Thick Exchange Layer Evaporation Model withNatural Convection Effect for MulticomponentDroplet and Its Validation

doi:10.13675/j.cnki. tjjs. 180453

Journal of Propulsion Technology ›› 2019, Vol. 40 ›› Issue (6): 1300-1313.DOI: 10.13675/j.cnki. tjjs. 180453

• Combustion , Heat and Mass Transfer • Previous Articles Next Articles

Thick Exchange Layer Evaporation Model withNatural Convection Effect for MulticomponentDroplet and Its Validation

1.School of Energy and Power Engineering,Beihang University,Beijing 100191,China;2.Collaborative Innovation Center of Advanced Aero-Engine,Beijing 100191,China

Published:2021-08-15

多组分液滴自然对流厚交换层蒸发模型及其检验

刘睿^1,2,李敏^1,2,高翔^1,2,金捷^1,2

1.北京航空航天大学能源与动力工程学院，北京 100191;2.先进航空发动机协同创新中心，北京;100191

基金资助:
国家自然科学基金91741125国家重点研发计划（2017YFB0202400；2017YFB0202402）；国家自然科学基金（91741125）。

Abstract

Abstract: In order to develop the high temperature evaporation model for multicomponent liquid fuel, based on zero-diffusion/infinite diffusion concept, thick exchange layer evaporation model with natural convection effect is expanded to multicomponent liquid fuels and multicomponent NC-TEL model is proposed. Then suspended single droplet evaporation characteristics of three kinds of blended fuel: n-heptane - ethanol, n-decane - ethanol, RP-3 aviation kerosene - ethanol were experimentally studied in high temperature air environment with and without forced convection. The experimental results show that the droplet evaporation rate value increases significantly along with the increase of ambient temperature. And the higher the temperature is, the more significant the composition ratio is to the droplet evaporation rate. The effects of forced convection on droplet evaporation are not very obvious in the condition in this paper. Finally, the model was validated by experimental data. The model comparison results show that on the whole, NC-TEL model behaves better than R-M model, and the prediction accuracy in high temperature test section is improved by 8% to 35% on average. In the lower temperature test section, the zero-diffusion NC-TEL model is in good agreement with the experimental results, while the infinite diffusion NC-TEL model has a certain error. In high temperature test section, for n-heptane - ethanol droplet, the predictions of NC-TEL model are accurate. But for n-decane/RP-3 aviation kerosene- ethanol, the prediction values of NC-TEL model are lower, and possible causes are the microexplosion phenomenon and the Marangoni phenomenon.

Key words: Multicomponent evaporation model;Blended fuel;Suspended droplet experiment;Thick exchange layer model;Natural convection

摘要： 为发展多组分液体燃料高温蒸发模型，首先以零扩散和无限扩散概念为基础，拓展考虑自然对流的厚交换层高温蒸发模型到多组分液体燃料，提出多组分NC-TEL模型。其次，采用挂滴法对正庚烷-乙醇、正癸烷-乙醇、RP-3航空煤油-乙醇三种混合燃料的单液滴在高温静止和强迫对流条件下的蒸发特性进行实验研究。实验结果显示：混合液滴蒸发速率随温度升高而显著增大，温度越高组分构成比例对液滴蒸发率的影响越明显；本文实验条件下，对流环境对于液滴蒸发的促进作用并不明显。最后，用实验数据检验蒸发模型。模型对比结果显示：总体上，NC-TEL模型优于R-M模型，高温段预测精度平均提升了8%~35%；低温段，零扩散NC-TEL模型与实验结果吻合程度较好，而无限扩散NC-TEL模型与实验结果相比误差略大；高温段，对于正庚烷-乙醇混合燃料液滴，NC-TEL模型预测较为准确，而对于正癸烷/RP-3航空煤油-乙醇混合燃料液滴，NC-TEL模型预测值则偏低，可能的原因是微爆现象和Marangoni现象。

关键词: 多组分蒸发模型;混合燃料;挂滴实验;厚交换层模型;自然对流

刘睿,李敏,高翔,金捷. 多组分液滴自然对流厚交换层蒸发模型及其检验[J]. 推进技术, 2019, 40(6): 1300-1313.

