Evaluation of comparative combustion, performance, and emission of soybean-based alternative biodiesel fuel blends in a CI engine

Abstract In this study, engine tests lead the studies on using diesel fuel (ultra-low sulfur diesel fuel, ULSD), soy-based biodiesel and diesel blends. Performance, combustion and exhaust emission values obtained as ULSD and biofuel blends are presented under load of 3.6 kW, 7.2 kW and 10.8 kW and constant engine speed of 1500 rpm in a diesel engine power generator and compared with ULSD. The maximum increment in break specific fuel consumption (BSFC) is observed at 3.6 kW with SOB20 fuel as about 8% compared to ULSD. Although the BSFC of soy-based biodiesel is high on low loads compared to the ULSD, both types of fuel gave almost identical results. The maximum increment of BTE compared to diesel fuel is occurred as 3.1% when the engine fueled with SOB20 fuel at 10.8 kW. All biodiesel blends are almost the same efficiency as diesel however, when the load increased from 3.6 kW to 10.8 kW, the HC values of ULSD, SOB5 and SOB20 are increased by 28%, 26% and 6%, respectively. However, experimental results show that using biodiesel blends partly similar to ULSD operation in diesel engine according to cylinder gas pressure, heat release rate, heat release rate, knock density and AGT.