Potential of Concomitant Injection of CNG and Gasoline on a 1.6L Gasoline Direct Injection Turbocharged Engine 2011-01-1995
The use of CNG in modern spark ignition turbocharged engine
offers many advantages such as high knocking resistance, low CO₂
emissions and high specific power outputs. On the other hand,
compared to gasoline, the volumetric efficiency is significantly
decreased when CNG is port-injected due to its low energy density.
In order to address this issue, recent studies have successfully
highlighted the advantages on port-injection engines of the
CIGAL™ concept (Concomitant Injection of Gas And Liquid fuels)
from IFP Energies Nouvelles.
However, the combination of port-injection of CNG with direct
injection of gasoline remains unexplored. This paper investigates
this novel injection concept on the four-cylinder 1.6L turbocharged
GDI engine with inlet variable valve timing resulting from the
cooperation between PSA Peugeot-Citroen and the BMW Group. This
engine was fitted with an independent CNG port-injection system and
a specific engine management system was implemented in order to
allow concomitant injection operation.
The first part of the study investigates the potential of
concomitant injection compared to gasoline and methane operation.
On the stock configuration, 29 bar BMEP (370 N.m) were reached at
2500 rpm with 30% gasoline and 70% methane in stoichiometric
conditions. Also, significant reductions of fuel consumption and HC
emissions were observed. Full load tests carried out with a smaller
turbocharger enhanced the synergy effect between the two fuels at
The second part of this work focuses on the reliability of the
gasoline direct injectors during CNG operation. Temperature
measurements on the gasoline injector nozzles were carried out in
gasoline, CNG and concomitant injection modes. Finally, the results
of gasoline direct injectors durability tests under CNG and
gasoline operation are discussed.
Citation: Obiols, J., Soleri, D., Dioc, N., and Moreau, M., "Potential of Concomitant Injection of CNG and Gasoline on a 1.6L Gasoline Direct Injection Turbocharged Engine," SAE Technical Paper 2011-01-1995, 2011, https://doi.org/10.4271/2011-01-1995. Download Citation
Jerome Obiols, Dominique Soleri, Nathalie Dioc, Marc Moreau