PERFORMANCE AND EMISSIONS TESTING OF GASOLINE AND CNG ON A SI ENGINE

Abstract

Nowadays, increased attention has been focused on internal combustion engine fuels. Compressed natural gas has been introduced as an alternative to gasoline and diesel fuels in many applications. A high research octane number which allows combustion at higher compression ratios without knocking phenomenon and good emission characteristics of unburned hydrocarbons and carbon monoxide are major benefits of compressed natural gas as an engine fuel. In Present work an experimental study is conducted using gasoline and compressed natural gas (CNG) as the main fuel in a 4-cylinder,4-stroke spark ignition Maruti wagon –R engine at different loading conditions. The engine was converted to computer integrated Bi-fueling system and operated separately either with gasoline or CNG. A personal computer (PC) based data acquisition and control system was used for controlling all the operation. A detailed comparative analysis of the Engine performance and exhaust emissions is performed. The variation of performance parameters (BSFC, BTE, and BSEC) and emissions (CO, CO2 and HC) for CNG is compared with gasoline for a wide range of Engine load. The results show that gasoline is having higher BSFC as compared to CNG. Whereas BTE or maximum BTE for gasoline and CNG are almost same. A CO and HC emission of CNG is lower but little more NOX which can controlled with catalytic convertor as compared to gasoline. CNG can be successfully used as an alternative gaseous fuel in SI engine.