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Applications of methanol and biodiesel in internal combustion engines have raised widespread concerns, but there is still huge scope for improvement in efficiency and emissions. The brand-new combustion mode, named as Intelligent Charge Compression Ignition (ICCI) combustion, was proposed with methanol-biodiesel dual fuel direct injection. In this paper, effects of injection parameters such as two-stage split-injections, injection timings, injection pressure and intake pressure on engine combustion and emissions were investigated at IMEP = 8, 10, and 12 bar. Results show that the indicated thermal efficiency up to 53.5% and the NOx emissions approaching to EURO VI standard can be obtained in ICCI combustion mode.

In this paper, an experimental study has been conducted to study the effects of iso-alkanes blending in diesel on combustion and emission characters based on a modified single cylinder diesel engine. Iso-octane, iso-dodecane and 2,2,4,4,6,8,8-heptamethylnonane (HMN) were chosen as test iso-alkanes. The direct injection timing was kept at 7 oCA BTDC. The injection pressure was maintained at 120 MPa. The study found that iso-alkanes had strong effects on the heat release phase under low load. The effects were weakened gradually with the increase of loads. The peak value of heat release curves and the maximum pressure rising rate gradually increased with the increase of loads. Blending iso-alkanes resulted in the increase of CO emissions and decrease of HC emissions. NOx emissions also decrease under low loads. Under high loads, blending iso-alkanes reduced the soot emissions significantly.

An experimental study was conducted on the combustion and emissions characteristics of duel fuel sequential combustion (DFSC) mode on a single-cylinder engine, applying port injection of n-heptane combined with in-cylinder direct injection of commercial gasoline, ethanol and n-butyl alcohol, respectively. Three-stage combustion, which consists of low- and high-temperature combustion of premixed n-heptane and high temperature combustion of directly injected gasoline-like fuels were observed. The effects of the premixed ratio and overall heating values per cycle on the combustion characteristics and emissions were investigated. The experimental results show that: with the increasing of premixed ratio and overall heating values per-cycle, the ignition timing of the directly injected fuels advances and the maximum pressure and maximum mass-averaged temperature increase.

Developing advanced combustion mode has been the active area for high efficiency and ultra-low emissions of the next-generation internal combustion engines. In this paper, a series of experiments were conducted in a modified single-cylinder compression ignition engine for operating a brand-new combustion mode denoted as intelligent charge compression ignition (ICCI) mode. By using two common-rail systems, commercial gasoline and diesel were alternately directly injected into the cylinder through multi-injection strategies in the injection timing range of 50~320 °CA BTDC. Thus, the in-cylinder stratified condition can be flexibly and accurately adjusted in this unique combustion mode. The key injection parameters, such as gasoline injection timing and diesel split ratio, were investigated to explore their effects on engine combustion, emissions, and fuel consumption.