Keywords: energy efficiency, energy conversion, direct injection diesel engines, modifications, emission norms, combustion chamber, fuel cam, fuel injection, EGR, exhaust gas recirculation, engine emissions, NOx emissions, vehicle emissions
Development of automotive DI diesel engine to comply with stringent emission norms
Relatively lower fuel energy cost, higher fuel conversion efficiency and ability to take higher loads are the attracting features of direct injection diesel engines. However, diesel engines are still posing the challenges to both researchers and manufacturers in terms of high soot and NOx emissions. To overcome these difficulties, small diesel engine manufacturers are resorting to either upgrade their existing diesel engines to comply with the periodic revision in emission norms. A research work is taken–up to develop engines for complying with the stringent emission norms. To achieve the objective, an existing diesel engine is suitably modified in combustion chamber, fuel cam, fuel injection system and employed EGR technique. Performance optimisation tests are conducted on both engine and chassis dynamometers following the standard procedures of loading and vehicle driving cycles. 10% EGR is found to be optimum for engine performance and NOx emission reduction to achieve BS–III emission norms. With the design modifications incorporated added with 10%EGR about 85%, 32% and 75% reduction in CO, HC + NOx and PM emission respectively are obtained.