Characterization of infield duty cycles and exhaust emissions from diesel powered off-road heavy-duty equipment

The objective of study was to design, develop, and evaluate techniques to measure exhaust emissions from diesel-powered off road equipment. Emissions data was collected from a Komatsu hydraulic excavator and a Caterpillar track-type tractor.; For the excavator, data was logged during in-field operation, and test cycles were created on a dynamometer test bed using this data. For the tractor, on-board emissions measurement equipment collected mass emissions rate data in field.; Vast differences were found between transient and 8-mode brake-specific test results. Transient cycle HC, CO, CO₂, NO, and PM emissions were 50%, 65%, 10%, 35%, and 50% lower than 8-Mode results, respectively. Data collected from the tractor during a 360 second test was 5062 g/cycle CO₂, 67.7 g/cycle NO_x, and 0.349 g/cycle DPM.; The study concluded that exhaust emissions are vehicle and task specific in nature, and that 8-Mode test results lack the ability to realistically estimate actual in-use engine emissions.