oa Experimental Investigation of Single Cylinder Diesel Engine by Using Cetane and Octane Based Fuels

The global rise in energy demand has intensified concerns over vehicular emissions and their impact on climate change. This study investigates the comparative performance and emission characteristics of four fuels—Diesel, Liquefied Petroleum Gas (LPG), Neat Bio-Diesel (Mustard-based), and Gasoline—using a single-cylinder, four-stroke engine operated at a constant speed of 1500 rpm under eight load conditions (0.25 to 2.00 kW). Experiments were conducted both on the stock diesel engine and on the same engine modified for spark ignition operation. Key performance indicators such as thermal efficiency, fuel consumption, and emissions (HC, CO, NOx) were measured under steady-state conditions. Outcome indicated that LPG produced the lowest HC and CO emissions, highlighting its potential as a clean-burning fuel. Bio-Diesel exhibited moderate emissions but recorded the highest NOx levels, likely due to its higher oxygen content. Diesel demonstrated the best fuel economy (lowest SFC) but higher emissions compared to LPG and Bio-Diesel. Gasoline achieved the highest thermal efficiency but exhibited the highest HC and CO emissions, making it the least environmentally favorable option. The findings support the viability of LPG and Bio-Diesel as cleaner alternatives to conventional Diesel and Gasoline, with trade-offs in fuel economy and NOx requiring further optimization.