Numerical modelling of the premixed compression ignition engine for superior combustion and emission characteristics

Abstract

The detailed investigation of biodiesel premixing is done in this research in order to make an attempt to reduce greenhouse gas emission, particularly NOx. From the literature survey, it is found that the effect of premixing is not concentrated enough and significant effect of it is yet to be analyzed. The impact of the biofuel premixing on the performance, combustion and emission characteristics was analyzed numerically. Numerical modelling was applied to do such analysis. The simulation for the combustion process in the combustion chamber was done to validate the comparison of a number of cases of different fuel. During the simulation process different fuel conditions were considered. A set of tests was carried out to find the premixing quality. Initially, pure diesel as fuel and the mixture of plain diesel and biodiesel were used to perform the tests. Secondly, biodiesel as fuel and its blends were used but the premixing was done. Similarly, another combination of pure diesel and plain premixed biodiesel in the combustion chamber was also analyzed. The different proportions of the fuel conditions are D (pure diesel), B10, B20 and B100 with B20%, B40% and B60% premixing biodiesel. The premixing effect was also identified by using both without premixing and with premixing fuel conditions in the combustion chamber. The reduced smoke emission was achieved by using the premixed fuels in the chamber in the second case. However, the emission of NOx was increased. Similarly, in the case of plain diesel as fuel and plain biodiesel as premixed fuel, the amount of smoke was reduced significantly but there was no high increment in the emission of NOx. Premixing biodiesel with the combination of pure diesel as the primary fuel provided the improved torque and power output whereas the reduced BSFC.