Wellcome Trust Featured PhD Programmes
Imperial College London Featured PhD Programmes
Birkbeck, University of London Featured PhD Programmes
University of Dundee Featured PhD Programmes
The Hong Kong Polytechnic University Featured PhD Programmes

The dynamics of jets in rapidly rotating fluids by computational fluid dynamics (CFD) simulation


Project Description

The movement of electrically conducting liquid inside the core of Earth and other planets is responsible for generating their planetary magnetic fields, yet we know very little about their dynamics, as creating realistic simulations is extremely challenging. This project is focused on creating a new type of numerical model for rotating planetary cores, which uses techniques used extensively elsewhere in fluid dynamics: computational fluid dynamics. Such techniques offer a novel method to study local phenomena such as jets within planetary cores.

Of particular relevance for this project is the recent discovery by the supervisory team (see Livermore et al. (2017)) of a jet within Earth’s core at high latitude, using the latest satellite data. This jet is believed to arise due to the influence of rapid rotation on the movement of the fluid within planetary cores, aligning the flow into structures parallel to the rotation axis. Important dynamics may occur if there is a solid inner core – as there is inside the Earth - dividing the fluid into disconnected regions, because the fluid’s response is to form a jet on the interface. This jet may play an important role in the global dynamics of the Earth’s core (just as the jet-stream does in our atmosphere) and also may act to excite torsional waves, which travel within the core and are magnetically observable.

Although the jet is described by a simplistic theoretical framework, there is currently no numerical model that can simulate its existence or time-dependent dynamics. Most models of the Earth’s core are spherical, and focus on the broad global dynamics. However, in this project, spanning both geophysics and applied mathematics, we will focus attention at the local region at high latitude, investigating how jets and other structures form, and their expected signature within the magnetic field. The work will involve developing new theory and using numerical high-resolution computational fluid dynamics (CFD) supercomputer models of rapidly rotating fluids using both the Nek 5000 software package that is based on spectral elements, and OpenFOAM that is based on finite volumes.

The student will learn the theory of fluids within the Earth’s core, but also how to use CFD packages to produce images (and animations).

Funding Notes

This project is in competition for a 3.5 years EPSRC DTP 2020 Environment scholarship which will include tuition fees (£4,500 for 2019/20), tax-free stipend (£15,009 for 2019/20), and a research training and support grant.

References

Livermore, P. W., Hollerbach, R., & Finlay, C. C. (2017). An accelerating high-latitude jet in Earth’s core. Nature Geoscience, 10(1), 62–68. http://doi.org/10.1038/ngeo2859

Livermore, P. W., & Hollerbach, R. (2012). Successive elimination of shear layers by a hierarchy of constraints in inviscid spherical-shell flows. Journal of Mathematical Physics, 53(7), 073104–19. http://doi.org/10.1063/1.4736990

Schaeffer, N., Jault, D., Nataf, H. C., & Fournier, A. (2017). Turbulent geodynamo simulations: a leap towards Earth’s core. Geophysical Journal International, 211(1), 1–29. http://doi.org/10.1093/gji/ggx265

Hori, K., Jones, C. A., & Teed, R. J. (2015). Slow magnetic Rossby waves in the Earth's core. Geophysical Research Letters, 42(1), 6622–6629. http://doi.org/10.1002/2015GL064733

Codes:
NEK 5000: https://nek5000.mcs.anl.gov/
OpenFOAM http://www.openfoam.com/

Email Now

Insert previous message below for editing? 
You haven’t included a message. Providing a specific message means universities will take your enquiry more seriously and helps them provide the information you need.
Why not add a message here
* required field
Send a copy to me for my own records.

Your enquiry has been emailed successfully





FindAPhD. Copyright 2005-2019
All rights reserved.