Results 181 to 190 of about 26,791 (233)

A Fractal Model of Turbulent Flame Kernel Growth

SAE Technical Paper Series, 1990
<div class="htmlview paragraph">A model of turbulent flame kernel growth has been developed based on the fractal nature of premixed turbulent flame structure. The flame kernel model uses a recently developed heuristic model for the fractal dimension of premixed turbulent flame surfaces in order to predict the flame kernel's structure. The fractal
Domenic A. Santavicca, Deryuh Liou, Gary L. North   +2 more
openaire   +1 more source

Effect of Discharge Energy Distribution on Flame Kernel Development

ASME 2020 Internal Combustion Engine Division Fall Technical Conference, 2020
Abstract The early flame kernel initiation and development are essential to a successful combustion process, especially under lean burn/EGR diluted conditions. Multiple ignition sites strategy has shown promise to secure the flame kernel initiation under extreme engine operating conditions. Two factors are considered to contribute to the
Linyan Wang, Mengzhu Liu, Liguang Li, Ming Zheng, Xiao Yu, Hua Zhu   +5 more
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Analysis of Premixed Turbulent Spherical Flame Kernels

2007
The present study discusses results from a number of DNS simulations of turbulent flame kernels. The description of the chemistry in these calculations was based on the Flamelet Generated Manifolds (FGM) technique. The differences are imposed by varying the turbulence intensity and length scale within the thin reaction zones regime.
Bastiaans, R.J.M., Swart, de, J.A.M., Oijen, van, J.A., Goey, de, L.P.H.   +3 more
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Flame Kernel Development in a Methanol Fueled Engine

SAE Technical Paper Series, 1993
<div class="htmlview paragraph">The combustion behavior in a modem 4-valve engine using a broad range of methanol/gasoline fuel mixtures was studied. The initial flame development was examined by using a spark plug fiber optics probe. Approximately, the kernel expansion speed, S_g, is relatively unchanged from M0 to M40 ...
Peter C. Hinze, Wai K. Cheng
openaire   +1 more source

Growth Rate and Flame Structure of Turbulent Premixed Flame Kernels in Supersonic Flows

54th AIAA Aerospace Sciences Meeting, 2016
A fundamental study of the radial growth and flame surface characteristics of freely propagating spherical flames is conducted in a 50 × 50 mm, M = 1.5 supersonic wind tunnel. Free stream turbulence is enhanced via passive and active turbulence generators upstream of the converging-diverging nozzle.
Bradley A. Ochs, Dan Fries, David E. Scarborough, Suresh Menon   +3 more
openaire   +1 more source

Direct Numerical Simulation of Turbulent Flame Kernels

1999
A combustion DNS code has been developed to solve a fully compressible reacting flow and applied to studying the effects of a turbulent flame kernel. High accuracy numerical techniques have been employed which are 10th order explicit in space and a third order explicit Runge Kutta method in time.
Karl W. Jenkins, R. Stewart Cant
openaire   +1 more source

Flame surface density distribution in turbulent flame kernels during the early stages of growth

Proceedings of the Combustion Institute, 2009
Abstract Direct numerical simulations (DNS) of flame kernels with single-step chemistry are used to asses the influence of the initial turbulent energy spectra on the global evolution of the kernel, and the distribution of flame surface density (FSD) in the flame brush.
T.D. Dunstan, K.W. Jenkins
openaire   +1 more source

The Effects of Initial Flame Kernel Conditions on Flame Development in SI Engine

SAE Technical Paper Series, 1991
<div class="htmlview paragraph">The initial flame kernel behavior in a SI engine was measured by a spark-plug-fiber-optics probe. From these measurements, the flame kernel may be characterized by an expansion speed and a convection velocity. These quantities were correlated with the bum rate on a cycle-to-cycle basis in an engine configurated ...
Yvan Bianco, Wai K. Cheng, John B. Heywood   +2 more
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A regime diagram for premixed flame kernel-vortex interactions

Physics of Fluids, 2007
Direct numerical simulations of flame kernel-vortex interactions are implemented in an axisymmetric configuration using a two-step global mechanism to study the different combustion regimes of the interactions. Four combustion regimes have been identified.
Echekki, Tarek, Kolera-Gokula, Hemanth
openaire   +1 more source

Curvature effects on flame kernels in a turbulent environment

Proceedings of the Combustion Institute, 2002
This paper presents results from the direct numerical simulation (DNS) of flame kernels in various turbulent environments. The flames are fully premixed and propagate through a field of decaying isotropic turbulence. The DNS code solves the fully compressible reacting flow equations using high-order explicit finite differences in space and a third ...
K.W. Jenkins, R.S. Cant
openaire   +1 more source