RE-X options for reducing extra fuel consumption caused by component degradation in industrial diesel engines
Abbasi, Mohib (2026)
Diplomityö
2026
School of Energy Systems, Ympäristötekniikka
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Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi-fe2026061772489
https://urn.fi/URN:NBN:fi-fe2026061772489
Tiivistelmä
This thesis investigates how the degradation of various components in a Stage V non-road diesel engine affects fuel consumption and greenhouse gas emissions, and how repair, refurbishment or remanufacturing strategies can be used to mitigate the effects. This research is motivated by the impact of fuel consumption on the life-cycle environmental performance of diesel-engined non-road mobile machinery and the lack of research examining the link between component wear and expected fuel penalties due to wear while in operation, and maintenance strategies in a circular economy context.
A condition-based maintenance model in Microsoft excel of a typical 120 kW Stage V non-road diesel engine was developed for a 10,000-hour forestry-duty cycle. The charge air cooler (CAC), diesel particulate filter (DPF), selective catalytic reduction (SCR) system and exhaust gas recirculation (EGR) system were modelled. The component degradation was expressed as time-dependent fuel penalties constrained by component-specific penalty limits and adjusted at inspection intervals by repair, refurbishment or remanufacturing actions. Additional fuel consumption, additional well-to-wheel carbon dioxide equivalent emissions and event-based greenhouse gas emissions from interventions were added to the environmental boundary of the model. Economic modelling was not pursued.
The findings indicate that, for all four components, the highest cumulative incremental greenhouse gas emissions (within the model boundary) were associated with the business-as-usual scenario of no action when components have degraded, while the lowest cumulative emissions were incurred with the always remanufacturing strategy. The always-inspect strategy with constrained level of intervention produced lower greenhouse gas emissions than business-as-usual and always repair but did not perform better than always refurbishment or always remanufacturing. Variation was noticed at the component level, under the central residual case, the cumulative burden was highest for CAC degradation, followed by DPF and EGR, and was lowest for SCR.
The results suggest that fuel penalties caused by degradation can have a large cumulative environmental impact and that intensive restorative actions may be warranted in terms of the use-phase emissions they defer. But the model should be considered a comparative environmental decision-making tool, rather than a calibrated model of a real engine, because it does not address economic considerations, interactions between components, or contain detailed empirical data for all intervention processes.
A condition-based maintenance model in Microsoft excel of a typical 120 kW Stage V non-road diesel engine was developed for a 10,000-hour forestry-duty cycle. The charge air cooler (CAC), diesel particulate filter (DPF), selective catalytic reduction (SCR) system and exhaust gas recirculation (EGR) system were modelled. The component degradation was expressed as time-dependent fuel penalties constrained by component-specific penalty limits and adjusted at inspection intervals by repair, refurbishment or remanufacturing actions. Additional fuel consumption, additional well-to-wheel carbon dioxide equivalent emissions and event-based greenhouse gas emissions from interventions were added to the environmental boundary of the model. Economic modelling was not pursued.
The findings indicate that, for all four components, the highest cumulative incremental greenhouse gas emissions (within the model boundary) were associated with the business-as-usual scenario of no action when components have degraded, while the lowest cumulative emissions were incurred with the always remanufacturing strategy. The always-inspect strategy with constrained level of intervention produced lower greenhouse gas emissions than business-as-usual and always repair but did not perform better than always refurbishment or always remanufacturing. Variation was noticed at the component level, under the central residual case, the cumulative burden was highest for CAC degradation, followed by DPF and EGR, and was lowest for SCR.
The results suggest that fuel penalties caused by degradation can have a large cumulative environmental impact and that intensive restorative actions may be warranted in terms of the use-phase emissions they defer. But the model should be considered a comparative environmental decision-making tool, rather than a calibrated model of a real engine, because it does not address economic considerations, interactions between components, or contain detailed empirical data for all intervention processes.