Comparative study of standard engine and modified engine with different piston bowl geometries operated with B20 fuel blend

摘要

The diesel engine parameters are more compatible with diesel fuel operation. However optimization of engine parameters for dairy scum biodiesel operation in diesel engine is highly pronounced as dairy scum biodiesel has higher viscosity and lesser heating value when compared to petroleum diesel. In the present study, nozzle hole (NH) geometry and engine parameters namely injector opening pressure (IOP), injection timing (IT), compression ratio (CR) are modified to appraise (optimize) the diesel engine performance. At the end optimized engine parameters (LOP: 230 bar, IT: 26 deg.bTDC, CR: 18, NH: 5 holes) are carried further to investigate the effect of piston bowl geometry on diesel engine performance operated with B20 (20% biodiesel+ 80% diesel) fuel blend. The experimental study revealed that the modified engine with Re-entrant Toroidal Piston Bowl Geometry (RTPBG) showed improved performance, combustion and emission characteristics when compared with standard engine (B20-SE) and modified engine (ME) with different piston bowl geometries, namely Hemispherical Piston Bowl Geometry (HPBG), Straight Sided Piston Bowl Geometry (SSPBG) and Toroidal Piston Bowl Geometry (TPBG). This improvement could be attributed to improved fuel atomization, smaller size droplets, increased cylinder temperature, swirl and squish, turbulent kinetic energy of the charge during combustion. (C) 2018 Elsevier Ltd. All rights reserved.