Challenge: Improvement of kinetic models

Objectives:

• Extend experimental databases (elementary reaction rate and validation data) over unconventional conditions typical of innovative combustion processes.
• Extend the detailed chemistry and thermochemistry oxidation knowledge from fossil toward unconventional and bio-based energy carriers.
• Optimize chemical kinetic models for simulation of SECs combustion processes (high-pressure, high inlet temperature, massive dilution, multi- component fuels, etc.).

Detailed description of the WG1 activities can be found here (extract from the Action’s Memorandum of Understanding)

Summary of Work Group 1 Activities

The objective of Workgroup 1 has been successful pursued in the networking activities. Its fulfilment represents a fundamental and mandatory step for the fast deployment of Smart Energy Carriers (SECs). Indeed, the design and optimization of practical systems have to rely on feasible kinetic models. Experimental and numerical studies have been tackled as main complementary approaches, focusing on reference and up-to-date simple, lab-scale facilities as well as on advanced computational analysis. 

Detailed chemistry and thermochemistry for the combustion, pyrolysis, and oxidation of a wide palette of energy carriers of interest in concept of supporting the renewable energy have been the core of wg1 activities. Among the main outcomes of the research activities developed in the framework and with the support of SMARTCATs are:

– Natural gas mixtures: Further development of the existing detailed kinetic mechanisms for small (C₁-C₄) hydrocarbons has been made. Particular care has been devote to the operative conditions characteristics of advanced combustion technologies (such as MILD Combustion and Exhaust Gas Recirculation) and their effects on combustion kinetics, highlighting several critical issues.

– Simple molecules (large normal and iso-paraffins, alcohols, esters, saturated and unsaturated cyclic ethers (e.g. derivatives of furans)) present in new biofuel generation:

Detailed kinetic models for these fuels were developed and validated using acquired and available literature data. The oxygenated molecules, which were mostly studied, are bio-alcohol, dimethoxymethane, linear and cyclic ethers. The potential of bio-alcohol blends with traditional gasoline and its surrogates in terms of their impact on the ignition and knock propensity within spark ignition engines has been addressed.

– More complex molecules (as lignin, cellulose, ligno-cellulose, and derived molecules): 

A novel approach for the chemical representation of lignin for modelling the reaction kinetics of lignin in lignocellulosic biomass was made. For the first time, set of experimental data for the oxidation of two high molecular weight carboxylic acids was reported. To gain insight into the conversion of fuel-bound nitrogen, diethylamine was studied as a nitrogen-containing model compound present in biofuels.

– Complex mixtures of molecules (present in new biofuel generation, such as fatty acid methyl esters (FAME), hydrotreated vegetal oils (HVO), or biomass to liquid fuels (BTL) or in surrogates):

For a better modelling of FAME combustion, the oxidation of three reference (C₁₉) FAME was investigated in order to highlight the effect of double bonds on the reactivity and product distribution.

-Non-Carbon Fuels: In the last year of the Action, a great attention is risen on ammonia as  key energy carrier in the international community. Thus, a significant amount of experimental kinetic work has been undertaken, on pure ammonia and H2 and/or CH4 ammonia mixture under various combustion conditions. A very successful workshop has been organized on all aspects of Ammonia as SEC. Sulfur is also added to the palette of energy carriers.

The results of the activities of WG1 are reported in:

• Proceedings of the 1st General Meeting of SMARTCATs COST Action
• Proceedings of the 2nd General Meeting of SMARTCATs COST Action
• Proceedings of the 3rd General Meeting of SMARTCATs COST Action
• Proceedings of the 1st International Conference on Smart Energy Carriers
• FUEL Special Issue (2018)
• Energy&Fuel Special Issue
• FUEL Special Issue (2019)

and in the material of Topical and co-organized workshops in the framework of Work Groups 1/2/5:

• Ammonia for Fuelling Future Energy
• Gas-phase Reaction Kinetics of Biofuels Oxygenated Molecules

 ➡ Proceedings, presentations, media,  Special issues are part of the Final Action Report