Development of BS-III CNG Engine for a Light Commercial Vehicle

Environmental degradation is on the rise due to the increased motor vehicle population. One of the strategies adopted to curb deteriorating environmental quality is the use of alternative fuels like Ethanol, Compressed natural gas and Liquefied Petroleum Gas. Natural gas is the world's most plentiful combustible fuel, abundantly available in all the continents. This naturally occurring fuel requires little or no treatment prior to use as compared to liquid petroleum products. Natural gas is also the lowest costing fuel. The use of CNG as an automotive-fuel results in significant reduction in the level of vehicular pollutants CO, HC, NOx, SOx, Pb and PM [1, 2, 3 and 4]. Additionally, the use of CNG results in reduction in the emissions of greenhouse gases (CO₂), owing to the lower Carbon-to-Hydrogen ratio of the methane (CH4), as compared to other hydrocarbon fuels [5, 6 and 7]. This paper describes the development of a 4-cylinder dedicated stoichiometric CNG engine compliant to BS-III Emission Norms for LCV application.