Assessment of the Mechanical Properties of a Diesel Engine Injector

An analytical and experimental model was proposed to determine sac volume pressure changes and fuel doses injected into the diesel engine cylinders. The model takes into account friction forces and identifies the mechanical properties of the injector. The engine performance results were analysed statistically. The results of the Lilliefors, Pearson, Shapiro-Wilk and Jarque-Bera tests provided evidence that, under certain engine operating conditions, the null hypothesis about the compatibility of the measurement data with the normal distribution can be rejected. The measurement uncertainty for the injector needle lift was estimated. The engine was powered with diesel or biofuel. The difference between the measured and the predicted fuel doses amounted to approximately 3%.