Performance and CO₂ emission of a single cylinder compression ignition engine powered by <i>Khaya senegalensis</i> non-edible seeds fuel blends.

Abstract

This work aimed at investigating blends of <i>Khaya senegalensis</i> biodiesel in a compression ignition engine, attempting to improve engine performance and reduce CO₂ emission compared with conventional diesel. Analysis of System (ANSYS) was used to predict in-cylinder behavior of the fuel. ANSYS SpaceClaim generated the geometric model on which 5° sector and mesh refinement was on ANSYS Internal Combustion Engine Modeler (ICEM). Computational domain of interest lies within the compression and expansion strokes. Experimental validation followed: 5% biodiesel, 95% diesel (B₅); 15% biodiesel, 85% diesel (B₁₅); 25% biodiesel, 75% diesel (B₂₅); pure diesel (D₁₀₀); pure biodiesel (B₁₀₀) in volume proportions. B₁₅ has the highest brake mean effective pressure (BMEP) of 4 bar as load increases. An experimental and numerical comparison reveals pressure declination against speed increment. Ignition temperature fluctuated between 799.76 and 806.256 K for D₁₀₀ and 760.73-790.62 K for B₁₀₀ within 1800-2800 rpm speed limit prediction. Power and brake thermal efficiency (BTE) had parallel load increment with all blends. CO₂ emission on increasing load conditions were 47.01%, 8.07%, 21.72% and 6.06% for B₅, B₁₅, B₂₅, and B₁₀₀ respectively lower than D₁₀₀. Pressure and temperature contours gave proper combustion predicted behaviors. All blends possess replaceable performance potential for D₁₀₀ however, B₅ offers better reliable potentials.