Engine Performance and Emission Studies with Cotton Seed—Simarouba and Cotton Seed—Mahua Oil Blends as a Partial Replacement Biofuel

In the present paper, the performance of a single cylinder CI engine using dual blend of cotton seed—Simarouba oil (CSSB) and cotton seed—Mahua oil (CSMB) biodiesel was investigated. To accomplish this, CSSB and CSMB blends are used in equal proportions in diesel to prepare three different blend ratios B10 to B30 with an increment of 10%. Test run was done to evaluate different performance parameters at normal and advanced injection timing keeping compression ratio constant. Performance study revealed that the highest brake thermal efficiencies recorded by the respective blends CSSB30 and CSMB30 were 28.4% and 29.8% as against 29.1% of neat diesel with 4–8% more fuel consumption per kW of power generated, compared to neat diesel. Also considerable drop in emission was found in CO, UBHC at full load conditions, compared to diesel, respectively, between 25% less CO (at half load and with CSSB20) and 2.85% less UBHC (at half load and with CSSB10) to 71.42% less CO (at full load and with CSMB30) 57.69% less UBHC (at full load and with CSMB30), respectively. Advancing the injection, HC emission increased from 3.5% at ¾ load to 35.48% at full load (CSSB20 blend) compared to diesel. Further, it could be noted that CO emission with advanced injection was still lower (even though it increased by 50% compared to normal injection with CSSB20A) except at full load where diesel emitted 31.94% (compared to CSSB20) and 92.69% (compared to CSMB20) less. To conclude, the lower biodiesel blends of CSSB and CSMB could be used as partial replacement to diesel, with comparable engine performance coupled with lower UBHC and NO_x emissions.