Cylinder Selective Combustion, the New Diesel Dual Fuel Combustion Control Concept for Low Load Operating Condition 2018-01-1733
ABSTRACTDiesel dual fuel (DDF) operated under moderate load condition emits a lot of THC and CO emissions. Even these emissions have been improved significantly by Dual Fuel Premixed Charge Compression Ignition “DF-PCCI”  combustion control technique which was proposed by the author. However, for very low load, DF-PCCI technique still cannot be implemented because of misfire. To get rid of this situation, the new combustion control concept so called Cylinder Selective Combustion (CSC) has been proposed. From the fact that, at low load condition, diesel combustion has THC and CO emissions lower than DDF combustion and DDF emissions can be improved significantly by DF-PCCI concept for higher load. So, in the new concept, some cylinder was selected to run with very low IMEP diesel combustion and some cylinder was selected to run with higher IMEP DF-PCCI combustion. The IMEP ratios between DF-PCCI and diesel have been optimized for each engine speed and engine load. The engine and vehicle test results show that more natural gas can be utilized with smooth engine running without any misfire meanwhile the THC and CO emissions can be reduced significantly.