Energy Conversion and Management: X (Apr 2024)
Experimental study on performance and emissions from Prosopis Juliflora biodiesel blends with diethyl ether additives
Abstract
The purpose of this research is to look at performance and emission characteristics of Ethiopian Prosopis Juliflora biodiesel (JFB) blended with diethyl ether (DEE) additive in varying proportions. The experiment includes testing different biodiesel blends and DEE additive concentrations, namely D100, B100, B20DEE5, B20DEE10, B20DEE15, and B20DEE20. FT-IR (Fourier transform infra-red) analysis was employed to investigate whether necessary functional groups for a biodiesel were present. Rheometer analysis was employed to investigate how shear rate and temperature affect the shear stress and viscosity of blended fuels employed. Results show that D100 exhibits the highest brake thermal efficiency (BTE) across the load range, while B100 has the lowest. Although DEE blended fuels have lower BTE than diesel, the results are comparable. Notably, at 50 % load, B20DEE10 achieves a BTE of 31.4 %, closer to D100 at 36.7 %. Brake-specific fuel consumption (BSFC) decreases as load increases up to 50 %. While BSFC for JFB, B20, and blended fuels is higher than D100 across all engine loads, B20DEE10 shows a comparable result of 203 g/kWh versus 181 g/kWh for D100 at 50 % load. Emission levels for CO2, HC, and CO are higher for diesel compared to blended fuels, with NOx being lower for D100 and all DEE blended fuels. DEE’s higher Cetane rating and latent heat of evaporation along with shorter ignition time and faster heat release rate seems to result in lower NOx emissions, especially for medium to higher loads. At full load, B20DEE10 exhibits the lowest smoke opacity value. Additionally, FT-IR analyses confirm the presence of necessary functional groups in biodiesel and the rheological analysis shows a decrease in viscosity with increasing temperature and a shear-thinning behavior for JFB across a range of shear rates with a viscosity ranging from 203.4 to 47.5 mPa.s, with a shear rate range of 10–150 s−1.
