Modelling of operation of a diesel engine equipped with an all-speed governor

A model of a diesel engine equipped with an all-speed governor is presented in the paper. It is designed for investigations of unsteady movement and transition processes taking places in driving systems of tractors, mobile machines and heavy vehicles during movement starting, stopping and during changing gears under load - using computer simulation methods. The model affords possibilities for simulations of engine operation under changes of engine load and under changes of all-speed governor settings. A diesel engine equipped with an all-speed governor is an automatic control system. The presented model of this system is composed from: a motion equation of an engine mechanical system, a function describing an engine performance as effects of the energy conversion, a function describing a characteristic of an engine fuel feed system and a motion equation of the all-speed centrifugal governor. Conditions of governor motion stability during cooperation with engine have been formulated. The model has been formulated in a dimensionless form. That affords possibility for using the model to movement simulations of vehicles equipped with engines which power is different - directly or after simple modifications. The dimensionless form allows simplifying a describing of signals which are transmitted between elements of model and allows estimate values of model parameters without detailed knowledge about engine and governor constructions. Principles of a model parameters assorting have been presented. This assorting can be done by using an engine performance and conditions of stability in dimensionless forms. A computer program using described model has been written. Numerical simulations results of the processes succeeding sudden changes of the all-speed governor settings, following jumps of engine load and concomitant with harmonic load have been presented.