Spray analysis of Palm-Based biodiesel to correlate performance and combustion analysis of a compression ignition engine.

• Observation of spray of biodiesel is done to correlate with engine performance. • Mass of fuel molecules of B100 are found to be heavier than B0 and B50. • Mass of fuel molecules of B50 and B0 are found to be similar. • Satuer mean diameters of fuel molecules of B50 and B100 are larger than diesel. • Penetration lengths of vapour of B50 and B100 are 6.28% and 13.75% longer. • Combustion duration B0, B50 and B100 are 52°CA, 57°CA and 59°CA, respectively. Palm oil diesel (POD) is derived from palm oil using an esterification process. POD has similar physicochemical properties to fossil diesel, and this allows POD to be the primary substitute to diesel. However, existing research has found that the combustion of POD in CI engines produce lower performance standards than pure diesel. This is due to POD having a higher viscosity, density and presence of heavier molecules resulting in poor evaporation and mixing with the air leading to higher brake specific fuel consumption (BSFC) and reduced power. This research aims to observe the fuel spray behaviors inside the combustion chamber and corelate these with the lower performance of POD than diesel. POD is tested at 100% (B100) and, blended with diesel at a ratio of 50/50 (B50) by volume to reduce the viscosity. The study of spray properties in real engines is expensive and difficult, with most studies being performed in constant volume transparent chambers using Mie-scattering and Schlieren imaging techniques. Therefore, the engine simulation is conducted using ANSYS Forte software to observe the in-cylinder spray behaviors. A 26-kW diesel engine used in a generator is modelled using SolidWorks with respective performance parameters noted from simulation data. The CHEMKIN-PRO software is used to create POD by solving thousands of reaction combinations. Spray analysis of fuels shows longer penetration lengths with POD, higher Sauter Mean Diameter (SMD) and heavier mass of fuel molecules than diesel. These along with a lower calorific value of POD resulted in lower power and a higher brake specific fuel consumption than diesel. Furthermore, B50 performs better than B100. [ABSTRACT FROM AUTHOR]