Optimization of diesel engine parameters using Taguchi method and design of evolution
The objective of this work is to optimize the control parameters of the direct injection (DI) single cylinder diesel engine with respect to NOx (Oxides of Nitrogen) and fuel emissions through experimental investigations and Taguchi method. A single cylinder 5.2 kW diesel engine was selected for this experiment. Five parameters such as clearance volume, valve opening pressure, nozzle-hole diameter, static injection timing and load torque were varied at four levels and the responses such as NOx emissions and fuel economy were recorded. The optimum values of the response variables could be predicted using S/N ratio and optimum combination of control parameters were specified. Results of confirmation tests showed good agreement with predicted results. Thus the relationship between the diesel engine operating parameters with NOx and b.s.f.c (brake specific fuel consumption) could be understood using Taguchi method of experimental design.
Optimization of diesel engine input parameters running on Polanga biodiesel to improve performance and exhaust emission using MOORA technique with standard deviation
ABSTRACT Fast exhausting fossil fuel reserves and high rise in the air pollution levels due to combustion of these fuels bound us to discover some cleaner and environment-friendly fuels for the engines. Biodiesel from edible and non-edible seed oils has been identified as a better alternate of the diesel fuel in engines with a little sacrifice in terms of power output but with an improvement in exhaust emissions. The aim of the present research work is to optimize the input parameters of diesel engine running on Polanga biodiesel to improve performance and exhaust emissions. The input parameters selected for optimization are fuel injection timing, fuel injection pressure, Polanga biodiesel blend, and engine load with respect to brake thermal efficiency, brake specific fuel consumption, hydrocarbon emission, smoke opacity, and emission of nitrogen oxides. Relative weights of the response variables were calculated by standard deviation. The optimum combination of input parameters was obtained by Taguchi-based Multi-Objective Optimization by Ratio Analysis. Experiments were performed according to Taguchi’s L16 orthogonal array in a random manner in which three replicates of each experiment were noted. The optimum combination of input parameters for maximum performance and minimum exhaust emissions found to be as fuel injection timing 27° bTDC, fuel injection pressure – 220 bar, biodiesel blend – B40, and engine load – 60%. The optimum values of the response variables, at the obtained optimum combination of input parameters, were predicted by Taguchi method and then verified experimentally and a good relation was found between them. These optimum values found to be as brake thermal efficiency – 36.351%, brake specific fuel consumption – 0.322 kg/kW-h, hydrocarbon emission – 2.193 ppm, smoke opacity – 80.925 HSU, and NOx emission – 690.987 ppmv.
A PRACTICAL APPROACH TO TRUCK NOISE REDUCTION
An approach is described for reducing the drive-by noise of a 14-liter diesel-engined truck which involves a combination of conventional noise reduction techniques. The combustion and mechanical exciting forces within the engine are respectively lowered by turbocharging and low-noise pistons, coupled with a small reduction in the rated speed. The resulting noise is largely attenuated by employing simple shielding attached with isolation mounts to form a tunnel around the engine. A reduction of drive-by noise from 92 1/2 dBA to 82 dBA has been demonstrated with this approach. A level of 80 dBA was achieved with additional silencing and shielding of the non-engine noise sources. A method is appended for calculating the radiated combustion and mechanical noise levels from an engine.