References

[1] 王建昕, 闫小光，程勇，等. 乙醇-柴油混合燃料的燃烧与排放特性[J]. 内燃机学报， 2002， 20(3): 225-229.
[2] 刘宇，曾文，马洪安，等. 氢气添加对RP-3航空煤油着火特性的影响[J]. 推进技术， 2016， 37(9):1742-1751.
[3] 赵清华，吴心平. 普通汽油与乙醇汽油的蒸发性分析[J]. 汽车实用技术， 2012，（7）: 83-86.
[4] 王仙菊. 不同比例乙醇汽油蒸发性的测定实验[J]. 化学工程与装备， 2011，（10）: 190-194.
[5] 黄艳仙，莫桂娣，黄克明，等. 乙醇体积分数对乙醇汽油蒸发性能的影响研究[J]. 化学与生物工程， 2009， 26(7): 40-41.
[6] 曾东建，杨建军，姚英. 不同比例乙醇汽油蒸发性实验研究[J]. 小型内燃机与摩托车， 2008，（1）: 71-74.
[7] Godsave A E. Studies of the Combustion of Drops in a Fuel Spray: the Burning of Single Droplets of Fuel[C]. Baltimore M D: Proceedings of the 4th Symposium on Combustion， 1953: 818-830.
[8] Spalding D B. Experiments on the Burning and Extinction of Liquid Fuel Spheres[J]. Fuel， 1953， 3(2): 169–188.
[9] Law C K. Unsteady Droplet Vaporization with Droplet Heating[J]. Combustion and Flame， 1976， 26:17-22.
[10] Law C K， Sirignano W A. Unsteady Droplet Combustion with Droplet Heating II， Conduction Limit[J]. Combustion and Flame， 1977， 29: 175-186.
[11] Prakash S， Sirignano W A. Theory of Convective Droplet Vaporization with Unsteady Heat Transfer in the Circulating Liquid Phase[J]. International Journal of Heat and Mass Transfer， 1980， 23（3）: 253-268.
[12] Prakash S， Sirigano W A. Liquid Fuel Droplet Heating with Internal Circulation[J]. International Journal of Heat and Mass Transfer， 1978， 21（7）: 885-895.
[13] Ranz W E， Marshall W R. Evaporation from Drops—I-II[J]. Chemical Engineering Progress， 1952， 48(141):141-146.
[14] Abramzon B， Sirignano W A. Droplet Vaporization Model for Spray Combustion Calculations[J]. International Journal of Heat and Mass Transfer， 2013， 56(9): 1605-1618.
[15] Bellan J， Harstad K. The Details of the Convective Evaporation of Dense and Dilute Clusters of Drops[J]. International Journal of Heat and Mass Transfer， 1987， 30(6): 1083-1093.
[16] Landis R B， Mills A F. Effect of Internal Diffusional Resistance on the Evaporation of Binary Droplets[M]. Russia: Begel House Inc， 1974.
[17] Da??f A， Bouaziz M， Chesneau X， et al. Comparison of Multicomponent Fuel Droplet Vaporization Experiments in Forced Convection with the Sirignano Model[J]. Experimental Thermal & Fluid Science， 1998， 18(4): 282-290.
[18] Ravindran E P， Davis J. Multicomponent Evaporation of Single Aerosol Droplets[J]. Journal of Colloid & Interface Science， 1982， 85(1): 278-288.
[19] Ghamari M， Ratner A. Combustion Characteristics of Diesel and Jet-A Droplets Blended with Polymeric Additive[J]. Fuel， 2016， 178: 63-70.
[20] Gavhane S， Pati S， Som S K. Evaporation of Multicomponent Liquid Fuel Droplets: Influences of Component Composition in Droplet and Vapor Concentration in Free Stream Ambience[J]. International Journal of Thermal Sciences， 2016， 105: 83-95.
[21] Megaridis C M. Liquid-Phase Variable Property Effects in Multicomponent Droplet Convective Evaporation[J]. Combustion Science & Technology， 1993， 92(4-6): 291-311.
[22] Liu Y C， Avedisian C T. A Comparison of the Spherical Flame Characteristics of Sub-Millimeter Droplets of Binary Mixtures of N-heptane/Iso-octane and N-heptane/Toluene with a Commercial Unleaded Gasoline[J]. Combustion & Flame， 2012， 159(2): 770-783.
[23] Stengele J， Prommersberger K， Willmann M， et al. Experimental and Theoretical Study of One- and Two-component Droplet Vaporization in a High Pressure Environment[J]. International Journal of Heat and Mass Transfer， 1999， 42(14): 2683-2694.
[24] Ghassemi H， Baek S， Khan Q. Experimental Study on Binary Droplet Evaporation at Elevated Pressure and Temperature[C]. Reno: AIAA Aerospace Sciences Meeting and Exhibit， 2005.
[25] Aharon I， Shaw B D. Marangoni Instability of Bi-component Droplet Gasification[J]. Physics of Fluids A， 1996， 8: 1820-1827.
[26] Ha V M ， Lai C L. Onset of Marangoni Instability of a Two-Component Evaporating Droplet[J]. International Journal of Heat & Mass Transfer， 2002， 45(26):5143-58.
[27] 赵鹏. 燃油液滴蒸发过程传热传质机理的数值模拟与实验研究[D]. 北京：北京交通大学， 2012.
[28] Mercier X， Orain M， Grisch F. Experiments on Droplet Combustion in Strained Counterflow Diffusion Flames Using Planar Laser-Induced Fluorescence[J]. Applied Physics B， 2007， 88(1): 151-160.
[29] Wang F， Yao J. A New Stationary Droplet Evaporation Model and Its Validation[J]. Chinese Journal of Aeronautics， 2017， 30(4): 1407-1416.
[30] Wang F， Liu R. Kerosene Evaporation Rate in High Temperature Air Stationary and Convective Environment[J]. Fuel， 2018， 211: 582-590.
[31] Sirignano W. Fluid Dynamics and Transport of Droplets and Sprays[M]. Cambridge: Cambridge University Press， 1999.
[32] Continillo G， Sirignano W A. Unsteady， Spherically-Symmetric Flame Propagation Through Multicomponent Fuel Spray Clouds. Modern Research Topics in Aerospace Propulsion[M]. New York: Springer， 1991:173-198.
[33] Faeth G M. Evaporation and Combustion of Sprays[J]. Progress in Energy & Combustion Science， 1983， 9(1):1-76.
[34] Chen L， Liu Z， Lin Y， et al. Different Spray Droplet Evaporation Models for Non-Ideal Multi-Component Fuels with Experimental Validation[J]. International Journal of Heat and Mass Transfer， 2016， 94(3): 292-300.
[35] 周力行. 燃烧理论和化学流体力学[M]. 北京:科学出版社， 1986： 148-154.
[36] Javed I， Baek S W， Waheed K. Evaporation Characteristics of Heptane Droplets with the Addition of Aluminum Nanoparticles at Elevated Temperatures[J]. Combustion & Flame， 2013， 160(1): 170-183.

Thick Exchange Layer Evaporation Model withNatural Convection Effect for MulticomponentDroplet and Its Validation

多组分液滴自然对流厚交换层蒸发模型及其检验

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