Studying the effect of diesel fuel properties on emissions from engines with the fuzzy regression method

It has been studied how to construct the fuzzy linear regression model and to calculate the fuzzy regression coefficients in the paper. Based on above work, selecting diesel fuel properties: density, polyaromatics, cetane number and back end distillation as the independent variables, and engine emissions: total hydrocarbons (HC), carbon monoxide (CO), nitrogen oxides (NOx) and particulate matters (PM) as the dependent variable respectively, the fuzzy linear regression models are obtained. The fuzzy regression coefficients are calculated with the simplex method. Restrictions on the fuzzy center and fuzzy width of the fuzzy regression coefficient are put forward too. The results show that all of the fuzzy linear regression equations can present correctly relationship between the independent variables and the dependent variables. It is feasible to study the effect of diesel fuel properties on engine emissions with the method.