Linyuan Huang , Chonghua Lai , Sheng Huang , Yang Zuo , Quan Zhu
{"title":"C10 碳氢化合物/空气膨胀火焰的湍流火焰传播:基于马克斯坦数的可能统一相关性","authors":"Linyuan Huang , Chonghua Lai , Sheng Huang , Yang Zuo , Quan Zhu","doi":"10.1016/j.combustflame.2024.113724","DOIUrl":null,"url":null,"abstract":"<div><p>In this study, we experimentally analyzed the influence of turbulence and thermal-diffusional effect on the morphology and turbulent flame speed of premixed expanding flames. The turbulent flames of the n-decane/air and decalin/air mixtures were measured using a fan-stirred constant volume combustion bomb generating near-isotropic turbulence at elevated pressures (1, 2, and 5 bar), temperature (443 K), and a wide range of equivalence ratios (0.8–1.6). The results found that the wrinkling degree of the flame front was greater for <span><math><mrow><mi>M</mi><mi>a</mi></mrow></math></span><0 compared to <span><math><mrow><mi>M</mi><mi>a</mi></mrow></math></span>>0. However, the distribution patterns of the curvature radius of the flame contours exhibited similarities across different equivalence ratios. Furthermore, an increase in turbulence intensity would aggravate the randomness of flame contour distribution. The turbulent expanding flames of n-decane/air and decalin/air mixtures were self-similar under different turbulence intensities and pressures, and this self-similar propagation followed a correlation between the normalized turbulent flame speed and the turbulent flame Reynolds number (<span><math><mrow><mi>R</mi><msub><mi>e</mi><mrow><mi>T</mi><mo>,</mo><mi>f</mi></mrow></msub></mrow></math></span>) to the one-half power. The similarity in normalized turbulent flame speeds was extended from normal alkanes (C4-C8) and isomeric alkanes (C8, C16) to longer straight-chain alkane (n-decane) and cycloalkane (decalin). As the increase of equivalence ratio, their normalized turbulent flame speeds increased nonlinearly due to the thermal-diffusional effect. Additionally, it was found that the classical, effective, and experimental Lewis numbers were confirmed as unsuitable parameters for characterizing the role of thermal-diffusional effect on the turbulent flame speed for hydrocarbon fuels with large molecular weight. Finally, two possible unified correlations were proposed based on the Markstein number, <span><math><mrow><mrow><mo>(</mo><mrow><mi>d</mi><mo>〈</mo><mi>r</mi><mo>〉</mo><mo>/</mo><mi>d</mi><mi>t</mi></mrow><mo>)</mo></mrow><mo>/</mo><mrow><mo>(</mo><mrow><mi>σ</mi><msub><mi>S</mi><mi>L</mi></msub></mrow><mo>)</mo></mrow><mo>=</mo><mn>0.178</mn><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo><mn>0.231</mn><mi>M</mi><mi>a</mi></mrow></msup><mi>R</mi><msubsup><mi>e</mi><mrow><mi>T</mi><mo>,</mo><mi>f</mi></mrow><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msubsup></mrow></math></span> and <span><math><mrow><mrow><mo>(</mo><mrow><mi>d</mi><mo>〈</mo><mi>r</mi><mo>〉</mo><mo>/</mo><mi>d</mi><mi>t</mi></mrow><mo>)</mo></mrow><mo>/</mo><mrow><mo>(</mo><mrow><mi>σ</mi><msub><mi>S</mi><mi>L</mi></msub></mrow><mo>)</mo></mrow><mo>=</mo><mrow><mo>(</mo><mrow><mn>0.170</mn><mo>−</mo><mn>0.0447</mn><mi>M</mi><mi>a</mi><mo>+</mo><mn>0.0067</mn><mi>M</mi><msup><mrow><mi>a</mi></mrow><mn>2</mn></msup></mrow><mo>)</mo></mrow><mi>R</mi><msubsup><mi>e</mi><mrow><mi>T</mi><mo>,</mo><mi>f</mi></mrow><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msubsup></mrow></math></span>, which could predict the turbulent flame speeds of hydrocarbon fuels with large molecular weight such as n-alkanes, iso-alkanes, and decalin.</p></div>","PeriodicalId":280,"journal":{"name":"Combustion and Flame","volume":"270 ","pages":"Article 113724"},"PeriodicalIF":5.8000,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Turbulent flame propagation of C10 hydrocarbons/air expanding flames: Possible unified correlation based on the Markstein number\",\"authors\":\"Linyuan Huang , Chonghua Lai , Sheng Huang , Yang Zuo , Quan Zhu\",\"doi\":\"10.1016/j.combustflame.2024.113724\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>In this study, we experimentally analyzed the influence of turbulence and thermal-diffusional effect on the morphology and turbulent flame speed of premixed expanding flames. The turbulent flames of the n-decane/air and decalin/air mixtures were measured using a fan-stirred constant volume combustion bomb generating near-isotropic turbulence at elevated pressures (1, 2, and 5 bar), temperature (443 K), and a wide range of equivalence ratios (0.8–1.6). The results found that the wrinkling degree of the flame front was greater for <span><math><mrow><mi>M</mi><mi>a</mi></mrow></math></span><0 compared to <span><math><mrow><mi>M</mi><mi>a</mi></mrow></math></span>>0. However, the distribution patterns of the curvature radius of the flame contours exhibited similarities across different equivalence ratios. Furthermore, an increase in turbulence intensity would aggravate