Influence of equivalence ratio on turbulent burning velocity and extreme fuel consumption rate in lean hydrogen-air turbulent flames

Lee，Hsu Chew1,2,3; Abdelsamie，Abouelmagd4; Dai，Peng1; Wan，Minping1,2,3; Lipatnikov，Andrei N.5

2022-11-01

10.1016/j.fuel.2022.124969

FUEL   Impact Factor & Quartile

0016-2361

1873-7153

Unsteady three-dimensional Direct Numerical Simulations of seven statistically one-dimensional, planar, highly turbulent, complex-chemistry, lean H-air flames are performed using either mixture averaged or equidiffusive model of molecular transport. The equivalence ratio is varied from 0.35 to 0.70 and the Karlovitz number Ka is varied from 3 to 565. Normalized turbulent burning velocities U/S are strongly increased when using the mixture-averaged model, with an increase by a factor of 4.1 being documented even at Ka as high as 565. Here, S is the laminar flame speed. Moreover, the increase in U/S is significantly more pronounced in leaner flames, which are characterized by a thinner reaction zone and a larger Zel'dovich number. Furthermore, U/S is increased by the turbulence length scale. The extreme (maximum over the computational domain at a single instant) local values of fuel consumption rate (FCR) exhibit a high degree of universality, i.e., in all studied cases and at all instants, these rates are close to the peak values of FCR obtained from the counterpart critically strained, twin, counter-flow laminar premixed flames. This finding appears to directly support a corner-stone hypothesis of the leading point concept of premixed turbulent burning, thus, suggesting the use of characteristics of the critically strained laminar premixed flames as input parameters for models of turbulent combustion of lean H/air mixtures.

Burning velocity Fuel consumption rate Leading point concept Lean hydrogen flames Turbulent combustion

SCI ; EI

English

First ; Corresponding

NSFC["51976088","92041001"] ; Shenzhen Science and Technology Program["KQTD20180411143441009","JCYJ20210324104802005"] ; Department of Science and Technology of Guangdong Province["2019B21203001","2020B1212030001"] ; Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou)[GML2019ZD0103]

Energy & Fuels ; Engineering

Energy & Fuels ; Engineering, Chemical

WOS:000834175400002

ELSEVIER SCI LTD

20222712319103

Air ; Combustion ; Fuels ; Hydrogen ; One dimensional

Chemical Products Generally:804

ENGINEERING

2-s2.0-85133225663

Scopus

1.Guangdong Provincial Key Laboratory of Turbulence Research and Applications,Department of Mechanics and Aerospace Engineering,Southern University of Science and Technology,Shenzhen,518055,China
2.Guangdong-Hong Kong-Macao Joint Laboratory for Data-Driven Fluid Mechanics and Engineering Applications,Southern University of Science and Technology,Shenzhen,518055,China
3.Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou),Guangzhou,511458,China
4.Laboratory of Fluid Dynamics and Technical Flows,University of Magdeburg “Otto Von Guericke”,Magdeburg,39106,Germany
5.Department of Mechanics and Maritime Sciences,Chalmers University of Technology,Gothenburg,SE-412 96,Sweden

Lee，Hsu Chew,Abdelsamie，Abouelmagd,Dai，Peng,et al. Influence of equivalence ratio on turbulent burning velocity and extreme fuel consumption rate in lean hydrogen-air turbulent flames[J]. FUEL,2022,327.

Lee，Hsu Chew,Abdelsamie，Abouelmagd,Dai，Peng,Wan，Minping,&Lipatnikov，Andrei N..(2022).Influence of equivalence ratio on turbulent burning velocity and extreme fuel consumption rate in lean hydrogen-air turbulent flames.FUEL,327.

Lee，Hsu Chew,et al."Influence of equivalence ratio on turbulent burning velocity and extreme fuel consumption rate in lean hydrogen-air turbulent flames".FUEL 327(2022).