Performance Evaluation of Butanol-Water Diesel Emulsion in Turbocharged Diesel Engine at Variable Loads

Abstract

This study investigates the performance characteristics of a turbocharged diesel engine using water-diesel emulsion fuel blended with various proportions of butanol. The fuels tested include pure diesel (D), 5% water emulsion diesel (W5D), and three blends with added butanol: W5DBu5, W5DBu10, and W5DBu15. Experiments were conducted using an Isuzu 4JJ1 common-rail turbocharged diesel engine at engine loads of 20%, 35%, and 50%, with speeds ranging from 1,000 to 3,000 rpm. Results show that brake power and torque varied significantly with butanol addition. At 50% load, the maximum brake power was observed at 3,000 rpm for all fuels, where W5DBu15 achieved a peak of 33.2 kW compared to 31.8 kW for pure diesel. Similarly, brake torque was highest at mid-range speeds (1,500–2,000 rpm), with W5DBu15 reaching 210 Nm, slightly below diesel’s 218 Nm but notably higher than W5D at 193 Nm. Butanol addition improved brake thermal efficiency while reducing brake-specific fuel consumption, especially at moderate engine loads. The findings indicate that blending butanol with water-diesel emulsion enhances combustion efficiency due to higher oxygen content and specific heat of butanol. Thus, W5DBu10 and W5DBu15 demonstrate strong potential as alternative fuels, offering performance benefits without significant engine modifications.