Experimental Investigation of Performance and Emission Parameters of a Small Diesel Engine Using CNG and Biodiesel

The use of compressed natural gas (CNG) in diesel engines can be considered one of the optimum alternative solutions for reducing fuel consumption rate and pollutant emissions components from diesel engine. CNG can ideally replace diesel fuel; a 90% diesel was replaced by CNG, while remain 10% was used as a pilot fuel. Biodiesel was used as a pilot fuel in this research. Methyl ester of sunflower oil was the main component of the biodiesel that used in this project. The results of the engine tests on the basis of ECR-49 standard showed that increasing biodiesel percentage in pilot fuel compound resulting in reducing the combustion chamber peak pressure, exhaust engine temperature and ignition delay. The inherent biodiesel property CO and NOx emissions were seemed to be decreased; however UHC was found to be increased, this was due to incomplete combustion of B10% fuel compound.