2026-10-11T21:48:12Z https://www.scidb.cn/oai

10.57760/sciencedb.45630 2026-08-07T10:19:58Z

2026-08-07 Thermodynamic and Environmental Assessment of Hydrogen-Microalgae RCCI Combustion: A Unified Exergy, Performance, and Emission Analysis doi:10.57760/sciencedb.45630 en Despite the potential of Reactivity Controlled Compression Ignition (RCCI) to mitigate carbon intensity, significant gaps remain in the integrated thermodynamic assessment of hydrogen-microalgae systems, particularly concerning load-dependent irreversibilities. This study evaluates a B20 algal methyl ester (HRF) and hydrogen (LRF) framework across 25–100% loads with hydrogen premixing ratios (PR) up to 55%. The research novelty lies in providing a unified exergy-combustion-performance-emission analysis for this specific fuel pairing, quantifying the "thermodynamic price" of emissions reduction through the Exergy Depletion Factor (EDF).The methodology involved experiments on a single-cylinder diesel engine at a constant 1500 rpm using a 23° CA bTDC pilot injection and port-injected hydrogen. Thermodynamic assessments were performed against a standard ambient dead state to calculate exergy destruction and entropy generation. Results reveal a load-dependent paradigm shift: at low loads, hydrogen’s auto-ignition resistance retarded peak pressure by 3° CA, whereas at 100% load, its rapid flame velocity advanced combustion by 3° CA. Environmentally, PR50 reduced NO and HC emissions by approximately 75% and 80%, respectively. However, a critical thermodynamic trade-off was observed; while Brake Thermal Efficiency (BTE) improved by 11.5% at moderate PRs, the overall exergy efficiency decreased from 8.07% to 4.87% at full load. This decline, coupled with a 294.7% spike in entropy generation, highlights significant irreversibilities caused by chemical exergy losses in unburned exhaust species. hydrogen-microalgae; RCCI; exergy Nikhil Bhave PUBLIC https://creativecommons.org/licenses/by-nc/4.0/ dataset Science Data Bank