K. Muralidharan, M. Rajasankar, K. Arun Balasubramanian and D. Senthilkumar
Abstract
In this research work the impact of fuel injection advance on combustion and gas emissions in a thermal barrier coated diesel engine is examined. The engine is fuelled with lower blends of Honge biodiesel extracted from a non-edible oil feedstock by transesterification process and blended with diesel in various proportions from 0-30% in steps of 5% by volume. The engine combustion chamber components including inlet and exhaust valves, cylinder head and piston crown were coated with yttria stabilized zirconia ceramic material over nickel aluminium alloy bond coat for 300 μm thickness. Fuel injection timing was advanced 4° CA from standard injection timing of 23° CA BTDC by changing the thickness of advance shim. Experimental results confirmed that in coated engine biodiesel blend B15 showed significant reduction in carbon monoxide, unburnt hydrocarbon, smoke emission with slight increase of NOx emission than other fuels tested. At part loads, blend B15 shows significant reduction in CO emission of 18.65%, HC emission of 17.24%, smoke reduction of 29% with slight increase in NOx of 5.38% in injection advance of 27 CA BTDC. At peak loads, B15 experienced emission reduction in CO of 10%, HC of 10.4%, Smoke of 9.85% and slight increase in NOx of 2.94%. Diesel posed higher HRR of 46.25 J/deg and higher cylinder peak pressure of 71.456 bar followed by B15 blend of HRR 43.25 J/deg, peak cylinder pressure 67.33 bar in injection advance.