Due to its oxygen (O) content, biodiesel (BD) is advantageous in that it lowers PM emissions in CI engines. Therefore, BD is considered one of the best candidates for low temperature combustion (LTC) operation because its use can extend the regime for simultaneous reduction of PM and NOx. Thus, in this study, LTC operation was realized using BD and diesel with a 5 similar to 7% O-2 fraction. Engine test results show that the use of BD increased the efficiency and reduced emissions such as PM, THC, and CO; furthermore, IMEP reduced by 10 similar to 2% owing to the lower LHV of the fuel. In particular, smoke was suppressed by up to 90% because O atoms in the BD enhanced the soot oxidation reaction. To compensate the IMEP loss, turbocharging (TC) was then tested, and the results showed that the power output increased and PM was reduced further. Moreover, TC in BD engine operation allowed a similar level of reduction in both NOx and PM at 11 similar to 12% O-2 fraction, suggesting that there is a potential to widen the operating range by the combination of TC and BD.
