A comparative study on coated and uncoated diesel engine performance and emissions running on dual fuel (LPG - biodiesel) with and without additive

The study was conducted on a partially stabilized zirconia coated single cylinder, four stroke, water cooled and direct injection diesel engine and was modified to use the liquefied petroleum gas (LPG) as the primary fuel and pilot spray of biodiesel with and without Di-Tertiary Butyl Peroxide (DTBP) additive as the secondary fuel. The primary fuel was mixed with air in intake manifold, compressed, and ignited by a pilot spray of secondary fuel. The biodiesel was prepared from palm oil by base catalyst transesterification method. The performance and emission characteristics of coated diesel engine were examined by operating on dual fuel mode (LPG-biodiesel and LPG-diesel) without additive and LPG-biodiesel with additive. The results were compared to uncoated engine running on diesel fuel. The study reveal that, a significant improvement in performance of coated engine operating on dual fuel mode (LPG-biodiesel) with additive by an increase in efficiency of 4.5% and decrease in brake specific fuel consumption of 4.2% at 80% of full load, HC and CO emissions are reduced between 9% and 12% at entire load spectrum compared to uncoated engine operating on diesel fuel. NOx emission is drastically reduced up to 32% for dual fuel with additive compared to without additive in coated engine operation and very close to diesel fuel in uncoated engine operation.