{"title":"加氢对高温崖体稳定贫预混火焰结构的影响","authors":"Siqi Cai, Jianlong Wan","doi":"10.1016/j.combustflame.2025.114229","DOIUrl":null,"url":null,"abstract":"<div><div>It has been confirmed that the High-temperature bluff-body (HTB) can significantly improve the Lean premixed flame (LPF) stabilization. To further improve the HTB stabilized LPF performance and reduce the CO<sub>2</sub> emission, the hydrogen-methane is employed. This study investigates the hydrogen addition effect on the LPF structure stabilized on the HTB by the means of the numerical simulation. A new non-equidistant central difference method is employed to identify the normal vector of the flame front accurately. When the percentage <em>α</em> of hydrogen in the mixed fuel increases, the flame thickness significantly decreases and its base shifts upstream. In the case of <em>α</em>=0, the flame base immerses in the Recirculation zone (RZ), and the flame base anchors at the boundary of the RZ in the case of <em>α</em>=0.15 and 0.30. The transport path and magnitude of the reactants are visualized. It is interestingly observed that the hydrogen addition can promote the transport magnitude of methane to the flame. When <em>α</em> increases, the peak values of the net reaction rates of hydrogen and methane increase, and the corresponding locations shift upstream. The three source terms of the energy equation are visualized quantitatively employing the real specific heat rather than the conventional constant equivalent specific heat. The increase in the <em>α</em> value enlarges the magnitudes of the aforementioned three source terms significantly. For the downstream flame front, it is interestingly observed that the weight of the convection term is large in the case of <em>α</em>=0 while it is small in the case of <em>α</em>=0.30. The heat release rate structure can be classified into the adiabatic zone, the excess reaction zone, and the weak reaction zone. To the best of our knowledge, such detailed analysis of the HTB stabilized LPF structure of hydrogen-enriched methane has not been reported yet. This work offers new insights into the LPF dynamics stabilized on the HTB.</div></div>","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":"277 ","pages":"Article 114229"},"PeriodicalIF":5.8000,"publicationDate":"2025-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Hydrogen addition effect on the structure of the lean premixed flame stabilized on a high-temperature bluff-body\",\"authors\":\"Siqi Cai, Jianlong Wan\",\"doi\":\"10.1016/j.combustflame.2025.114229\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>It has been confirmed that the High-temperature bluff-body (HTB) can significantly improve the Lean premixed flame (LPF) stabilization. To further improve the HTB stabilized LPF performance and reduce the CO<sub>2</sub> emission, the hydrogen-methane is employed. This study investigates the hydrogen addition effect on the LPF structure stabilized on the HTB by the means of the numerical simulation. A new non-equidistant central difference method is employed to identify the normal vector of the flame front accurately. When the percentage <em>α</em> of hydrogen in the mixed fuel increases, the flame thickness significantly decreases and its base shifts upstream. In the case of <em>α</em>=0, the flame base immerses in the Recirculation zone (RZ), and the flame base anchors at the boundary of the RZ in the case of <em>α</em>=0.15 and 0.30. The transport path and magnitude of the reactants are visualized. It is interestingly observed that the hydrogen addition can promote the transport magnitude of methane to the flame. When <em>α</em> increases, the peak values of the net reaction rates of hydrogen and methane increase, and the corresponding locations shift upstream. The three source terms of the energy equation are visualized quantitatively employing the real specific heat rather than the conventional constant equivalent specific heat. The increase in the <em>α</em> value enlarges the magnitudes of the aforementioned three source terms significantly. For the downstream flame front, it is interestingly observed that the weight of the convection term is large in the case of <em>α</em>=0 while it is small in the case of <em>α</em>=0.30. The heat release rate structure can be classified into the adiabatic zone, the excess reaction zone, and the weak reaction zone. To the best of our knowledge, such detailed analysis of the HTB stabilized LPF structure of hydrogen-enriched methane has not been reported yet. This work offers new insights into the LPF dynamics stabilized on the HTB.</div></div>\",\"PeriodicalId\":280,\"journal\":{\"name\":\"Combustion and Flame\",\"volume\":\"277 \",\"pages\":\"Article 114229\"},\"PeriodicalIF\":5.8000,\"publicationDate\":\"2025-05-10\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Combustion and Flame\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0010218025002676\",\"RegionNum\":2,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"ENERGY & FUELS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Combustion and Flame","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0010218025002676","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENERGY & FUELS","Score":null,"Total":0}
Hydrogen addition effect on the structure of the lean premixed flame stabilized on a high-temperature bluff-body
It has been confirmed that the High-temperature bluff-body (HTB) can significantly improve the Lean premixed flame (LPF) stabilization. To further improve the HTB stabilized LPF performance and reduce the CO2 emission, the hydrogen-methane is employed. This study investigates the hydrogen addition effect on the LPF structure stabilized on the HTB by the means of the numerical simulation. A new non-equidistant central difference method is employed to identify the normal vector of the flame front accurately. When the percentage α of hydrogen in the mixed fuel increases, the flame thickness significantly decreases and its base shifts upstream. In the case of α=0, the flame base immerses in the Recirculation zone (RZ), and the flame base anchors at the boundary of the RZ in the case of α=0.15 and 0.30. The transport path and magnitude of the reactants are visualized. It is interestingly observed that the hydrogen addition can promote the transport magnitude of methane to the flame. When α increases, the peak values of the net reaction rates of hydrogen and methane increase, and the corresponding locations shift upstream. The three source terms of the energy equation are visualized quantitatively employing the real specific heat rather than the conventional constant equivalent specific heat. The increase in the α value enlarges the magnitudes of the aforementioned three source terms significantly. For the downstream flame front, it is interestingly observed that the weight of the convection term is large in the case of α=0 while it is small in the case of α=0.30. The heat release rate structure can be classified into the adiabatic zone, the excess reaction zone, and the weak reaction zone. To the best of our knowledge, such detailed analysis of the HTB stabilized LPF structure of hydrogen-enriched methane has not been reported yet. This work offers new insights into the LPF dynamics stabilized on the HTB.
期刊介绍:
The mission of the journal is to publish high quality work from experimental, theoretical, and computational investigations on the fundamentals of combustion phenomena and closely allied matters. While submissions in all pertinent areas are welcomed, past and recent focus of the journal has been on:
Development and validation of reaction kinetics, reduction of reaction mechanisms and modeling of combustion systems, including:
Conventional, alternative and surrogate fuels;
Pollutants;
Particulate and aerosol formation and abatement;
Heterogeneous processes.
Experimental, theoretical, and computational studies of laminar and turbulent combustion phenomena, including:
Premixed and non-premixed flames;
Ignition and extinction phenomena;
Flame propagation;
Flame structure;
Instabilities and swirl;
Flame spread;
Multi-phase reactants.
Advances in diagnostic and computational methods in combustion, including:
Measurement and simulation of scalar and vector properties;
Novel techniques;
State-of-the art applications.
Fundamental investigations of combustion technologies and systems, including:
Internal combustion engines;
Gas turbines;
Small- and large-scale stationary combustion and power generation;
Catalytic combustion;
Combustion synthesis;
Combustion under extreme conditions;
New concepts.