Abstract :
Non-road mobile machinery is used for a variety of different operations. The in-use fuel consumption of non-road mobile machinery depends on the actual operation performed, including transient behaviour, rather than the static load distribution commonly used in steady-state-based fuel consumption models. A recent study has shown that during fast transients, measured fuel consumption is up to twice as high as during the corresponding steady-state load conditions. The purpose of this work was to develop a calculation model that includes the transient effects on the overall fuel consumption.
The transient fuel consumption model was based on a semi-static model and extended with transient correction factors for both changes in engine speed and torque. A general conclusion of the work was that fuel consumption could be accurately estimated even during operations that are largely transient in nature. Moreover, the results showed that the model developed for transient fuel consumption could also be applied to emissions of carbon monoxide, hydrocarbons, nitrogen oxides and particulate matter. The average difference between recorded and calculated fuel consumption and emission amounts decreased from approximately 30% for the semi-static model alone down to about 5% when it was extended with the transient correction factors.
