Performance, Emission and Heat Transfer Optimisation of Variable Compression Ratio Engine Fuelled with Ricinus communis Biodiesel by Taguchi-Gray Rational Approach

Recent research has focused on finding and developing clean alternative fuel such as biodiesel and using innovative methods to minimise harmful emissions and improve engine performance behaviour. In this work, Ricinus communis biodiesel has been prepared from oil through transesterification reaction, and fuel property has been evaluated. The Taguchi L16 orthogonal array experimental design is taken by considering three input control factors as loading (kg), fuel blending (%) and compression ratio, and each input factor has four levels for experimentation. The experimental analysis is done on variable compression ratio diesel engine at each combination of input parameters as suggested by Taguchi experimental design, and thirteen engine responses are recorded. The thirteen engine response are indicated power, break power, break thermal efficiency, break mean effective pressure, break specific fuel consumption, exhaust gas temperature, heat exhaust gas, heat from cooling water, volumetric efficiency, NOx emission, hydrocarbon emission, carbon monoxide and carbon dioxide emission. After experimental work, Gray rational optimisation technique is applied for optimisation of multiple engine responses. The optimisation result shows that the optimised input condition for engine is 8 kg engine load, 10% biodiesel blended diesel and 15 compression ratios. At optimised input condition, in comparison to standard diesel fuel, the engine parameters like break power, break thermal efficiency, break mean effective pressure, heat from cooling water, volumetric efficiency and CO2 emission increased by 2.20%, 3.38%, 3.57%, 13.33%, 1.63%, 0.73% and 4.16% respectively, while exhaust gas temperature, heat exhaust gas, NOx emission, hydrocarbon emission and carbon monoxide emission decreased by 2.50%, 3.07%, 20.68%, 17.64% and 33.33%. The predicted Gray rational grade value at optimised control input condition is 0.715, and the Gray rational grade value of experimental test is 0.740 with error of 0.025. The experimental study established the viability of using 10% Ricinus communis biodiesel with diesel as diesel fuel substitute for diesel engine.