Effect of CCV and OCV system in Heavy Duty CNG Engine on the Particulate Emissions

Due to increasing pollution and climatic cries, newly implemented BS VI emission norms in India have stressed on the reduction of emission. For which many automobiles have been shifted to alternate fuels like CNG. Also, Indian Automotive market is fuel economy cautious. This challenges to focus on improving fuel economy but without increase in emissions. Crankcase blowby gases can be an important source of particulate emission as well as other regulated and unregulated emission. They can also contribute to the loss of lubricating oil and to fouling of surface and engine components. Closed Crankcase Ventilation (CCV) or Open Crankcase Ventilation (OCV) is capable to reduce the particulate emissions by removing the oil mist that caused mainly due to blowby in combustion chamber. This paper work is focused, to measure the effect of the CCV and OCV systems on the engine out emissions, primarily on the particulate emissions. A comparative analysis of these crankcase ventilation systems is made by monitoring various parameters, like crankcase pressure, intake air temperature and pressure, exhaust temperatures, etc. to analyze the effectiveness of these systems for reduction in particulate emissions. Key Words: BS VI, CNG, CCV, OCV, particulate emission.