Ion current sensing in an optical HCCI engine with negative valve overlap
Journal article, 2007

Ion current sensors have high potential utility for obtaining feedback signals directly from the combustion chamber in internal combustion engines. This paper describes experiments performed in a single-cylinder optical engine operated in HCCI mode with negative valve overlap to explore this potential. A high-speed CCD camera was used to visualize the combustion progress in the cylinder, and the photographs obtained were compared with the ion current signals. The optical data indicate that the ions responsible for the chemiluminescence from the HCCI combustion have to be in contact with the sensing electrode for an ion current to start flowing through the measurement circuit. This also means that there will be an offset between the time at which 50% of the fuel mass has burned and 50% of the ion current peak value is reached, which is readily explained by the results presented in the paper. In addition the results show that the ion current sensor generates good combustion phasing signals for HCCI combustion with negative valve overlap at low engine speeds and low engine loads, provided that the electrode area and bias voltage are both sufficiently large.


Martin Larsson

Chalmers, Shipping and Marine Technology, Division of Marine Design

Ingemar Denbratt

Chalmers, Applied Mechanics, Combustion and Propulsion Systems

Lucien Koopmans

Volvo Cars

SAE Technical Papers

01487191 (eISSN)


Subject Categories

Mechanical Engineering



More information

Latest update

2/1/2022 1