Survey performance and emission parameters of diesel engine powered by diesel oil and fatty acid methyl esters using fuzzy logic techniques

Natural environment protection and preserving natural resources of our planet are very important issues. This study deals with the issues related to use of fatty acid methyl esters to power combustion engines and its impact on the performance of selected drive units. The study objects are motor vehicles equipped with 81 kW self ignition engine and Common Rail injection system. The tests were divided into two steps, that is, initial tests and main tests. Initial tests involved identification of physical-chemical characteristics of the analyzed mixtures. Fuel mixtures with a higher content of fatty acid methyl esters had a higher cetane number by about 4% and a higher viscosity index by about 12%. Main tests involved measurement of ten performance parameters of the drive units such as: power, torque, noise emission, content of solid particles in exhaust and the composition of exhaust gases (oxygen, carbon monoxide, hydrocarbons, nitric oxides and the air excess coefficient). The tests results were used for development of a resultant model for assessment of the study object operation. The model was verified by means of fuzzy logic. The presented method of fuzzy mean diagrams was a tool for assessment of the impct of fatty acid methyl ester additives in fuel on performance of drive units of the analyzed transport means. The assessment shows that the composition of the fuel mixture had the greatest impact on the oxygen and carbon dioxide criterion, and the smallest on the particulate parameter. Their grades were respectively 0,1353 and 0,0755 and 0,0002. The analysis showed the legitimacy of using these fuel mixtures.