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Thermodiffusive instabilities can have a leading order effect on flame propagation for lean premixed hydrogen flames. Many simulation studies have been performed to study this effect, but almost exclusively in two-dimensional (2D) or domain…

Fluid Dynamics · Physics 2023-12-20 Wen Xu , Berger Lukas , Cai Liming , Parente Alessandro , Pitsch Heinz

Propagation of weakly stretched spherical flames in partially pre-vaporized fuel sprays is theoretically investigated in this work. A general theory is developed to describe flame propagation speed, flame temperature, droplet evaporation…

Fluid Dynamics · Physics 2021-02-03 Qiang Li , Huangwei Zhang , Chang Shu

The combined influence of elevated pressure and temperature, representative of gas-turbine operating conditions, on lean premixed hydrogen flames is investigated using Direct Numerical Simulations (DNS) of a turbulent jet. Three cases are…

Three-dimensional numerical simulations of canonical statistically-steady statistically-planar turbulent flames have been used in an attempt to produce distributed burning in lean methane and hydrogen flames. Dilatation across the flame…

Fluid Dynamics · Physics 2019-05-22 A. J. Aspden , M. S. Day , J. B. Bell

Starting with an integral formulation of mass flow rate through an ensemble of isotherms constituting a statistically planar, turbulent premixed flame, a scaling for the corresponding turbulent flame speed is derived without invoking…

Fluid Dynamics · Physics 2022-07-14 Swetaprovo Chaudhuri , Bruno Savard

The effect of swirl, premixedness and geometry has been investigated for hydrogen enriched premixed flame using Large Eddy Simulation (LES) with a Thickened Flame (TF) model. Swirl strength has been varied to study the effects of swirl on…

Fluid Dynamics · Physics 2021-02-11 Ashoke De , Sumanta Acharya

This paper provides an extension of the standard flamelet progress variable (FPV) approach for turbulent combustion, applying the statistically most likely distribution (SMLD) framework to the joint PDF of the mixture fraction, Z, and the…

Fluid Dynamics · Physics 2013-06-21 Alessandro Coclite , Giuseppe Pascazio , Pietro De Palma , Luigi Cutrone

This study presents a comprehensive a priori analysis of tabulated-chemistry models for both laminar and turbulent lean premixed hydrogen flames in strained counterflow configuration. Particular focus is drawn on differential and…

Lean premixed hydrogen-air flames are strongly affected by thermodiffusive (TD) instabilities, which can alter the flame structure and enhance the local reactivity many-fold. Two recent models (Howarth et al. (Combust.~Flame 253, 2023) and…

The structure of a laminar rich premixed 1,3-C4H6/CH4/O2/Ar flame have been investigated. 1,3-Butadiene, methane, oxygen and argon mole fractions are 0.033; 0.2073; 0.3315, and 0.4280, respectively, for an equivalent ratio of 1.80. The…

This study presents a numerical analysis of the impact of hydrogen addition on the consumption speed of premixed lean methane-air laminar flames exposed to combined strain and heat loss. Equivalence ratios of 0.9, 0.7, and 0.5 with fuel…

Fluid Dynamics · Physics 2023-07-19 Alex M. Garcia , Sophie Le Bras , Wolfgang Polifke

First-principles Markov Chain Monte Carlo sampling is used to investigate uncertainty quantification and uncertainty propagation in parameters describing hydrogen kinetics. Specifically, we sample the posterior distribution of thirty-one…

Numerical Analysis · Mathematics 2018-03-12 John Bell , Marcus Day , Jonathan Goodman , Ray Grout , Matthias Morzfeld

The influence of equivalence ratio on preferential diffusion effects and the resulting changes in the distributions of major species and their reaction rates have been analysed based on 2D simulations of lean ${\mathrm{H_2}}$-air laminar…

Fluid Dynamics · Physics 2024-05-21 Frederick W Young , Umair Ahmed , Nilanjan Chakraborty

Turbulent premixed flames are important for power generation using gas turbines. Improvements in characterization and understanding of turbulent flames continue particularly for transient events like ignition and extinction. Pockets or…

Computer Vision and Pattern Recognition · Computer Science 2020-12-04 Rathziel Roncancio , Jupyoung Kim , Aly El Gamal , Jay P. Gore

Most studies of triple flames in counterflowing streams of fuel and oxidizer have been focused on the symmetric problem in which the stoichiometric mixture fraction is $1/2$. There then exist lean and rich premixed flames of roughly equal…

Diffusive transport of mass occurs at small scales in turbulent premixed flames. As a result, multicomponent mass diffusion, which is often neglected in direct numerical simulations (DNS) of premixed combustion, has the potential to impact…

Fluid Dynamics · Physics 2022-07-20 Aaron J. Fillo , Peter E. Hamlington , Kyle E. Niemeyer

Influences of reaction zone thickening and local extinctions on the burning rate of extremely turbulent hydrogen-enriched methane-air flames are investigated using simultaneous planar laser-induced fluorescence of formaldehyde molecule and…

Fluid Dynamics · Physics 2020-12-01 Sajjad Mohammadnejad , Qiang An , Patrizio Vena , Sean Yun , Sina Kheirkhah

In order to better understand the chemistry involved during the combustion of components of diesel fuel, the structure of a laminar lean premixed methane flame doped with indane has been investigated. The gases of this flame contains 7.1%…

Chemical Physics · Physics 2009-03-26 Emir Pousse , Pierre-Alexandre Glaude , René Fournet , Frédérique Battin-Leclerc

Liquid ammonia combustion can be enhanced by co-firing with small molecular fuels such as methane, and liquid ammonia will undergo flash evaporation due to its relatively low saturation pressure. These characteristics, involving the…

Fluid Dynamics · Physics 2024-09-23 Zhenhua An , Jiangkuan Xing , Abhishek Lakshman Pillai , Ryoichi Kurose

Implementing multicomponent diffusion models in numerical combustion studies is computationally expensive; to reduce cost, numerical simulations commonly use mixture-averaged diffusion treatments or simpler models. However, the accuracy and…

Fluid Dynamics · Physics 2020-10-19 Aaron J. Fillo , Jason Schlup , Guillaume Blanquart , Kyle E. Niemeyer