Numerical and experimental investigations of optimal fatty acid methyl ester hybrid for enhanced engine performance and emission mitigation in the conventional compression ignition strategy.

Abstract

The utilization of petroleum-based diesel fuel to power compression ignition (CI) engines has been hampered by inefficient combustion process resulting in unsatisfactory engine performance and emission of hazardous gases. Fatty acid methyl ester (FAME), due to its renewability, biodegradability, and environmentally friendly emissions, has been acknowledged as a viable alternative fuel for CI engines. The application of waste cooking oil (WCO) as feedstock for FAME production did not conflict with food chain, guarantees appropriate disposal of used vegetable oil, and prevents contamination of aquatic and terrestrial habitats. The FAME was produced by transesterification of WCO samples collected from restaurants, catalyzed by calcium oxide derived from chicken eggshell waste powder subjected to high temperature calcination. Properties and fatty acid (FA) composition of the FAME were determined, the fuel used to power an unmodified CI engine, and measure the performance and emission characteristics experimentally. Numerical techniques, including, matrix laboratory, response surface methodology, Taguchi orthogonal, artificial neural network, and multiple linear regression were utilized to unearth the optimal FAME candidate, determine the properties, FA composition, performance and emission characteristics of the newly generated FAME and were found to agree with experimental results. It was discovered that FAME candidate with a concentration of palmitic acid of 36.4 % and oleic acid of 59.8 % produced improved brake thermal efficiency and brake mean effective pressure as well as reduced fuel consumption, and other regulated emissions.