PhD Study : Modelling and simulation of premixed combustion in large-scale confined geometries

Summary

Pressure and thermal effects from large-scale deflagrations in large-scale confined geometries like a tunnel can be extremely hazardous due to the transition of initially laminar premixed combustion to the fast deflagration and potentially through the deflagration-to-detonation transition (DDT) to detonation. The role of various flame front instabilities and combustion acceleration mechanisms, especially in a confined and congested environment, is still not fully understood especially at large scales. Moreover, the interaction and thus the development of different instabilities and mechanisms on deflagration dynamics is not yet clarified.

The Ulster’s multi-phenomena deflagration model is under continuous development during last two decades in different parts of the globe. The model currently accounts for the dependence of burning velocity on changing during combustion pressure and temperature of the unburnt mixture, turbulence generated by flame front itself, turbulence in unburnt mixture, increase of burning rate due to preferential diffusion in stretched curved flamelets in the turbulent flame brush, fractal structure of turbulent flame front, etc.

The model has been under continuous validation against a growing number of large-scale experiments, primarily hydrogen-air deflagrations, DDT and even detonations. It is expected that a candidate will develop the model further using the state-of-the-art in the field and expand the validation domain to the problems of practical importance including deflagrations of non-uniform hydrogen-air mixtures in tunnels or similar confined geometries.

Experimental data on large-scale deflagrations are available for use as validation tests from ongoing projects, e.g. experiments on hydrogen release and deflagration in a large-scale tunnel at Health and Safety Executive test grounds within the H2020 HyTunnel-CS project, as well as previous projects in which Ulster University participated, partners in various European projects, and from literature.

The successful candidate is expected to have a strong background in one of the following disciplines: physics, fluid dynamics, heat and mass transfer, combustion, computational fluid dynamics, safety engineering, etc. Any previous experience of analytical analysis and/or numerical modelling is welcome. The research will be conducted at the HySAFER Centre.

The candidate will focus on CFD modelling and numerical simulations, use relevant software (ANSYS Fluent, FieldView, etc.) and the state-of-the-art computational resources – multi-processor workstations available at HySAFER Centre and HPC facility available within EPSRC KELVIN-2 project. This research will be aligned to HySAFER’s externally funded projects and reported at international conferences.

Publication of results in peer-reviewed journals is expected.

Essential criteria

Applicants should hold, or expect to obtain, a First or Upper Second Class Honours Degree in a subject relevant to the proposed area of study.

We may also consider applications from those who hold equivalent qualifications, for example, a Lower Second Class Honours Degree plus a Master’s Degree with Distinction.

In exceptional circumstances, the University may consider a portfolio of evidence from applicants who have appropriate professional experience which is equivalent to the learning outcomes of an Honours degree in lieu of academic qualifications.

• Clearly defined research proposal detailing background, research questions, aims and methodology

Desirable Criteria

If the University receives a large number of applicants for the project, the following desirable criteria may be applied to shortlist applicants for interview.

• Masters at 65%

Funding and eligibility

This project is funded by:

• SusHY

These fully funded scholarships include a tax-free stipend of £16,909 per annum, subject to satisfactory progress over a 4 year period, tuition fees, and a research budget. These awards are open to home/EU and overseas applicants.