the randomness of flame contour distribution. The turbulent expanding flames of n-decane/air and decalin/air mixtures were self-similar under different turbulence intensities and pressures, and this self-similar propagation followed a correlation between the normalized turbulent flame speed and the turbulent flame Reynolds number (<span><math><mrow><mi>R</mi><msub><mi>e</mi><mrow><mi>T</mi><mo>,</mo><mi>f</mi></mrow></msub></mrow></math></span>) to the one-half power. The similarity in normalized turbulent flame speeds was extended from normal alkanes (C4-C8) and isomeric alkanes (C8, C16) to longer straight-chain alkane (n-decane) and cycloalkane (decalin). As the increase of equivalence ratio, their normalized turbulent flame speeds increased nonlinearly due to the thermal-diffusional effect. Additionally, it was found that the classical, effective, and experimental Lewis numbers were confirmed as unsuitable parameters for characterizing the role of thermal-diffusional effect on the turbulent flame speed for hydrocarbon fuels with large molecular weight. Finally, two possible unified correlations were proposed based on the Markstein number, <span><math><mrow><mrow><mo>(</mo><mrow><mi>d</mi><mo>〈</mo><mi>r</mi><mo>〉</mo><mo>/</mo><mi>d</mi><mi>t</mi></mrow><mo>)</mo></mrow><mo>/</mo><mrow><mo>(</mo><mrow><mi>σ</mi><msub><mi>S</mi><mi>L</mi></msub></mrow><mo>)</mo></mrow><mo>=</mo><mn>0.178</mn><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo><mn>0.231</mn><mi>M</mi><mi>a</mi></mrow></msup><mi>R</mi><msubsup><mi>e</mi><mrow><mi>T</mi><mo>,</mo><mi>f</mi></mrow><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msubsup></mrow></math></span> and <span><math><mrow><mrow><mo>(</mo><mrow><mi>d</mi><mo>〈</mo><mi>r</mi><mo>〉</mo><mo>/</mo><mi>d</mi><mi>t</mi></mrow><mo>)</mo></mrow><mo>/</mo><mrow><mo>(</mo><mrow><mi>σ</mi><msub><mi>S</mi><mi>L</mi></msub></mrow><mo>)</mo></mrow><mo>=</mo><mrow><mo>(</mo><mrow><mn>0.170</mn><mo>−</mo><mn>0.0447</mn><mi>M</mi><mi>a</mi><mo>+</mo><mn>0.0067</mn><mi>M</mi><msup><mrow><mi>a</mi></mrow><mn>2</mn></msup></mrow><mo>)</mo></mrow><mi>R</mi><msubsup><mi>e</mi><mrow><mi>T</mi><mo>,</mo><mi>f</mi></mrow><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msubsup></mrow></math></span>, which could predict the turbulent flame speeds of hydrocarbon fuels with large molecular weight such as n-alkanes, iso-alkanes, and decalin.</p></div>\",\"PeriodicalId\":280,\"journal\":{\"name\":\"Combustion and Flame\",\"volume\":\"270 \",\"pages\":\"Article 113724\"},\"PeriodicalIF\":5.8000,\"publicationDate\":\"2024-09-14\",\"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/S0010218024004334\",\"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/S0010218024004334","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}
Turbulent flame propagation of C10 hydrocarbons/air expanding flames: Possible unified correlation based on the Markstein number
In this study, we experimentally analyzed the influence of turbulence and thermal-diffusional effect on the morphology and turbulent flame speed of premixed expanding flames. The turbulent flames of the n-decane/air and decalin/air mixtures were measured using a fan-stirred constant volume combustion bomb generating near-isotropic turbulence at elevated pressures (1, 2, and 5 bar), temperature (443 K), and a wide range of equivalence ratios (0.8–1.6). The results found that the wrinkling degree of the flame front was greater for <0 compared to >0. However, the distribution patterns of the curvature radius of the flame contours exhibited similarities across different equivalence ratios. Furthermore, an increase in turbulence intensity would aggravate the randomness of flame contour distribution. The turbulent expanding flames of n-decane/air and decalin/air mixtures were self-similar under different turbulence intensities and pressures, and this self-similar propagation followed a correlation between the normalized turbulent flame speed and the turbulent flame Reynolds number () to the one-half power. The similarity in normalized turbulent flame speeds was extended from normal alkanes (C4-C8) and isomeric alkanes (C8, C16) to longer straight-chain alkane (n-decane) and cycloalkane (decalin). As the increase of equivalence ratio, their normalized turbulent flame speeds increased nonlinearly due to the thermal-diffusional effect. Additionally, it was found that the classical, effective, and experimental Lewis numbers were confirmed as unsuitable parameters for characterizing the role of thermal-diffusional effect on the turbulent flame speed for hydrocarbon fuels with large molecular weight. Finally, two possible unified correlations were proposed based on the Markstein number, and , which could predict the turbulent flame speeds of hydrocarbon fuels with large molecular weight such as n-alkanes, iso-alkanes, and decalin.
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.