Citation :

Sarafaraj Jahangir Mulani, Sachin A. Meshram, Sameer Sheshrao Gajghate, "Experimental and ANN-Based Assessment of Hydrogen-Enriched Diesel Combustion in a Single-Cylinder CRDI Engine Under EGR Operation," International Journal of Mechanical Engineering, vol. 13, no. 7, pp. 80-100, 2026. Crossref, https://doi.org/10.14445/23488360/IJME-V13I7P107

Abstract

The wider use of CI engines is hampered by the requirement to secure both a lower exhaust emission and a better fuel economy, which are connected to a high thermal efficiency, a characteristic for which CI engines are well known. Hydrogen, due to its high flame velocity, wide flammable range and carbon-free property, has become a potential additional fuel for diesel engines. A combined effect of hydrogen enrichment and Exhaust Gas Recirculation (EGR) in the single-cylinder Common-Rail Direct Injection (CRDI) engine, however, should be further evaluated by experiments. The present work investigated the performance and emission characteristics of a water-cooled, four-stroke, single-cylinder compression ignition (CI) engine operated in conventional diesel, hydrogen-enriched dual fuel and hydrogen-enriched EGR (exhaust gas recirculation) mode. The tests were carried out at loads of 0, 3, 6, 9 and 12kg, and the parameters measured were fuel flow rate, torque, Brake Thermal Efficiency (BTE), Brake-Specific Fuel Consumption (BSFC), NOₓ, CO, HC, O₂ and CO₂. Results were obtained which revealed the improvement in the performance of the engine when operated under loaded conditions with hydrogen-assisted combustion. The BTE for 12 kg load in hydrogen-enriched mode without EGR was 34.42%, while it was 22.0% in diesel mode without EGR, and 31.08% for EGR-assisted mode. With the same load range, BSFC in diesel mode was 0.33 kg/kWh, which reduced to 0.31 kg/kWh in the best hydrogen-enriched case without EGR and to 0.28 kg/kWH in the case under EGR-assisted operation. The loaded conditions also exhibited improvement with regards to carbon-related emissions, as CO in the hydrogen-enriched cases without EGR (0.07-0.10%) is lower than in diesel mode (0.19%) and CO₂ is reduced from 8.3% to 7.7-8.0% in several hydrogen-assisted cases. EGR also helped to control NOₓ over a significant portion of the operating range and to maintain the high fraction of efficiency that can be obtained through the hydrogen enrichment process. The overall result of the integrated hydrogen-EGR concept was good in terms of torque response, thermal efficiency, fuel consumption, and important emission characteristics, and it is a promising way to achieve cleaner and more efficient CRDI diesel-engine operation.

Keywords

Hydrogen–diesel dual-fuel combustion, Common-Rail Direct Injection (CRDI) engine, Exhaust Gas Recirculation (EGR), Emission characteristics, Artificial Neural Network (ANN) modeling.

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