Prediction model of injection quantity of high pressure common rail fuel system

  Objectives  In order to provide the basis for accurate control of diesel engine fuel injection quantity, a method was proposed to establish the main injection quantity prediction model with input parameters as dwell time, common rail pressure and main injection pulse width for the pre-main injection mode.

  Methods  AMESim simulation model was used to conduct simulation experiments and then collect data. Based on the data, the relationship between the dwell time and the main injection volume under single working condition was obtained. On this basis, the influence of common rail pressure and main injection pulse width on the model coefficient was introduced to build a complete multi-working condition main injection quantity prediction model. Multiple input parameter combinations were used to verify the accuracy and reliability of the prediction model of main injection quantity fluctuation.

  Results  The results show that the root-mean-square error (RMSE) of the scheme of multi-working condition main injection quantity prediction model is 1.443 mm³. It can reduce the experiment amount required for modeling from n³ orders of magnitude to n² orders of magnitude.

  Conclusions  The proposed prediction model has sufficient accuracy, which is of great significance for engineering application of model-based fuel injection control.