Effect of regulated harmful matters from a heavy-duty diesel engine by H2/O2 addition to the combustion chamber

► The brake thermal efficiency is increased for 70 L/min of H2/O2 addition. ► The fuel consumption is reduced for 50-70 L/min of H2/O2 addition. ► The emissions of HC, CO, and CO2 were reduced due to improved combustion and the absence of carbon in hydrogen fuel. ► The emission of NOx was increased due to high temperature and oxygen present in the fuel mixture.