Combined Effects Of Thermal Barrier Coating And Blending With Nanoparticles On Usability Of Algae Biofuel In Diesel Engines

Abstract

The present study explores the combined influence of thermal barrier coating (500μm of YSZ + Al₂O₃) and higher compression ratios (18, 19, and 20) on the performance, combustion, and emissions of a diesel engine using diesel and algae biofuel blends with cerium oxide nanoparticles (BD20CeO₂200 and BD100CeO₂200). Increasing compression ratio (CR) with thermal barrier coating significantly boosts in-cylinder pressure, temperature, and density of air-fuel charge, leading to improved spray characteristics and more efficient combustion of the blended fuel. These improvements are also attributed to the nanoparticles' catalytic effect and high surface-to-volume ratio. A peak brake thermal efficiency of 28.38% was achieved at the lowest brake specific fuel consumption of 0.22 kg/kWh for BD20CeO₂200 at higher CR (20) with thermal barrier coating (500μm). For all the test fuels, at higher CR with thermal barrier coating resulted in a notable reduction in the HC (5.45%), CO (12.6%), and NOx (8%) emissions. Furthermore, engine modification with a thermal barrier coating at higher compression ratios showed superior results compared to the uncoated engine, with a 7% increase in peak pressure, a 6.8% rise in heat release rate, and an 11.36% reduction in ignition delay for BD20CeO₂200. The experimental findings indicate that adding 200 ppm of cerium oxide (CeO₂) nanoparticles as a fuel additive into a small volume (BD20) of the algae biofuel blend, combined with a high CR (≥18) with thermal barrier coating (500μm), significantly enhanced overall engine performance. This fuel blend emerges as a sustainable and practical alternative to conventional fuels.