Fluid Mechanics Seminar: Duncan R. Hewitt

  • Date: 09/11/2014
  • Time: 16:00

Duncan R. Hewitt, UBC


Duncan Hewitt is a Killam Postdoctoral Fellow and PIMS Postdoctoral Fellow in the Department of Mathematics at UBC. He received a Ph.D. in 2014 from the Department of Applied Mathematics and Theoretical Physics, University of Cambridge, UK, having studied under the supervision of John Lister and Jerome Neufeld. His doctoral research was in the subject of convection in porous media. He has also worked on non-Newtonian flows, two-phase flows, and poro-elasticity.



University of British Columbia


High Rayleigh number convection in porous media.


Convective flow in porous media can be found in numerous geophysical and industrial processes, and has recently been investigated in the context of geological CO_2 sequestration. I will present high-resolution numerical simulations of statistically steady high-Rayleigh-number convection in a porous medium that is heated at the base and cooled at the upper surface. I will discuss the relationship between the strength of convection, as described by the Rayleigh number, and the transfer of buoyancy, as described by the Nusselt number. I will examine the remarkable dynamical structure of high-Rayleigh-number porous convection: the structure is characterized in the interior by ordered vertical columnar exchange flow with a regular (Rayleigh-number dependent) horizontal wavenumber k(Ra), and near the boundaries by vigorous short-wavelength boundary-layer instabilities . I will investigate the physical control of this structure by performing a stability analysis of the interior columnar flow: the predictions of this analysis give good agreement with the measured horizontal wavenumber k(Ra). Numerical results will be presented in both two-dimensional and three-dimensional porous media.

I will then extend these results to consider the more physically relevant context of convection from below one boundary only, and consider the implications of these results for the long-term storage capacity of underground water-saturated porous rocks into which CO_2 has been injected.

Other Information: 

Location: ESB 2012