FUTURE COMBUSTION TECHNOLOGY FOR SYNTHETIC AND
RENEWABLE FUELS IN COMPRESSION IGNITION ENGINES
REFUEL
MARTTI LARMI, TEEMU SARJOVAARA AND AKI TILLI
TKK Helsinki University of Technology
Internal Combustion Engine Research Group
PO BOX 4300, FIN-02015 TKK
Phone +358-9-451 3460, E-mail teemu.sarjovaara@tkk.fi
MATTI KYTÖ AND PÄIVI AAKKO-SAKSA
VTT Technical Research Centre of Finland
ANDERS BRINK AND MIKKO HUPA
ÅAU Åbo Akademi University
ANNELE VIRTANEN
TUT Tampere University of Technology
INTRODUCTION
“Future Combustion Technology for Synthetic and Renewable Fuels in Compression
Ignition Engines, Project ReFuel” is a research project towards emission-free engine
combustion with future fuels and future combustion technology. The project will be carried
out in the years 2009 – 2011.
The compression ignition (CI) and spark ignition (SI) engines have been developed for
more than a century. The development work has focused on optimizing the processes for
crude oil based gasoline and diesel fuels. During the last years the awareness of the effect
of the CO2 emissions to the global warming and the limited resources of crude oil in the
near future have put the bioderived renewable fuels in significant interest, especially in
compression ignition engines due to high efficiency compared to spark ignition engines.
The novel renewable fuels have excellent physical and chemical properties. For example
paraffinic high cetane number (CN) fuels do not contain aromatic compounds and they are
totally sulphur free. Fischer-Tropsch (FT) diesel fuel and Neste Oil’s NExBTL are
examples of paraffinic high cetane number diesel fuels.
These fuels do not suffer from storage and low temperature problems, as did the fatty acid
methyl esters (FAMEs). The combustion related properties of the novel fuels are in most
cases better than with crude oil based fuels. Especially very high cetane number, absence of
polyaromatic hydrocarbons (PAH) and high oxygen content in some cases allow far more
advanced combustion strategies than what has been possible with current fossil fuels. Due
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to these advantageous properties, new combustion technologies allow us to reduce
significantly nitrogen oxide (NOx) emission without suffering from traditional trade-off
with increased particle matter (PM) emission.
PROJECT OBJECTIVES
The objective of this project is to develop new extremely low emission combustion
technologies for renewable fuels in compression ignition engines. The target is to cut down
emissions at least by 70%. The scope is to utilize the physical and chemical properties of
the renewable fuels that differ from properties of the traditional crude oil based fuels and to
develop optimum combustion technologies for them.
Together with low CO2 footprint and by utilizing the advantageous combustion related
properties of the novel renewable fuels, new future combustion technologies will be
developed that enable extremely low emission engine combustion in future.
METHODS AND IMPLEMENTATION
This study will focus firstly, on paraffinic high cetane number fuels and secondly, on fuels
with high content of oxygenates.
The project will consist of
• Literature review and reaction scheme evaluations
• Fuel spray studies
• Emission mapping calculations
• Optimum combustion design with CFD
• Engine tests with a high-speed research engine, LEO
• Engine tests with a medium-speed research engine, EVE
• Extensive emission measurements
• Particulate emission analysis
• Project reporting and analysis
PROJECT ORGANISATION AND NETWORKING
The project partners in Finland are
• Helsinki University of Technology (TKK),
• Tampere University of Technology (TUT),
• Technical Research Centre of Finland (VTT) and
• Åbo Akademi University (ÅAU)
TKK Internal Combustion Engine Research Group in the Department of Energy
Technology is coordinating the project, running the research engines, carrying out engine
experiments, making the combustion optimizations and carrying out fuel spray studies.
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VTT Engine Research Group is the main expert of alternative fuels and their properties.
VTT will also carry out extensive emission tests including particulates mass measurements
and non-regulated emissions.
ÅAU Laboratory of Inorganic Chemistry will take the responsibility of combustion
chemistry and emission chemistry. ÅAU will study combustion and emission reaction
schemes and simulate combustion and emission kinetics for emission mapping and
combustion optimization.
TUT Research Group of Aerosol Physics will carry out particulate mass analysis of the
selected combustion and fuel configurations. TUT will analyze particulate size distributions
and particle consistences.
INTERNATIONAL NETWORKING
The project will be part of a Collaborative Task “ReFuel” of the International Energy
Agency (IEA) Combustion Agreement coordinated by Finland. Countries Participating the
Combustion Agreement are: Belgium, Canada, Germany, Finland, Italy, Japan, Korea,
Norway, Sweden, Switzerland and USA. Moreover, the international program “ReFuel”
will be a collaboration framework between IEA Combustion Agreement and IEA AMF
(Advance Motor Fuels) Agreement.
Parallel projects are started in 2009 in Sweden and in Norway. Additional projects will join
the Collaborative Task later on.
Keywords:
Engine, combustion, synthetic, renewable, fuel, compression ignition, emission reduction