Performance and engine exhaust study of a CI engine in dual fuel mode using diethyl ether as cetane enhancer additive

In this experiment, emission and performance analysis were conducted on a compression ignition (CI) engine operating with a blend of Karanja methyl ester and diesel as the pilot fuel. Diethyl ether (DEE) was used as a cetane enhancer to improve the brake thermal efficiency (BTE) of dual fuel (DF) engines. Producer gas (PG) was utilized to maximize diesel savings. The results show that BTE decreased in DF runs while using PG. However, when a 5% volume fraction of DEE was mixed with the selected pilot fuels, it led to an improvement in BTE during the DF run. The emission curves also reveal the positive impact of DEE on DF engine performance. Further investigation showed that a 10% volume fraction of Karanja methyl ester (B10) blended with diesel, when additionally mixed with 5% volume of DEE (referred to as 5DEE), achieved a BTE of 26% during DF mode operation with PG. In comparison, B10+PG, Diesel+PG, and Diesel+5DEE+PG reached BTEs of 23.75%, 24.2%, and 27.2%, respectively. Among these combinations, B10+5DEE+PG showed the highest reduction in smoke opacity (51.3%) and nitric oxide (54%) emissions during DF operation compared to the base results. Additionally, B10+5DEE+PG exhibited the lowest increase in hydrocarbon emissions (35.4%) compared to other DF operation combinations.