Multiwalled carbon nanotubes (MWCNTs) on a grid supported cobalt nanocatalyst were grown, by exposing it to combustion gases from ethylene/air rich premixed flames. Ten equivalence ratios (φ) were investigated, as follows: 1.37, 1.44, 1.47, 1.50, 1.55, 1.57, 1.62, 1.75, 1.82, and 1.91. MWCNT growth could be observed for the range of equivalence ratios between 1.45 and 1.75, with the best yield ...

Turbulent combustion is a di cult subject as it must deal with all of the issues found in both turbulence and combustion We consider only premixed ames in this paper but some of the ideas can be applied to the non premixed case As in many other elds there are two limiting cases that are easier to deal with than the general case These are the situations in which the chemical time scale is either...

Joint velocity/scalar imaging measurements are performed in turbulent premixed natural-gas/air flames to better characterize the turbulent flux of mean reaction progress variable, ru0c0. Simultaneous two-dimensional measurements of the velocity field and the relative OH concentration are obtained by particle image velocimetry (PIV) and planar laser-induced fluorescence (PLIF) of the OH radical,...

For industrial applications, we propose a concept of clean and efficient combustion through burning syngas on an impinging burner. We performed experimental measurements of particle image velocimetry, OH radical (OH*) chemiluminescence, flame temperature, and CO emission to examine the fuel mixing and reaction of premixed impinging flames of CH4/syngas/air with H2/CO in varied proportions. The ...

Parallel simulation of unsteady turbulent combustion is carried out for a range of precursor test problems leading to the development of a new methodology for reacting two-phase flows. Simulations are carried out using large-eddy simulations (LES) which allows full spatio-temporal resolution of all scales larger than the grid resolution with the unresolved small-scales modeled by a localized dy...

0010-2180/$ see front matter 2010 The Combust doi:10.1016/j.combustflame.2010.02.018 * Corresponding author. Address: University of Illin Mechanical & Industrial Engineering, 842 West Tayl 7022, USA. Fax: +1 312 413 0441. E-mail address: [email protected] (S.K. Aggarwal). Injector flow dynamics and primary breakup processes are known to play a pivotal role in determining combustion and emissions in d...

A non-premixed coaxial oxy-fuel turbulent flame was studied numerically with standard and realizable k-ε turbulence model and a comparison was made between them. The governing equations were solved by finite volume approach and were discretized using the second order upwind scheme. The presumed β-PDF model was applied to model turbulence-combustion interaction. The discrete ordinate radiation h...

The flame front filtering is a well-known strategy in turbulent premixed combustion. An extension of this approach for the non-premixed combustion context has been proposed by means directly counterflow diffusion flamelets. Promising results were obtained filtered tabulated chemistry formalism on 1-D and 2-D unresolved configurations. present paper demonstrates soundness 3-D real laminar coflow...

Computational simulation of turbulent combustion has the potential to play a very important role in fundamental research and in the design of combustion devices, yet it remains problematic for many practical applications. Although it is certainly possible to perform fully resolved direct numerical simulations (DNS) with detailed chemistry and transport on idealized centimeter-scale domains, eve...