Multi-Response Optimization of Variable Compression Ratio CI Engine Using Grey–Taguchi Method

The quest for the development of alternative fuels as an economical and efficient substitute for fossil fuels has become the need of the hour. This work presents multi-response optimization of process parameters in variable VCR CI engine powered by various blends of plastic pyrolysis oil, an alternative fuel under study. Brake power, BSFC, exhaust temperature and brake thermal efficiency are studied by varying compression ratio, load and blend. The experiments were conducted using Taguchi L9 orthogonal array, and the multi-performance characteristics were used in generating Grey relational grade. The optimized combination that results in higher brake power, higher brake thermal efficiency, lower SFC and lower exhaust temperature is obtained and verified through a confirmation test. The validation showed an improvement in Grey relational grade by 0.2768. The results from ANOVA revealed that Grey relational grade is mostly influenced by load (65.71%) followed by compression ratio (19.01%) and blend (6.87%).