Host Institution: Université Libre de Bruxelles (Belgium)
Aero-Thermo-Mechanical Department, Université Libre de Bruxelles
The main research area which I am focused on is related to the numerical simulation of combustion process, and specifically aimed at Sub-grid models for LES simulation of non-conventional combustion regimes. The research activities I am going to conduct regarding my thesis topic are at first, making a combustion-LES tool implementing the implicit LES, EDC and PaSR paradigms available using the OpenFOAM code. Second, the impact of detailed and reduced chemistry will be also assessed. And in the end, a validation process by using data from literature or experiments will be included. My research goal is to have an insight investigations on the role of filtering and sub-closure models for relatively low-Da number systems.
Project title: Sub-grid models for LES simulation of non-conventional combustion regimes
Objectives. Combustion models for LES usually rely on the flamelet assumption and related modifications, which constrain the thermochemical space accessible in the numerical simulation. Whilst the use of transported PDF methods in LES appears still computationally prohibitive, especially for practical combustion systems, there are a number of sub-grid models showing promise for the inclusion of detailed kinetic mechanisms. The objective of the present study will be that of assessing the role of sub-grid models for the LES simulation of non-conventional combustion regimes. In particular, implicit LES (ILES) will be compared to other existing closures for finite-rate chemistry models, including Eddy Dissipation Concept (EDC) and the Partially Stirred Reactor approach (PASR).
Expected results. The doctorate is expected to provide insight in the role of filtering and sub-closure models for relatively low-Da number systems as the ones investigated in the present project. A combustion-LES tool implementing the implicit LES, EDC and PaSR paradigms shall be made available using the OpenFOAM code. This will allow including detailed chemistry in LES simulations. Moreover, the impact of detailed and reduced chemistry will be also assessed, allowing optimising computational resources in the framework of large-scale combustion simulations. The numerical simulations will be validated using data from the literature and collected in a newly designed MILD combustion furnace installed at ULB.
Planned secondment. DE-TUD (8-10 months). Validation of the EDC and PaSR approaches.