Influencing mechanism of fuel injection vector on diesel engine torsional vibration

A V8 diesel engine model for coupling simulation between crankshaft dynamics and engine performance using lumped-mass method was established and was calibrated by the experimental data. Simulation on the influencing mechanism of the fuel injection vector on torsional vibration was conducted, and the summation of excitation torque vector was used to evaluate the tortional vibration energy. Results show that adjusting fuel injection mass affects the low frequency range of excitation torque spectrum. Fuel timing affects the higher frequency range and phase of excitation torque spectrum. Excitation torque spectrum can be used to suppress the torsional vibration. The torsional vibration amplitude of 5.5 order is reduced by 21.2%. The trends of summation of excitation torque vector and torsional vibration angle amplitude keep consistently. Summation of excitation torque can be used as the optimization target for torsional vibration suppression.