Effects of finite-rate droplet evaporation on the extinction of   spherical burner-stabilized diffusion flames

doi:10.1016/j.ijheatmasstransfer.2016.04.003

CORC > 北京大学 > 工学院

	Effects of finite-rate droplet evaporation on the extinction of spherical burner-stabilized diffusion flames
	Han, Wang ; Chen, Zheng
刊名	INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
	2016
关键词	Droplet evaporation Radiation Lewis number Spray diffusion flame Extinction NONUNITY LEWIS NUMBERS POLYDISPERSE WATER SPRAY OPPOSED-FLOW ASYMPTOTIC THEORY RADIATIVE EXTINCTION SECTIONAL APPROACH PREMIXED FLAMES BOUNDARY-LAYER STEADY-STATE SHEAR-LAYER
DOI	10.1016/j.ijheatmasstransfer.2016.04.003
英文摘要	Multistate asymptotic analysis is conducted for spherical burner-stabilized spray diffusion flames with finite-rate droplet evaporation and nonunity Lewis number. The radiative heat loss is considered and the effects of radiation on flame extinction are examined. The structure function of the spray diffusion flame is derived, based on which the effects of finite-rate droplet evaporation on flame radius, flame temperature, and kinetic and radiative extinction limits are assessed. The flame is found to be affected by droplet evaporation in two ways: (1) the latent heat absorbed for droplet evaporation reduces the flame temperature; and (2) the decrease in the flame radius results in the decrease in radiative loss and residence time. For a given the mass flow rate, only the conventional kinetic extinction limit at low reaction Damkohler number exists. The extinction Damkohler number increases with the radiation intensity and it is significantly affected by droplet evaporation. It is found that at higher radiation intensity, the spray flame with the lower vaporization Damkohler number is relatively more difficult to be extinguished than the purely gaseous flame. When the reaction intensity is fixed and the mass flow rate varies, there exists two extinction limits: a kinetic extinction limit at a low-flow rate and a radiative extinction limit at a high-flow rate. Steady burning only exists between these two extinction limits. The flammable zone is shown to be greatly affected by droplet evaporation and is very sensitive to Lewis number. (C) 2016 Elsevier Ltd. All rights reserved.; National Natural Science Foundation of China [51322602, 51136005]; SCI(E); EI; ARTICLE; cz@pku.edu.cn; 691-701; 99
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/437076]
专题	工学院
推荐引用方式 GB/T 7714	Han, Wang,Chen, Zheng. Effects of finite-rate droplet evaporation on the extinction of spherical burner-stabilized diffusion flames[J]. INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER,2016.
APA	Han, Wang,&Chen, Zheng.(2016).Effects of finite-rate droplet evaporation on the extinction of spherical burner-stabilized diffusion flames.INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER.
MLA	Han, Wang,et al."Effects of finite-rate droplet evaporation on the extinction of spherical burner-stabilized diffusion flames".INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER (2016).