Effect of Oxy-hydrogen Enrichment into Water-in-Biodiesel Emulsion Towards Performance and Exhaust Emissions of a Diesel Engine
Keywords:
Biodiesel–water emulsion, Brake thermal efficiency, Diesel engine performance, Exhaust emissions, Oxy-hydrogen enrichmentAbstract
This study aims to evaluate the combined effect of water-inbiodiesel emulsions (WBE) and oxy-hydrogen (HHO)
enrichment on diesel engine performance and emissions.
Experiments were conducted on a single-cylinder diesel
engine fueled with B35 (35% biodiesel–65% diesel), WBE5
(5% water-in-biodiesel emulsion), and their HHO-enriched
blends under 1–4 kW loads. Engine performance was
assessed through brake specific fuel consumption (BSFC),
brake thermal efficiency (BTE), and exhaust gas temperature
(EGT), while emissions of NOx, CO, and CO₂ were measured.
Results show that WBE5 reduced NOx emissions by up to
30.2% compared with B35 and improved BSFC by 6.2% and
BTE by 8.4% at 2–3 kW loads. However, CO emissions
increased by about 18% due to lower combustion
temperatures. HHO enrichment improved BSFC and BTE at
light loads (1–2 kW) by up to 2% and decreased CO emissions
through enhanced oxidation, but its influence on NOx was
minimal and diminished at higher loads. Overall, WBE–HHO
dual-fuel operation provides partial advantages, particularly
under light-to-medium loads, offering a feasible pathway
toward cleaner and more efficient diesel engine operation
without major modifications.
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