Challenge: Knowledge transfer towards technology applicatione
- Integrate detailed kinetic mechanisms in large scale numerical simulations.
- Develop reliable, widely applicable and affordable turbulence/chemistry interaction models.
- Develop methodologies to constructively couple simulations and experiments, to provide estimates of the uncertainty related to numerical predictions.
Detailed description of the WG5 activities can be found here (extract from the Action’s Memorandum of Understanding)
Advancement of the activities
In the last two years, significant progress has been made in the simulation of various combustion systems, from lab-scale to industrial ones. The research efforts have been particularly focused on the development and optimisation of turbulence-chemistry interactions descriptions in non-conventional combustion systems (i.e. MILD and diluted combustion, oxy-conditions, …). In such regimes, the separation of turbulent and chemical scales vanishes, and flamelet-based approaches are inappropriate. Finite-rate based approaches based on Perfectly Stirred Reactor and Partially Stirred Reactor closures have been successfully applied to lab-scale and semi-industrial configurations, in the context of both RANS and LES closures for turbulence description.
Flamelet-generated manifold (FGM) approaches, with appropriate choices of progress variables, have been also proposed with promising results.
In parallel, significant efforts have been dedicated to the development of reliable and robust reduction procedures of detailed chemical mechanisms, to allow their use in CFD simulations, without significantly compromising the accuracy of the predictions. New and conventional reduction methods were evaluated (PCA & Kriging, DRG-related techniques, CSP …), for the a priori and on-the-fly development of kinetic schemes valid in a wide range of conditions, relevant for turbines, furnaces, engines and co-combustion systems.
At the same time, attention has been devoted to the development of methods for the quantification of uncertainties affecting the prediction of detailed kinetic schemes.
In addition, a detailed evaluation on the error sources for several techniques, employed in combustion systems, including electron-ionization (EI), photoionization (PI) molecular-beam mass spectrometry (MBMS) has been made.