Experimental studies on the effect of TBC piston in a dual-fueled diesel engine

Oxy-hydrogen gas (HHO) is a carbon-clean alternative fuel like hydrogen and is composed of hydrogen and oxygen in the ratio of 2:1. The significant properties of hydrogen (which is present in HHO) such as high octane rating, better mixing characteristics, high diffusivity, high flame speed also ensure its possible use to run a compression ignition (CI) engine in dual fuel mode. On the other hand, the application of thermal barrier coatings (TBCs) to engine components may reduce thermal fatigue, and the heat loss to the surroundings. In this experimental study, the combined effect of HHO gas on the combustion, performance, and emission characteristics of a dual-fuel diesel engine fitted with two different thermal barrier coated (TBC) pistons was experimentally investigated. Commercially available D2 quality petro-diesel (D100) and a blend composing 20% Jatropha and 80% D100 named as JME20 were used as pilot fuels, while the HHO gas was used as inducted fuel in dual-fuel operation. The experiments were carried out in a single cylinder, four storke, air-cooled, stationary type direct injection (DI) diesel engine fitted with the uncoated and coated pistons were operated in two different dual operations viz., D100 + HHO and Opt.JME20 + HHO. Two separate pistons were used to coat its top crown surface with Yttria-stabilized zirconia (YSZ) and YSZ + CeO2. The results obtained for the combustion, perfor-mance, and emission parameters of the dual fuel diesel engine fitted with the TBC piston and run in dual fuel operation of D100 + HHO and Opt.JME20 + HHO were evaluated, analyzed, and compared with those of the baseline data. The results revealed that the brake thermal efficiency of Opt.JME20 + HHO run in dual-fuel operation was found to be higher by about 5.9% compared to that of the baseline data at full load, for the YSZ + Cerium-oxide (CeO2) coated piston-fitted engine by minimizing the heat loss to the surroundings. Similarly, the maximum carbon monoxide (CO), unburnt hydrocarbon (HC), and smoke emissions with the YSZ + CeO2 coated piston fitted engine operation in dual fuel mode with Opt.JME20 + HHO was found to be lesser by about 44.1%, 46.7%, and 21.5%, respectively compared to that of the baseline data at full load.