Showing papers in "Combustion and Flame in 1988"

TL;DR: In this paper, global reaction schemes for the combustion of alkane hydrocarbons up to butane in mixtures with air in premixed and diffusion flames have been derived using analysis of flame structures.

TL;DR: In this article, a detailed reaction mechanism and a multispecies transport model were used to simulate the explosion limits of the hydrogen-oxygen system and the minimum ignition energies for various mixture compositions, pressures, radii of the external energy source and ignition times.

TL;DR: In this paper, the asymptotic structure of a counterflow methane-air diffusion flame is analyzed using a three-step chemical kinetic mechanism, which was deduced in a systematic way through steady state and partial equilibrium assumptions from a detailed chemical kinetic model for oxidation of methane.

TL;DR: In this paper, the structure and propagation of stretched premixed flames with preferential diffusion are analyzed using an approximate integral approach which yields algebraic relations for the characteristic scales, overall conservation requirements, and balances and continuity between the various scalar properties and their transport rates.

TL;DR: In this paper, the authors used a quartz sampling probe to measure the concentration profiles of the single-ring aromatics benzene, phenylacetylene, and styrene in heavily sooting premixed ethylene flames.

TL;DR: In this article, the authors measured temperature distributions within the PMMA sample in the vicinity of the leading edge of the flame front using holographic interferometry and found that the heat flow vector patterns within the sample showed the dominant heat transfer path from the gas phase into the unburnt fuel ahead of the vaporization point.

TL;DR: In this article, the effects of strain on the structure of premixed laminar flames are investigated numerically for various counterflow configurations that can develop in turbulent flow, and the results are based on both a mechanism of elementary reactions and, alternatively, a mechanism consisting of four global reactions.

TL;DR: In this paper, the mean and rms of fluctuations of temperature, density, mixture fraction, and the mass fractions of CH/sub 4, O/sub 2, N/sub 1/2, H/sub 3, CO, and CO/sub 6/O were measured in turbulent non-premixed flames of methane near extinction.

TL;DR: In this paper, the authors used the Raman-Rayleigh scattering technique in the blue (visibly soot free) regions of turbulent non-premixed flames of methane close to extinction.

TL;DR: In this article, a laminar flamelet model is applied to turbulent, recirculating premixed combustion in a jet-stirred conical reactor, and the complete statistical description of the thermochemistry is obtained from a one point probability density function (pdf) and detailed chemical kinetic lamin-ar flame structure.

TL;DR: In this article, a computer program has been developed to model the experimental data using a chemical kinetic reaction mechanism, which is able to reproduce the experimental results, although some discrepancies are observed for the minor products, particularly for acetylene.

TL;DR: In this paper, a numerical model and a detailed chemical kinetic reaction mechanism for n-pentane oxidation in a well-stirred reactor is examined, using a simulation model and detailed chemical reaction mechanism.

TL;DR: In this article, the authors developed a description for the propagation of an unsupported, unsteady, multidimensional detonation wave for an explosive with a fully resolved reaction zone and a polytropic equation of state.

TL;DR: In this paper, a new mixing rule for calculating lower flammability limits for mixtures at elevated temperatures was suggested, based on the established equations for each gas component in the mixture.

TL;DR: In this paper, the authors present an experimental study that shows departures from chemical equilibrium in a hydrogen-air flame, which is often erroneously considered to have an infinitely fast chemical rate and therefore to be at chemical equilibrium.

TL;DR: In this paper, the authors compared the predicted and measured data for all test cases and found that the observed trends of distributions of temperature and of species concentrations are generally predictable and that the combustion of pulverized coal can be completed in a CO2O2 atmosphere over a range of CO2-to-O2 mole ratios between 2.23 and 3.65.

TL;DR: In this article, the authors used planar images of CH/sub 4/ mass fraction in the developing region (x/d less than or equal to 17) of an isothermal jet to calculate instantaneous, mean, root mean square (rms), probability density functions (PDFs), and correlations of scalar dissipation and a scalar.

TL;DR: In this article, it is shown that stable combustion can be maintained in spouted beds at fuel concentrations greatly in excess of the rich limit of flammability, which makes it possible to minimize the fraction of fuel used for heat release in any high-temperature partial oxidation, pyrolysis, or other reaction in which the remainder of the fuel is to be processed.

TL;DR: In this paper, the effects of the droplet size and the equivalence ratio on the ignition of monodisperse n-heptane and methanol sprays at atmospheric pressure were investigated using a capacitive discharge spark ignition system.

TL;DR: In this article, the Taylor microscale and the laminar burning velocity of a single cylinder spark-ignition engine were determined as a function of equivalence ratio and engine speed.

TL;DR: In this article, direct measurements have been made of four of the six terms in the exact form of the turbulent kinetic energy (TKE) equation within a premixed turbulent flame, in order to understand how combustion interacts with the turbulence.

TL;DR: In this article, the dimensionless number Πs describing the local entropy in a quenched flame is found to be Π s∼(Ped0)−2, where s = s l 2 k, l = α S u 0 (a characteristic length), k thermal conductivity, α thermal diffusivity, Su0 the adiabatic laminar flame speed at the unburned gas temperature, Pe d 0 = S u0 D α the flame Peclet number, and D the quench distance.

TL;DR: In this paper, a simple model is used to account for CO/sub 2/ formation that results in overall combustion rate parameters that agree well with the measured particle temperatures and carbon mass-loss profiles.

TL;DR: In this paper, a high velocity premixed turbulent flow of air and methane was ignited and stabilized by a parallel flow of hot gases ( u = 110 m/s, T = 2000K).

TL;DR: In this article, a simple model describing chemical reaction in a turbulent shear layer is put in quantitative form and the model predictions compared with experiment The reactants are not pre-mixed and the flow is two-dimensional The dependence of the amount of product in the layer on the Schmidt, Reynolds, and Damkohler numbers and on the======stoichiometric ratio is exhibited explicitly in the model The first two parameters appear as the product (ScRe) and influence that part of the reaction taking place in strained laminar flames

TL;DR: In this article, the appearance and behavior of combustion-generated ions in rich flames of acetylene were modeled and the dominant ion, C3H3+, was found to be produced from CHO+ by ion-molecule reactions rather than by direct chemiionization.

TL;DR: In this article, the behavior of major ions in lean and close-to-stoichiometric acetylene flames was modeled using a set of chemical reactions, including reactions for oxidation, pyrolysis, chemiionization, ion-molecule reactions, and charge recombination.

TL;DR: In this paper, the authors present the results of experimental studies on the venting of gaseous and dust explosions in a 22 1 spherical vessel connected to a duct, where the origin of the acoustic oscillations is not clear and their occurrence can be prevented by initial turbulence.

TL;DR: In this article, the effect of addition of a variety of gases to the silane combustion which proceeds through the following two gross reactions, SiH4 + O2 → SiO2(s) + 2H2