Effect of acetylene addition on performance, emission and combustion characteristics of neem biodiesel and corn biodiesel-fueled CI engine

The present experimental study aims to explore the effect of acetylene addition along with intake air with neem biodiesel (NOME)-/corn biodiesel (COME)-fueled single-cylinder CI engine in dual-fuel mode. Both types of biodiesel exhibited inferior combustion owing to poor physical properties in comparison with diesel. Acetylene was inducted in the intake manifold along with intake air at different mass shares with both neem biodiesel and corn biodiesel. Tests were also conducted with acetylene induction with diesel and taken as base data for comparison purpose. Tests were conducted at 50% and 100% load conditions at various acetylene mass shares until the knock limit. It was observed that acetylene addition increased brake thermal efficiency (BTE) with all the test fuels at 100% load and proportional to increase in mass flow rate of acetylene. BTE was improved by about 6-13% at knock-limited acetylene share for all the test fuels at 100% load, while the improvement was not much significant at 50% load. In comparison with diesel, biodiesel emitted higher NOx due to oxygen presence and the emission further increased with the addition of acetylene at both the load conditions. On the contrary, smoke emissions were reduced significantly with acetylene addition with the test fuels at both the load conditions. HC, CO and CO2 emissions were reduced with acetylene induction, and reduction was maximum at knock limit. It can be concluded that the poor performance and combustion associated with biodiesel can be improved with acetylene induction. The combination of biodiesel with acetylene is novelty of this present work.