{"title":"Laminar flame speeds of supercritical CO2 diluted oxy-syngas and oxy-methane flames under direct-fired power cycle relevant conditions","authors":"Yakun Zhang, Zifeng Weng, Rémy Mével","doi":"10.1016/j.combustflame.2024.113526","DOIUrl":null,"url":null,"abstract":"<div><p>The propagation of laminar oxy-syngas and oxy-methane flames diluted by supercritical carbon dioxide was numerically simulated for the planar flame configuration under the conditions related to the operation of oxy-combustor in the direct-fired power cycle. Because of the extremely high pressure typically used for such an application, real fluid models were considered for the equation of state, thermodynamic functions, transport properties, as well as the mass action law. Numerical results show that the relative uncertainty on the flame speed caused by real gas effects and by different chemical mechanisms can be on the same order of magnitude for oxy-syngas combustion. For oxy-methane combustion, the deviation of the flame speed between the predictions of different mechanisms is much more significant than that caused by real gas effects. The effects of various non-ideal effects were explored progressively. Including the real gas equation of state and thermodynamic functions reduces the adiabatic flame temperature, and thus the flame speed is decreased. Adopting transport properties of real gas and including revisions on the mass action law and equilibrium constant would both increase the flame speed. Inhibition and promotion of flame propagation resulting from the effects of inter-molecular attraction and finite molecular volume were also identified and analyzed.</p><p><strong>Novelty and Significance Statement</strong></p><p>1. Supercritical laminar flame speed was systematically simulated with complete real gas model to quantify the non-ideal effects under direct-fired power cycle relevant conditions.</p><p>2. The individual impact of components in the real gas model on the flame speed were determined and represented with key parameters.</p><p>3. The uncertainties on laminar flame speed caused by reaction mechanism and real gas effects were compared and found to be on the same order of magnitude under certain conditions.</p></div>","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":null,"pages":null},"PeriodicalIF":5.8000,"publicationDate":"2024-05-31","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/S0010218024002359","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}
引用次数: 0
Abstract
The propagation of laminar oxy-syngas and oxy-methane flames diluted by supercritical carbon dioxide was numerically simulated for the planar flame configuration under the conditions related to the operation of oxy-combustor in the direct-fired power cycle. Because of the extremely high pressure typically used for such an application, real fluid models were considered for the equation of state, thermodynamic functions, transport properties, as well as the mass action law. Numerical results show that the relative uncertainty on the flame speed caused by real gas effects and by different chemical mechanisms can be on the same order of magnitude for oxy-syngas combustion. For oxy-methane combustion, the deviation of the flame speed between the predictions of different mechanisms is much more significant than that caused by real gas effects. The effects of various non-ideal effects were explored progressively. Including the real gas equation of state and thermodynamic functions reduces the adiabatic flame temperature, and thus the flame speed is decreased. Adopting transport properties of real gas and including revisions on the mass action law and equilibrium constant would both increase the flame speed. Inhibition and promotion of flame propagation resulting from the effects of inter-molecular attraction and finite molecular volume were also identified and analyzed.
Novelty and Significance Statement
1. Supercritical laminar flame speed was systematically simulated with complete real gas model to quantify the non-ideal effects under direct-fired power cycle relevant conditions.
2. The individual impact of components in the real gas model on the flame speed were determined and represented with key parameters.
3. The uncertainties on laminar flame speed caused by reaction mechanism and real gas effects were compared and found to be on the same order of magnitude under certain conditions.
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.