High-pressure hydrogen jet releases, if ignited, can generate not only thermal effects on humans and structures in the form of high-temperature flows and thermal radiation but also hazardous pressure effects (overpressure and impulse). A hydrogen jet released into the air may be ignited immediately, resulting in a jet fire, i.e. non-premixed turbulent combustion, or after some time, resulting in delayed ignition, whereby the combustion of the turbulent premixed hydrogen-air cloud can lead to significant overpressures before a jet fire is formed.
Contemporary tools such as Computational Fluid Dynamics (CFD) and reduced models are needed to predict pressure dynamics and loads which are dependent on the release parameters (pressure and release diameter), jet parameters (free or impinging jet), ignition location and delay in timing of ignition, etc.
Within this study such tools will be developed and validated against available experimental data. Results of CFD simulations can be used to inform the development of predictive engineering correlations. The results of the studies on impinging jets will have a twofold application facilitating the understanding of the potential damage caused but also informing understanding of the mitigation potential of a structure, dependent on whether the jet impinges on a piece of equipment/infrastructure or a barrier. Scenarios involving delayed ignition of turbulent releases in enclosed or congested spaces may be added to the study.
The Ulster multi-phenomena deflagration model with suitable modifications can be employed for the CFD modelling of combustion of the turbulent inhomogeneous hydrogen-air mixture in the jet.
The candidate should undertake coupled CFD-FEM study of hydrogen jet fire effects on structures stability and integrity, e.g. tunnel structures, residential buildings, etc. The outputs from this study will inform guidance for safety engineers, and advance understanding of delayed ignition of hydrogen jets.
Vice Chancellors Research Scholarships (VCRS)
The scholarships will cover tuition fees and a maintenance award of £14,777 per annum for three years (subject to satisfactory academic performance). Applications are invited from UK, European Union and overseas students.
The scholarship will cover tuition fees at the Home rate and a maintenance allowance of £ 14,777 per annum for three years. EU applicants will only be eligible for the fees component of the studentship (no maintenance award is provided). For Non EU nationals the candidate must be "settled" in the UK.
Monday 18 February 2019
13 March to 21 March 2019
The largest of Ulster's campuses
When applying for this PhD opportunity please quote reference number: