Performance and Emission Analysis of Lemongrass Biodiesel in Diesel Engines at Varied Compression Ratios: A Novel Exploration

Abstract

This study investigates the influence of lemongrass biodiesel on diesel engine performance under varying compression ratios (CRs). Tests conducted at CRs of 16, 17 and 18 unveil an intriguing trend: higher ratios enhance lemongrass biodiesel's effectiveness. With increasing CR, brake-specific fuel consumption registers a decline from 0.48 kg/kWh to 0.38 kg/kWh, indicative of improved fuel efficiency. Notably, B20, a blend comprising 20% lemongrass biodiesel, demonstrates a notable 9.03% surge in brake thermal efficiency compared to conventional diesel at CR 18. However, augmented CR prompts an increase in nitrogen oxide emissions (690 ppm) for B20 at CR 18. Concurrently, carbon monoxide and unburnt hydrocarbon emissions experience average reductions of 27.27% and 16.66%, respectively. This study underscores lemongrass biodiesel's potential as a viable alternative fuel, revealing its performance gains under heightened compression ratios. While enhanced efficiency and thermal output are evident, the trade-off between increased nitrogen oxide emissions and reduced carbon monoxide and hydrocarbon emissions necessitates a balanced assessment of its environmental implications.