Combustion, performance, and emissions of a compression ignition engine using Pongamia biodiesel and bioethanol

Area of Science:

• Renewable Energy
• Combustion Science
• Environmental Engineering

Background:

• Growing concerns about fossil fuel depletion drive research into alternative fuels like biodiesel.
• Biodiesel, derived from vegetable oils, faces challenges including reduced engine performance and increased nitrogen oxide (NOx) emissions.
• Ethanol, a biofuel, is explored as an additive to mitigate these drawbacks.

Purpose of the Study:

• To experimentally investigate the effects of adding ethanol to Pongamia biodiesel-mineral diesel blends in a diesel engine.
• To evaluate the impact of varying ethanol concentrations (5%, 7.5%, 10%) on engine performance and emissions.
• To determine the optimal ethanol blend for improved efficiency and reduced pollutant output.

Main Methods:

• Ethanol was produced from cashew apple juice via fermentation.
• Experiments were conducted using a B20 Pongamia biodiesel blend (20% biodiesel, 80% mineral diesel) with varying ethanol volumes (5%, 7.5%, 10%).
• Engine performance (brake thermal efficiency, brake-specific energy consumption) and emissions (NOx, CO, hydrocarbons, smoke) were measured under different load conditions.

Main Results:

• The B20 biodiesel blend with 7.5% ethanol demonstrated higher brake thermal efficiency compared to pure B20.
• This blend also exhibited lower brake-specific energy consumption than pure B20.
• Significant reductions in emissions, including oxides of nitrogen, carbon monoxide, hydrocarbons, and smoke, were observed with the 7.5% ethanol blend.

Conclusions:

• Ethanol addition to Pongamia biodiesel blends can enhance diesel engine performance.
• A B20 Pongamia biodiesel blend with 7.5% ethanol is effective in improving brake thermal efficiency and reducing brake-specific energy consumption.
• The optimal ethanol blend significantly curtails harmful emissions, offering a more sustainable alternative fuel option.