The breadth and coverage of analytical expertise in the IEA Technology Collaboration Programmes (TCPs) are unique assets that underpin IEA efforts to support innovation for energy security, economic growth and environmental protection. The 39 TCPs operating today involve about 6 000 experts from government, industry and research organisations in more than 50 countries1.

Clean and Efficient Combustion (Combustion TCP)


Simulating combustion to reduce CO2

The Combustion TCP carries out experimental and computational research projects related to internal combustion in engines and gas turbines, and furnace combustion. A new, more accurate model of the chemical reaction in combustion engines enables accelerated analysis of efficiencies and CO2 emissions reductions. 

Comparison of modelling approaches simulating the chemical reactions in the combustion process.*

Reducing fossil fuel consumption and CO2 emissions in the transport sector are challenging priorities for policy makers. While increased consumption of low-carbon fuels and deployment of hybrid or electric vehicles present viable alternatives, the majority of vehicles operating today still use conventional fuels associated with the internal combustion (IC) engine. Further understanding of the physics and chemistry of the combustion process is fundamental to achieving improvements in fuel efficiency, reducing greenhouse gas emissions and pollutants, and transitioning to alternative fuels. 

For these reasons, the Combustion TCP set out to study the chemistry of the combustion process in order to model development and analysis of clean and efficient engine combustion. The main focus of this collaborative study is to extend and to improve the understanding of kinetics and fluid dynamics through computation in order to reduce formation of pollutants and to enable reductions in GHG.

In order to develop more accurate fuel chemistry models to improve engine designs, analytical tools capable of simulating chemical reactions in engines were elaborated. Based on the “fast solver” principle, which provides information on the degrees and rates of reactants conversion, the formation of pollutants, and the effects of additives, participants designed an improved fast solver approach.

This was undertaken in co-operation with automobile and equipment manufacturers, national research laboratories, universities and industry associations. The improved version includes preconditioning the model with specific parameters (e.g. flame speed, one- dimensional diffusion, piston and other models), creating a mechanism to debug tools, and leveraging the analysis which accelerates the calculations of the combustion effects. Participants derived an improved simulation performance and efficiency through more accurate calculations, a new computing architecture and improved physical models.

The debugging and diagnostics have enabled fuel researchers to create more robust and accurate models. In addition, the updated fast solvers have accelerated results from days (and in some cases weeks) to less than an hour. The new fast solvers and fuel model are able to deliver more predictive engine simulations that will facilitate the design and development of highly efficient, cleaner combustion engines worldwide. The new solvers have been licensed to Convergent Sciences Inc. (CSI) for use in their calculations, widely used by engine manufacturers.

These and other findings are available in the final presentation, Improved Solvers for Advanced Engine Combustion Simulation.

* Graph adapted from data provided by the Combustion TCP


  • Combustion of alternative fuels
  • Combustion chemistry
  • Gas engines
  • Hydrogen gas turbines
  • Low-temperature combustion
  • Nanoparticle diagnostics
  • Single contributor tasks
  • Sprays in combustion


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Contracting Parties  11  -  -
Sponsors -  -

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