Numerical investigation on NOx emissions and thermal performance of hydrogen/ammonia fueled micro-combustors with periodic wall structures

Renewable Energy, Journal Year: 2025, Volume and Issue: unknown, P. 122347 - 122347

Published: Jan. 1, 2025

Language: Английский

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Numerical Analysis of Combustion and Thermal Performance of a Bluff-Body and Swirl-Stabilized Micro-Combustor with Premixed NH3/H2/Air Flames

Energies, Journal Year: 2025, Volume and Issue: 18(4), P. 780 - 780

Published: Feb. 7, 2025

This research presents a novel bluff-body and swirl-stabilized micro-combustor fueled by an ammonia/hydrogen mixture, aimed at enhancing flame stabilization for zero-carbon micro-combustion-based power generators. Employing numerical simulations, the study examines effects of geometry, inlet mass flow rate, vane angle, combustor material on combustion thermal efficiencies. Key findings demonstrate that shape significantly influences outcomes, with cone-shaped designs showing lowest radiation efficiency among tested geometries. The identifies optimal rate 9×10−6 kg/s, which achieves 99% superior uniformity in mean outer wall temperature. While variations primarily affect NO emissions temperatures, they have minimal impact efficiency. Further analysis reveals adjusting angle from 15 to 60 degrees improves temperature uniformity, efficiencies, while also reducing emissions. 60-degree is particularly effective, achieving approximately 44% Additionally, selection plays pivotal role, silicon carbide outperforming others delivering optimized (approximately 910 K), (38.5%), most uniform Conversely, quartz exhibits lower performance metrics.

Language: Английский

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Thermal performances investigation on an ammonia-fuelled heat-recirculating micro-combustor with reduced chemical mechanism

Applied Thermal Engineering, Journal Year: 2023, Volume and Issue: 236, P. 121685 - 121685

Published: Oct. 2, 2023

This study addresses the challenges in utilizing ammonia as a CO2-free fuel. However, drawbacks of are—low burning speed and nitrogen oxide emissions. To enhance ammonia's flammability atmospheric micro-combustion, hydrogen is blended First, simplified chemical reaction mechanism consisting 44-step reactions 19 species specifically for developed validated using experimental data to reduce computational cost time. Then, we proposed heat-recirculating micro-combustor fueled by premixed hydrogen/ammonia/air. Five key parameters are identical numerically studying thermal performance, entropy generation, NO The present findings confirm that higher inlet velocity boosts performance (power output achieving 15.8 W at 7 m/s) emissions peak 3 m/s (0.0169). Unity equivalence ratio optimizes rich-fuel combustion reduces At stoichiometric ratio, power 8.34 W, with highest 0.9 (0.168). Hydrogen blending has small effect on (8.5 ξm = 0.7, 0.51 above 0.4), but effectively (ξm 0.7 around 30 % lower than 0.4). Furthermore, changing material from steel Corundum enhances approximately 6 %, while longer heat recirculation improves performance.

Language: Английский

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Overview of the impact of oxygenated biofuel additives on soot emissions in laboratory scale

Fuel Processing Technology, Journal Year: 2024, Volume and Issue: 254, P. 108046 - 108046

Published: Jan. 30, 2024

Soot has harmful effects on the environment and human health. The formation process of soot includes six steps: fuel pyrolysis, nucleation, coalescence, surface growth, aggregation, oxidation. However, is very complex influenced by factors such as type, combustion conditions, environmental temperature. Oxygenated fuels additives have a positive effect reducing emissions, but recent studies shown that oxygenated can lead to an increase in number small particles soot. In this paper, alcohol, ether, esters emissions discussed terms mechanism formation. Subsequently, role after-treatment systems summarized. This work update our understanding impact emissions.

Language: Английский

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Flame visualization and spectral analysis of combustion instability in a premixed methane/air-fueled micro-combustor

Energy, Journal Year: 2024, Volume and Issue: 294, P. 130793 - 130793

Published: Feb. 28, 2024

Language: Английский

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Combustion and emission performance evaluation in ammonia/hydrogen-powered system with baffle and secondary injection applied

Fuel, Journal Year: 2024, Volume and Issue: 367, P. 131457 - 131457

Published: March 19, 2024

Language: Английский

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An Artificial Intelligence-based strategy for multi-objective optimization of combustion and emissions for diesel engine fueled with ammonia-diesel blended fuel with the addition of low-proportion hydrogen

Energy, Journal Year: 2025, Volume and Issue: unknown, P. 134701 - 134701

Published: Jan. 1, 2025

Language: Английский

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Performance Analyses of Telsa-valve Structured Meso-Combustors within Ammonia-Hydrogen/Air Combustion for Thermophotovoltaic Applications

Renewable Energy, Journal Year: 2025, Volume and Issue: 243, P. 122546 - 122546

Published: Jan. 31, 2025

Language: Английский

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Entropy production and thermodynamics exergy investigation on an ammonia-methane fueled micro-combustor with porous medium for thermophotovoltaic applications

International Journal of Hydrogen Energy, Journal Year: 2023, Volume and Issue: 49, P. 384 - 400

Published: Aug. 17, 2023

As conventional fossil fuel is depleting, ammonia has attracted extensive attention as a renewable fuel, which could be made from water, air, and sun. There current interest in burning macro, meso, micro-combustors. The present work concerned with the numerical investigations of entropy production, thermodynamic exergy performance ammonia/methane-fueled micro-combustors single-channel inlet double-channel outlet (SIDO) presence absence porous media (PM). For this, 3D time-domain model developed. With being validated experimental data available literature, it then applied to examine effects 1) equivalence ratio (Φ), 2) velocity (Vin), 3) blending/mixing (Φb) between methane ammonia, 4) PM porosity (σ). In comparison combustion system without PM, application found lead significant improvement on thermal performances, Vin varied. It that there substantial 37.5% reduction standard deviation combustor outer wall temperature ST,W at = 2.0 m/s. optimal achieved, Φ 0.9. However, nitrogen oxide emission shown decreased, increased. production concerned, σ exhibit notable influence. A higher gives rise lower within PM. lowest resulting heat conduction when 0.8. By implementing efficiency (ηexergy) increased by 23.9% general, investigation shed physical insights performances micro-combustion systems

Language: Английский

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Thermal performances and NOx emission studies on an ammonia-hydrogen fueled double-channel outlet micro-combustor for thermophotovoltaic applications

Energy and Built Environment, Journal Year: 2024, Volume and Issue: unknown

Published: Feb. 1, 2024

In this work, we propose and examine an ammonia-hydrogen fueled micro-combustor with a single-channel inlet double-channel outlet (SIDO). The combustion characteristics nitrogen oxide emission of ammonia/hydrogen-oxygen premixed are explored. Comparison is then made between the conventional proposed combustors. It found that our new design could lead to increase outer wall temperature reduce emission. performances different hydrogen blended ratios (Φb), velocities (Vin), equivalence (Φ) evaluated. increasing Φb reduces maximum flame pressure loss, enabling move upstream. When set 25%, convective heat transfer performance reaches its optimal level. uniformity can be improved by Vin. However, it accompanied increased NO emissions at outlet. Increasing Φ significantly emission, such reduction effect much more remarkable lower Φb. Examining exergy efficiency shown greatly in mixed fuel have almost no on ammonia. This study demonstrates feasibility improving thermal reducing varying structure for thermophotovoltaic applications.

Language: Английский

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