|A HAJI jet.|
Ford Motor Company of Australia has confirmed its support of a long-term research project by the University of Melbourne to study efficient hydrogen fueled vehicle technologies. The project also received a A$1.2 million grant from the Victorian State Government.
The first stage of the project aims to develop, build and test a hydrogen-fueled turbocharged Ford 6-cylinder engine using advanced hydrogen engine technology (HAJI: Hydrogen-Assisted Jet Ignition) developed by the Transport Group at the University of Melbourne.
HAJI is a physio-chemical combustion enhancement system developed to support the combustion of a variety of liquid and gaseous fuels. The HAJI device replaces the spark plug in otherwise standard four stroke, spark ignition, internal combustion engines and can ignite ultra-lean air/fuel mixtures which are far beyond the stable ignition limit of a spark plug. Ultra-lean combustion produces higher thermal efficiencies, reduced combustion temperatures, heat transfer losses and a near elimination of NOx emissions.
Ignition stability is achieved by relocating the spark plug electrodes to a small prechamber which is connected to the combustion chamber via a shaped orifice. A minute quantity of hydrogen is injected into the prechamber prior to ignition, thus increasing flame kernel growth dramatically. The hydrogen rich combustion within the prechamber causes a highly turbulent jet containing chemically active species to eject from the orifice and spread into the main chamber. This physically and chemically active jet enhances the combustion of the mixture in the main chamber, providing extra-ordinary tolerance of main chamber conditions.
Due to its stable nature, HAJI allows engines to operate efficiently even on poorer quality renewable fuels. The Transport Group is also studying the cause of hydrocarbon emissions under ultra lean conditions, and working on a direct injection prototype to reduce emissions even further.
Experimental results have shown that at all load points, a HAJI-fitted research engine in gasoline mode has increased thermal efficiency by up to 41%, reduced CO by 90% and increased HC emissions by up to 3.5 times while maintaining an almost zero NOx capability (<0.1 g/kWh) over its spark ignition gasoline counterpart. The same tests when performed with a hydrogen fuel supply showed increased thermal efficiency of up to 10% over its spark ignition hydrogen counterpart and reduced CO, HC and NOx emissions to near zero levels.
Ford Australia will contribute engines and resources to the project which, along with the State Government grant, will assist with engine and vehicle development. The project will also investigate hydrogen generation and storage technology.
The long-term research project is scheduled to begin in July.
In late 2006, Ford Australia joined the University of Melbourne and the Victorian State Government to form the Advanced Centre for Automotive Research Technology (ACART), the purpose of which is to enhance vehicle development in Australia. ACART will eventually include a new engine dynamometer facility, a diesel test cell, and a world-class environmental wind tunnel available for use by the wider automotive development community.
Publications list on HAJI (University of Melbourne)