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A novel combustion system called Jet Controlled Compression Ignition (JCCI) is investigated to directly control the combustion phasing of premixed diesel compression ignition. Experiments were conducted on a single-cylinder naturally aspirated diesel engine at 3000r/min without EGR. The experimental results showed a good linear relationship between spark timing in the ignition chamber and CA10 and CA50, which indicated the ability for direct combustion phasing control in premixed diesel combustion. The NOx and soot emissions gradually changed with the spark advance angle. Then, load sweep experiments were performed with fixed spark timing. The results showed the onset of combustion was almost unchanged over a wide load range. Additionally, NOx emission was greatly reduced at all test loads compared with the original engine. Soot emission was reduced at a comparatively high load while similar with that of the original engine at low loads.

To directly control the premixed combustion phasing, a novel method called Jet Controlled Compression Ignition (JCCI) is investigated. Experiments were conducted on a single cylinder natural aspirated diesel engine at 3000 r/min without EGR. Numerical model was validated by pressure and heat release rate curves at a fixed spark timing. The simulation results showed that the reacting active radical species with high temperature issued from ignition chamber played an important role on the onset of combustion in JCCI system. The combustion of diesel pre-mixtures was initiated rapidly by the combustion products issued from ignition chamber. Consequently, the experiments of spark timing sweep were conducted to verify the above deduction. The results showed a good linear relationship between spark timing and CA10 and CA50, which validated the ability for direct combustion phasing control in diesel premixed combustion.