Experimental Studies Of Diesel Fuel And Gasoline Fuel Surrogates On Low-temperature Combustion Of Engines

Low Temperature Combustion (LTC) is considered as a new combustion process. Both combustion fueled with diesel in LTC conditions and Gasoline Direct-Injection Compression Ignition are hot research topics in the world which show the potential to meet stringent emission legislation. In this paper, experimental studies of diesel fuel and gasoline fuel surrogates in LTC conditions were carried out in the diesel engine. The experiment data will provide reliable databases for the development of the chemical kinetic model and associated investigations into kintinetics in the future.Firstly, the investigations on surrogates for diesel fuel were carried out in the diesel engine. The results show that n-heptane didn’t match well with diesel on combustion and emission characteristics. Toluene had strong effect on ignition delay especially in LTC conditions. It can also be found that the ignition delays of TRF20 were very close to those of diesel in the whole oxygen concentration conditions. However, the smoke emissions between diesel fuel and TRF20 still had some disparities especially at low intake oxygen concentrations. Compared to TRF20, TRF20/5%1-hexene mixture’s production of C2H2 was higher at lower intake oxygen concentration. Therefore, the smoke emission of TRF20/5%1-hexene mixture was higher than that of TRF20 and was closer to that of diesel. Besides, TRF20/5%1-hexene mixture had a better match in ignition delay, CA50 and other emissions in the whole oxygen concentration conditions.Then, surrogates for gasoline fuel have been studied at medium load and low load. As the results shown, the ignition delay and emissions of the PRF can’t match well with those of gasoline fuel. At the medium load, TRF25 are similar with gasoline on combustion and emissions characteristics, but inappropriate at the low load. So besides RON, MON and Sensitivity, the author considered the impact of the component. It can be found that the ignition delay and CA50 of TRF/diisobutylene mixtures can match very well with gasoline at both medium load and low load. Compared to TRF25, the NOx, HC and CO emissions of TRF/diisobutylene mixtures are more similar to gasoline.