservoir, and is used as the industry standard for minimum miscibility pressure (MMP) testing in gas-EOR applications. We use slim tube to study MMP between CO2 and crude oil samples during a displacement process, as well as dissolution of gas in formation brine.