Development of the Electrically Controlled Off-Road Small Diesel Engine below 19kW 2023-01-1844
In these days, not only low exhaust emission but also carbon dioxide reduction is required to achieve carbon neutrality toward resolution of climate change. Though examination of electrification and decarbonized fuel is progressing, industrial machines have issues for high load factor and infrastructure development. Therefore, trends of off-road powertrain are expected to be diversified depending on usage environment or applications. As a result, in terms of diesel engines below 19 kW, it should be the best way for satisfying the social needs to develop new diesel engines which have high environmental performance by optimizing engine combustion.
In the case of diesel engines below 19 kW, it is difficult for the engines to adopt the direct injection (DI) combustion system and the common rail system (CRS). The fuel spray of these small displacement engines by DI or CRS easily attaches the wall surface of combustion chamber due to the small bores and causes increasing fuel consumption. Accordingly, the indirect injection (IDI) combustion system by mechanical injection control is mainstream about below 19 kW. These engines’ fuel injection depends on engine speed, so it cannot be said that their fuel amount and timing are optimized in each engine speed.
The electrically controlled fuel injection system optimal for the small IDI diesel engines was developed. This system enables the engines to achieve a high balance between low fuel consumption and low exhaust emission without changing their size from previous ones.
This paper introduces the approach how the IDI combustion with the electrically controlled fuel injection system is evolved and how to improve durability about this new combustion system in order to highly achieve both low exhaust emission and low fuel consumption.
Citation: Fujita, K., Mochizuki, H., Kobayashi, Y., and Onishi, T., "Development of the Electrically Controlled Off-Road Small Diesel Engine below 19kW," SAE Technical Paper 2023-01-1844, 2023, https://doi.org/10.4271/2023-01-1844. Download Citation
