Development of the full Lagrangian approach for the analysis of vortex ring-like structures in disperse media: application to gasoline engines

As vortex ring-like structures in two-phase mixtures occur in a wide range of systems such as gasoline engines, appropriate mathematical models of such processes would allow engineers to rapidly test novel ways of optimising and improving a range of engineering systems before resorting to costly experimental evaluation of new technologies. This proposal is therefore concerned with the generalisation of a mathematical approach known as the full Lagrangian approach (also known as the Osiptsov-Lagrangian method) to enable it to model vortex ring-like structures in two-phase mixtures. The main focus of the project will be on the development of this approach to enable its use in the modelling of three-dimensional processes within a Computational Fluid Dynamics (CFD) framework. The project will also investigate the possibility of constructing new mathematical models of vortex ring-like structures, to take into account additional complications relevant to certain engineering applications such as the effect of an elliptical core.

This new approach to the modelling of multiphase flows will incorporate the jet and droplet break-up models developed through a currently active EPSRC project EP/F069855/1. Where appropriate, predictions resulting from the new models will be compared with predictions based on three dimensional numerical simulations of transient vortex ring-like structures, based on the conventional research CFD code KIVA 3 and commercial CFD code FLUENT.

A feasibility study will also be performed into the modelling of these vortex ring-like structures based on the combination of the full Lagrangian approach for the dispersed phase and the vortex method for the carrier phase to examine the advantages and limitations of the different mathematical approaches.

Finally, predictions from numerical and analytical models will be validated against in-house experimental results obtained in gasoline engine-like conditions allowing an assessment to be made into the applicability of using the models for the characterisation of processes in gasoline engines.

This will be a collaborative project involving external consultants Professor A. Osiptsov (Lomonosov Moscow State University, Russia) and Dr. F. Kaplanski (Tallinn Technical University, Estonia), whose expertise is mainly focused on the development of the full Lagrangian method for multiphase flows and semi-analytical vortex ring models. It will be led by Professor S. Sazhin, whose expertise includes the development of new physical models of fuel droplet and spray processes as applied to modelling internal-combustion engines. The co-investigators Dr. S. Begg and Professor M. Heikal will advise on the relevance of the models to automotive applications and provide the experimental data required for the validation of the models. A Research Fellow will be included in the project. This project will ensure a qualitatively new level of physical and mathematical models, developed in the previously funded EPSRC project EP/E047912/1, supporting the collaboration between the PI, co-investigators and Dr F. Kaplanski, and the currently active project EP/F069855/1.

It is expected that outside of the academic research community the principal beneficiaries of this research will be mainly the automotive industry via the industrial partner, Ricardo Consulting Engineers Ltd. The modellers of the processes in internal combustion engines will be able to use more accurate models for droplet heating and evaporation, which will lead to more reliable predictions of the models. The project's results will be reported at the 10th and 11th Euromech Fluid Mechanics Conferences, which alongside academics attract many representatives from industry, including the automotive industry.
The project is expected to directly benefit the designers of fuel injection systems through an increased understanding of droplet dynamics. Importantly, further understanding of the compromise between the requirements of a direct fuel injection system, that can optimally satisfy both homogeneous and stratified charge operation, whilst simultaneously minimising engine emissions, will be incrementally advanced. It is expected that some of the results will be directly applicable to the modelling of other spray phenomena (e.g. aerosol sprays in medicine or agriculture).
The results will be disseminated to a wider audience through publication on the Sir Harry Ricardo Laboratories (SHRL) website and the University of Brighton open access repository. This will allow the general public to familiarise themselves with the state of the art developments in this field. A specific website for the project will be set up.
Two Visiting Researchers, Professor Alexander Osiptsov and Dr Felix Kaplanskii, are expected to have direct contact with Ricardo Consulting Engineers Ltd and the wider engineering and environmental community via their work at the Sir Harry Ricardo Laboratories. It is likely that their involvement in the project will contribute to the creation of links between the British, Estonian and Russian academic and industrial communities. A collaboration agreement between the Sir Harry Ricardo Laboratories and the Visiting Researchers' home institutions, Moscow State University (Russia) and Tallinn Technical University (Estonia) will be prepared in due course if the project is funded by the EPSRC.
It is expected that the Research Fellow working on this project will be primarily involved in all impact activities, with strong support from the Principal Investigator, Co-investigators and Visiting Researchers.