Effects of high cetane diesel on combustion, performance, and emissions of heavy-duty diesel engine

Fuel economy improvement and reducing exhaust emissions are drivers for advancement in engine technology and fuel quality enhancement. The latest generation diesel engine uses a high pressure common rail fuel injection system and after-treatment devices such as selective catalyst reduction (SCR) and diesel particulate filters (DPF) to meet the stringent emission norms. The performance of engine can be further improved by using better quality fuel than the minimum requirement. Fuel quality improvement can be achieved through modifying blending components and/ or using additives. This study investigates the effect of high cetane diesel on the performance and emission behavior of SCR fitted heavy-duty engines. Normal diesel is doped with diesel multi-functional additives containing cetane improver, and thereby cetane number enhanced to 55 from 52. Fuel consumption and exhaust emission were evaluated over the European stationary cycle (ESC) under the controlled test cell conditions. The fuel consumption with the high cetane diesel was 0.5% lower; CO, HC, and NOx emissions were lower by 12%, 6%, and 8% respectively over the ESC. This paper also highlights mode-wise engine performance, emissions, noise, and combustion behavior of the engine while using a cetane improver in diesel over the ESC cycle. Noise level reduced by 1 dB in the wide-open throttle performance tests when the cetane number increased by 3 units.