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As vehicle emission standards are becoming increasingly stringent worldwide, the application of a Diesel Particulate Filter to trap particulate matter is state of the art in diesel engine- powered vehicles and equipment. Initially, the Diesel Particulate Filter was introduced in India with the BS6 emission implementation. A transfer of the series-proven emission technology from Europe to India is a reliable base while it requires significant adaptations towards an affordable solution for the Indian boundary conditions. This paper explains methods used to arrive at a robust solution considering the typical Indian driving cycles, climate conditions and segment-specific demands. With catalyst protection integrated in the method and a robust model-based exhaust temperature control, a complete closed-loop approach of DPF regeneration is achieved.

Major share of Small Commercial Vehicles (SCV) applications is operated in city conditions with frequent stops and short driving distance. Drivers will often operate these SCV with loads that exceed their rated specifications. Such driving profiles are particularly observed in food, e-commerce delivery, garbage collection vehicles which are driven inside the city. During Diesel Particulate Filter (DPF) regeneration events in these conditions, it is a challenge to maintain light-off temperature of oxidation catalyst. This may lead to prolonged regeneration durations with multiple regeneration interrupts and poor regeneration efficiency. Frequent engine start operations and lower passive regeneration result in a low regeneration interval. The extended DPF regeneration duration in combination with a low regeneration interval will result in high oil dilution. The study focuses on identifying such driving profiles and defining counter measures to improve the regeneration performance.

Based on the fuel consumption analysis methods published on last year's SETC [1], we compared fuel economies of a typical 125cc production motorcycle equipped with either electronic (port) fuel injection (EFI/PFI) engine management system (EMS) or constant vacuum carburetor (Carb). In addition to earlier discussed PFI results, stationary engine map measurements of fuel consumption on an engine dynamometer (dyno) were conducted for the Carb engine. The powerful development tool of fuel consumption test cycle simulation uses these stationary engine dyno results to calculate fuel consumption of real transient vehicle operation. Here it was employed to assess economy of both fuel system configurations under different driving conditions. Besides the Indian Driving Cycle (IDC) and the World Motorcycle Test Cycle (WMTC), we investigated real world drive patterns typical for emerging markets in terms of a Bangalore urban cycle and a Malaysian suburban cycle.

Fuel entry into oil sump dilutes oil and affects its tribological properties, leading to increased engine wear and failure. Higher oil levels can also lead to uncontrolled combustion and unintended vehicle acceleration. In modern BS6 Diesel engines equipped with Diesel Particulate Filters (DPF), the late post injections are a major source of oil dilution. Other sources of fuel in oil dilution are pump failure and improper geometric sealing of moving parts. In vehicles with NOx Storage Catalyst (NSC) installed, the rich mode would also have a high share in the oil dilution. The SAE paper addresses ways to reduce fuel entry rate from post-injections without compromising the DPF performance. The accumulated soot is regenerated at high exhaust temperature. The high exhaust temperature is achieved by introducing late post injections (PoI1) continuously throughout the regeneration duration (approximately 20 to 30 mins).