EXPERIMENTAL INVESTIGATION ON THERMAL BARRIER-COATED DIESEL ENGINE USING ANTIOXIDANT-DOPED ORANGE PEEL OIL BIODIESEL

The performance and emission characteristics of pure orange peel methyl ester (OPME) were examined in this study to determine the impact of antioxidant additions. To enhance engine performance and reduce emissions, butylated hydroxytoluene (BH) was added to the prepared methyl ester at different concentrations of 250, 500, 750 and 1000ppm. The blended biodiesel was tested in a compression ignition (CI) engine as well as a ceramic-coated engine. The conventional engine in this study was later converted into a low-heat rejection engine by coating Yttria stabilized zirconia (YSZ) on the piston crown. The coating on the piston was done by the traditional atmospheric plasma spray (APS) method. The tests were conducted by changing the load of the engine from 0% to 100% with a 25% interval. The readings obtained from conventional and coated engines using BH-dosed OPME were compared with diesel-operated conventional engines. Specifically, at 750 ppm BH dosage, brake thermal efficiency (BTE) increases by 3.04%, while brake specific fuel consumption (BSFC) decreases by 15.3%. Moreover, carbon monoxide (CO) emissions decrease by 36.6%, and hydrocarbon (HC) emissions decrease by 39.1% compared to conventional diesel operation. These findings highlight the efficacy of antioxidant-doped OPME in enhancing engine efficiency and reducing harmful emissions, making it a promising alternative fuel for sustainable transportation.