English
Related papers

Related papers: An analytic probability density function for parti…

200 papers

In this paper we investigate the acceleration of the expansion of premixed spherical flames and evolution of the cellular patterns on their surfaces. An asymptotic model is used for the simulations and a spectral numerical algorithm is…

Fluid Dynamics · Physics 2017-02-01 V. Karlin , G. Sivashinsky

Localized wrinkles of thin premixed flames subject to hydrodynamic instability and geometrical stretch of uniform intensity (S) are studied. A stretch-affected nonlinear and nonlocal equation, derived from an inhomogeneous…

Fluid Dynamics · Physics 2011-09-14 Bruno Denet , Guy Joulin

The present paper reports on the numerical investigation of lifted turbulent jet flames with H2/N2 fuel issuing into a vitiated coflow of lean combustion products of H2/air using conditional moment closure method (CMC). A 2D axisymmetric…

Fluid Dynamics · Physics 2021-02-10 Santanu De , Ashoke De , Abhishek Jaiswal , Arpita Dash

The stabilization mechanisms of fully premixed NH3/H2/air flames anchored behind a bluff body are investigated using combined experiments and direct numerical simulations. Particular attention is given to the interplay between preferential…

Fluid Dynamics · Physics 2026-03-10 Lukas Gaipl , Wei Guan , Ganesh Guggilla , Alexey Kropman , Frank Beyrau , Dominique Thévenin

Comprehensive knowledge of local flame displacement speed, $S_d$, in turbulent premixed flames is crucial towards the design and development of hydrogen fuelled next-generation engines. Premixed hydrogen-air flames are characterized by…

Fluid Dynamics · Physics 2021-11-03 Yuvraj , Wonsik Song , Himanshu Dave , Hong G. Im , Swetaprovo Chaudhuri

Turbulent mixing is a physical process of fundamental importance in high-speed premixed flames. This mixing results in enhanced transport of temperature and chemical scalars, leading to potentially large changes in flame structure and…

Fluid Dynamics · Physics 2020-06-25 Ryan Darragh , Colin A. Z. Towery , Alexei Y. Poludnenko , Peter E. Hamlington

Performing alchemical transformations, in which one molecular system is nonphysically changed to another system, is a popular approach adopted in performing free energy calculations associated with various biophysical processes, such as…

Statistical Mechanics · Physics 2023-12-15 Wei-Tse Hsu , Valerio Piomponi , Pascal T. Merz , Giovanni Bussi , Michael R. Shirts

Gibson scaling and related properties of flame-surface geometry in turbulent premixed combustion are demonstrated using a novel computational model, Deterministic Turbulent Mixing (DTM). In DTM, turbulent advection is represented by a…

Astrophysics · Physics 2007-05-23 J. C. Niemeyer , A. R. Kerstein

Combustion stabilization and enhancement of the flammability limits are mandatory objectives to improve nowadays combustion chambers. At this purpose, the use of an electric field in the flame region provides a solution which is, at the…

Fluid Dynamics · Physics 2017-12-13 M. Di Renzo , P. De Palma , M. D. de Tullio , G. Pascazio

In this paper, we consider a reaction-diffusion system describing the propagation of flames under the assumption of ignition-temperature kinetics and fractional reaction order. It was shown in [3] that this system admits a traveling front…

Analysis of PDEs · Mathematics 2024-02-29 Amanda Matson , Claude-Michel Brauner , Peter V. Gordon

The nonlinear nonlocal Michelson-Sivashinsky equation for isolated crests of unstable flames is studied, using pole-decompositions as starting point. Polynomials encoding the numerically computed 2N flame-slope poles, and auxiliary ones,…

Pattern Formation and Solitons · Physics 2015-06-23 Bruno Denet , Guy Joulin

In the distributed burning regime, turbulence disrupts the internal structure of the flame, and so the idea of laminar burning propagated by conduction is no longer valid. The nature of the burning depends on the turbulent Damkohler number…

High Energy Astrophysical Phenomena · Physics 2011-07-14 A J Aspden , J B Bell , S E Woosley

In this paper we present results of direct numerical simulations of lean hydrogen/air flames freely propagating in a planar narrow channel with varying flow rate, using detailed chemistry and transport and including heat losses through the…

Fluid Dynamics · Physics 2018-02-16 Carmen Jimenez , Vadim N. Kurdyumov

Two-dimensional direct numerical simulations of planar laminar premixed ammonia/hydrogen/air flames are conducted for a wide range of equivalence ratios, hydrogen ($\rm H_2$) fractions in the fuel blend, pressures, and unburned temperatures…

Our recent development of a novel research burner has made it possible to experimentally investigate truly unstretched and planar diffusion flames. Hence it has become feasible to directly validate theoretical models for thermal-diffusive…

Fluid Dynamics · Physics 2025-04-09 Etienne Robert , Peter A. Monkewitz

This study investigated the pulsating instability of burner-stabilized premixed CH4-O2 flames at various levels of CO2 dilution. Experiments were conducted using a water-cooled porous-plug burner of 18 mm diameter over a wide range of…

Fluid Dynamics · Physics 2026-01-23 Xiangyu Nie , Shuoxun Zhang , Shengkai Wang

Aspects of predictions of activation-energy asymptotics concerning the dependence of the burning velocity on the equivalence ratio are examined here through both asymptotic analyses and numerical computation. In typical hydrocarbon-air…

Fluid Dynamics · Physics 2024-06-28 Prabakaran Rajamanickam

The critical dimension necessary for a flame to propagate in suspensions of fuel particles in oxidizer is studied analytically and numerically. Two types of models are considered: First, a continuum model, wherein the individual particulate…

Fluid Dynamics · Physics 2019-12-23 Fredric Y. K. Lam , XiaoCheng Mi , Andrew J. Higgins

Lean turbulent premixed hydrogen/air flames have substantially increased flame speeds, commonly attributed to differential diffusion effects. In this work, the effect of turbulence on lean hydrogen combustion is studied through Direct…

Fluid Dynamics · Physics 2024-08-20 Matthew X. Yao , Guillaume Blanquart

Nonlinear non-stationary equation describing evolution of weakly curved premixed flames with arbitrary gas expansion, subject to the Landau-Darrieus instability, is derived. The new equation respects all the conservation laws to be…

Fluid Dynamics · Physics 2007-05-23 Kirill A. Kazakov , Michael A. Liberman