In view of BS-VI emission norms implementation in Commercial Vehicle (CV) application, the emissions are not only confirmed in standard condition but also in non-standard condition including different combinations of ambient temperature and pressure especially for checking the emission in WNTE cycle. However, achieving the emissions in different environmental conditions require physical emission calibration to be performed in those conditions. Hence, engine must be calibrated in climatic test chambers to ensure emission in different climatic conditions leading to multifold increase in the calibration effort.
With addition of BS-VI emission regulation, After Treatment System (ATS) is a mandatory requirement to reduce the tail pipe emissions. Efficient functioning of ATS requires enough heating to convert the engine out emissions. Vehicle level Real Drive Emission (RDE) measurement without Conformity Factor (CF) limitation are added as an important legislative requirement. However, in commercial vehicle application the single engine configuration is used for different vehicle applications. These vehicles are having different speed and load profiles and varying ATS layouts. Therefore, robust thermal measures are required to ensure adequate heating of ATS under various climatic condition with worst case of ATS layout and vehicle load profile. The thermal measures stress the engine components to work on design limits, thus engine must operate steadily and provide adequate heat to ATS under extreme climatic application. This calls for a robust engine component protection in varying climatic conditions.
In this paper a calibration methodology is discussed to calibrate the medium duty diesel engine for robust component protection in different climatic conditions (varying environment pressure and temperature), also to calibrate robust thermal measures to ensure sufficient heating of ATS while minimizing the efforts applied in climatic test bed calibration and achieving significant time reduction in vehicle validation. Hence with this approach a considerable cost and vehicle validation time could be saved with providing robust calibration.