Research:

My research is focused on the dynamics of multiphase systems in geophysical settings using analytical, numerical and experimental techniques.  I am exploring the solidification of binary solutions as found in the polar oceans when salt water freezes and in the Earth’s core, as well as the geological sequestration of carbon dioxide, an important greenhouse gas.  Below are some of the current research projects which I am involved in.

Carbon dioxide sequestration:

Concern for the long-term fate of the Earth’s climate has increased in recent years with many studies linking the increased atmospheric concentrations of carbon dioxide (CO2) with the rise in global mean annual temperature.  One route to significant reductions in the CO2 emissions from stationary sources, such as power plants, is the capture and storage of large volumes of CO2 in the subsurface: so-called geological carbon sequestration.  My research in this area has focused both on mechanisms for stable long term sequestrations, as well as assessing the form of any possible leakage back to the surface.

Convective dissolution.  Stable long term sequestration may be possible through a sequence of secondary mechanisms such as the convective dissolution of CO2 into the ambient brine.  Dissolution of CO2 will create a dense, CO2 saturated brine which is convectively unstable and therefore sinks to the bottom of the reservoir were CO2 is thus stably stored.  Using a novel experimental analogue, a mixture of methanol and ethylene-glycol (MEG) we are able to simulate the dissolution of the buoyant species (here MEG) into the dense ambient fluid resulting in convective dissolution.  Our experiments have constrained the flux as a function of the characteristic parameters of the system and thus enable us to estimate the effect of convective dissolution on CO2 sequestration. (click the image for a movie)

Leakage through fissures and pipes.

  Sequestration of buoyant CO2 must initially be done in location for which an impermeable ‘cap rock’ blocks ascent back to the surface.  If such currents encounter either a fracture or fissure through which CO2 can leak the efficiency of storage, defined as the ratio of fluid permanently stored to that which leaks, will decline as a function of time.  We have characterised the magnitude of leakage in both two dimensions and for radially spreading currents.  These numerical and analytical calculations have been complemented by series of analogue experiments in which dense fluid spread in a Hele-Shaw cell (as shown above).

Melting icicles  The evolution of

an icicle couples convective flow of (cold) air around its surface with the evolution of the free surface.  We have modelled cold boundary layer which flows over the melting icicle, and which dominates the evolution of its shape.  These ideas are currently being extended to examine dendritic solidification and the growth and form of icicles found commonly in nature.

Growth of sea ice and oceanic currents  The formation of sea ice in the polar regions influences, and is influenced by, oceanic currents beneath it.  The lattice

of pure ice crystals which form as the ocean is solidified expel salt, thus creating a dense brine.  As oceanic currents pass under growing sea ice this brine can be coaxed from within the sea ice and, as it passes to the ocean beneath, leaves it’s mark as a series of undulating valleys or crevasses.  We have explored the formation of these features both theoretically and experimentally in the laboratory.  

Papers:

1. •Madeleine J. Golding, Jerome A. Neufeld, Marc A. Hesse, Herbert E. Huppert. (in press) Two-phase gravity currents in porous media.
   

2. •Pawel J. Zimoch, Jerome A. Neufeld, Dominic Vella. (in press) The effect of a fissure on storage in inclined porous reservoirs. (pdf)
   

3. •Dominic Vella, Jerome A. Neufeld, Herbert E. Huppert, John R. Lister. (2011) Leakage from gravity currents in a porous medium. Part II. A line sink. J. Fluid Mech. 666, 414-427. (pdf)
   

4. •Jerome A. Neufeld, Dominic Vella, Herbert E. Huppert, John R. Lister. (2011) Leakage from gravity currents in a porous medium. Part I. A localized sink. J. Fluid Mech. 666, 391-413. (pdf)
   

5. •Jerome A. Neufeld, J. S. Wettlaufer. (2011) Shear flow, phase change and matched asymptotic expansions: pattern formation in mushy layers. Physica D, 240, 140-149. (pdf)
   

6. •Jerome A. Neufeld, Marc A. Hesse, Amir Riaz, Mark A. Hallworth, Hamdi A. Tchelepi, Herbert E. Huppert (2010) Convective dissolution of carbon dioxide in saline aquifers. Geophys. Res. Lett. 37, L22404, doi:10.1029/2010GL044728. (pdf)
   

7. •Jerome A. Neufeld, Raymond E. Goldstein, M. Grae Worster. (2010) On the mechanisms of icicle evolution. J. Fluid Mech. 647, 287-308. (pdf)
   

8. •Jerome A. Neufeld, Dominic Vella, Herbert E. Huppert. (2009) The effect of a fissure on storage in a porous medium. J. Fluid Mech. 639, 239-259. (pdf)
   

9. •Jerome A. Neufeld, Herbert E. Huppert. (2009) Modelling carbon dioxide sequestration in layered strata. J. Fluid Mech. 625, 353-370. (pdf)
   

10. •Melissa J. Spannuth, Jerome A. Neufeld, J. S. Wettlaufer, M. Grae Worster. (2009) Axisymmetric gravity currents flowing over a porous medium. J. Fluid Mech. 622, 135-144. (pdf)
    

11. •M. J. Leahy, J. Ennis-King, J. Hammond, H. E. Huppert, J. Neufeld. (2009) Application of gravity currents to the migration of CO2 in heterogeneous saline formations. Energy Procedia. 1, 3331-3338. (pdf)
    

12. •Jerome A. Neufeld, J. S. Wettlaufer. (2008) An experimental study of shear-enhanced convection in a mushy layer. J. Fluid Mech. 612, 363-385. (pdf)
    

13. •Jerome A. Neufeld, J. S. Wettlaufer. (2008) Shear-enhanced convection in a mushy layer. J. Fluid Mech. 612, 363-385. (pdf)
    

14. •J. A. Neufeld, J. S. Wettlaufer, D. L. Feltham, M. G. Worster (2006) Corrigendum to ‘Flow induced morphological instability of a mushy layer (D. L. Feltham & M. G. Worster, J. Fluid Mech. 391, 337-357)’ J. Fluid Mech. 549, 442-443. (pdf)

Teaching:

I am currently lecturing half of the Part III course in applied mathematics on the Solidification of Fluids with Prof. M. Grae Worster.