Bath Numerical Analysis seminar - upcoming
Fridays at 12.15 at Wolfson 4W 1.7. All talks will be broadcast on Zoom.
Everyone is welcome at these talks.
| Date | Speaker | Title |
| 7 Feb 2025 | Andreas Kyprianou (University of Warwick) |
TBC
TBC |
| 14 Feb 2025 | Colin Cotter (Imperial College London) |
TBC
TBC |
| 21 Feb 2025 | Eike Mueller (University of Bath) |
High-order IMEX-HDG timestepping methods for the incompressible Euler equations
Discretisation methods that are of high order in space and time are highly desirable when solving the equations of fluid dynamics since they show superlinear convergence and make efficient use of modern computer hardware. We develop an efficient timestepping method for the incompressible Euler equations based on combining implicit-explicit (IMEX) time-integrators, high-order Hybridised Discontinuous Galerkin (HDG) discretisations and splitting methods. The two computational bottlenecks are the calculation of a tentative velocity and the solution of a velocity-pressure system to enforce incompressibility. The second solve is preconditioned with a non-nested hybridised multigrid preconditioner as proposed by Cockburn, Dubois, Gopalakrishnan and Tan for the Schur-complement system that arises from static condensation to eliminate the pressure/velocity unknowns in favour of variables on the mesh-facets. The tentative velocity solve is preconditioned with ILU0. With this choice of preconditioners, the number of solver iterations depends only weakly on the polynomial degree and the grid-spacing; in other words, empirically the method is approximately h- and p-robust. As a consequence, the cost of a single timestep is roughly proportional to the total number of unknowns. At high order this allows the computation of highly accurate solutions at a low computational cost. The code has been implemented in Firedrake, using static condensation technology and PETSc to construct a fairly complex solver/preconditioner. Numerical results are presented for the simulation of a two-dimensional Taylor-Green vertex. |
| 21 Feb 2025 | Sam McCallum (University of Bath) |
TBC
TBC |
| 28 Feb 2025 | Henry Lockyer (University of Bath) |
TBC
TBC |
| 28 Feb 2025 |
TBC |
TBC
TBC |
| 7 Mar 2025 | Eric Hester (University of Bath) |
TBC
TBC |
| 7 Mar 2025 | Michael Murray (University of Bath) |
TBC
TBC |
| 14 Mar 2025 | Sam Flynn (National Physical Laboratory) |
TBC
TBC |
| 21 Mar 2025 | Jemma Shipton (University of Exeter) |
TBC
TBC |
| 28 Mar 2025 | Poppy Nikou (UCL Hospitals NHS Foundation Trust) |
TBC
TBC |
| 28 Mar 2025 | Mathew Southerby (UCL Hospitals NHS Foundation Trust) |
TBC
TBC |
| 4 Apr 2025 | Cristopher Salvi (Imperial College London) |
TBC
TBC |
| 4 Apr 2025 | Maud Lemercier (University of Oxford) |
TBC
TBC |
| 25 Apr 2025 | Ben Tapley (SINTEF, AI and Analytics group) |
TBC
TBC |
| 2 May 2025 | Patrick Fahy (University of Bath) |
TBC
TBC |
| 2 May 2025 | Max Scott (University of Bath) |
TBC
TBC |
Subscribe to seminar calendar
You can subscribe to the NA calendar directly from your calendar client, including Outlook, Apple’s iCalendar or Google calendar. The web address of the calendar is this ICS link which you will need to copy.
To subscribe to a calendar in Outlook:
- In Calendar view, select “Add Calendar” (large green +)
- Select “From Internet”
- Copy paste the ICS link, click OK, and click Yes to subscribe.
To subscribe to a calendar in iCalendar, please follow these instructions. Copy paste the ICS link in “web address”.
To subscribe to a calendar in Google Calendar:
- Go to link.
- On the left side go to "Other Calendars" and click on the dropdown.
- Choose "Add by URL".
- Copy paste the ICS link in the URL of the calendar.
- Click on "Add Calendar" and wait for Google to import your events. This creates a calendar with a somewhat unreadable name.
- To give a readable name to the calendar, click on the three vertical dots sign next to the newly created calendar and select Settings.
- Choose a name for the calendar, eg. Numerical Analysis @ Bath, and click back button on top left.
How to get to Bath
See here for instructions how to get to Bath. Please email James Foster (jmf68@bath.ac.uk) and Aaron Pim (arp46@bath.ac.uk) if you intend to come by car and require a parking permit for Bath University Campus for the day.Tips for giving talks
Tips for new students on giving talks
Since the audience of the NA seminar contains both PhD students and staff with quite wide interests and backgrounds, the following are some guidelines/hints to make sure people don't give you evil looks at lunch afterwards.
Before too much time passes in your talk, ideally the audience should know the answers to the following 4 questions:
- What is the problem you're considering?
- Why do you find this interesting?
- What has been done before on this problem/what's the background?
- What is your approach/what are you going to talk about?
There are lots of different ways to communicate this information. One way, if you're doing a slide show, could be for the first 4 slides to cover these 4 questions; although in this case you may want to revisit these points later on in the talk (e.g. to give more detail).
Remember:
- "vertebrate style" (structure hidden inside - like the skeleton of a vertebrate) = good for detective stories, bad for maths talks.
- "crustacean style" (structure visible from outside - like the skeleton of a crustacean) = bad for detective stories, good for maths talks.