Optimization of biodiesel/2-propanol/1-hexanol blends based on diesel engine performance using combined mixture-process design (CMPD)

Abstract The combined mixture and process design (CMPD)-based optimization tool showed precise prediction and optimized results when there were two or more mixture combinations and one or more process factors investigated. Therefore, in this study, the CMPD method was employed to optimize the mixture components of premixed 20% mango seed methyl ester mixed with 80% diesel (MB20); 2-propanol and 1-hexanol components were optimized with process factor of variable loads. The process factor load was varied from 0 to 100% at 25% intervals, whereas the amount of alcohol was not permitted to exceed 15% by volume in each case. The designed CMPD model optimized the emission parameters such as CO, CO2, O2, HC and NOx to their minimum levels to produce maximum brake thermal efficiency (BTE) from the test engine. The developed optimization model achieved a maximum regression value (R2) of 0.9826 for BTE while CO attained the lowest value (i.e. 0.9254 R2). However, the model optimized BTE, BSFC, CO, CO2, O2, NOx and HC values as 24.31%, 0.452 kg/kw.h, 0.133%, 3.397%, 15.896%, 283.268 ppm and 17.879 ppm, respectively, with the desirability of 0.884. This suggests the optimum fuel combination is 80% MB20, 5% 2-propanol, and 15% 1-hexanol with a 76.086% load.