Results 181 to 190 of about 5,704 (215)

Convection-Diffusion Controlled Laminar Micro Flames

Journal of Heat Transfer, 1994
Small laminar diffusion flames (flame height ≃2–3 mm) established by a fuel jet issuing into a quiescent medium are investigated. It was found that for these flames buoyancy effects disappeared as the flame size decreased (Fr≫1), and diffusive transport of the fuel was comparable to the convective transport of the fuel.
H. Ban, S. Venkatesh, K. Saito
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Laminar diffusion flames under micro-gravity conditions

26th Aerospace Sciences Meeting, 1988
Laminar methane and propane gas-jet diffusion flames have been theoretically and experimentally studied at NASA-Lewis under microgravity conditions. It is noted that laminar diffusion flames are strongly affected by the combined effects of kinetics, radiation, and such transient phenomena as flame ignition, stabilization, and extinction.
RAYMOND EDELMAN, YOUSEF BAHADORI, SANDRA OLSON, DENNIS STOCKER   +3 more
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Experimental characterization of a laminar diffusion flame in micro-gravity

Journal de Chimie Physique et de Physico-Chimie Biologique, 1999
L'etude experimentale d'une flamme de diffusion etablie sur une plaque de PMMA de 50 mm x 50 mm x 10 mm, placee dans un ecoulement force parallele a la surface a ete realisee. Les experiences ont ete principalement realisees dans un environnement de microgravite pour simuler les conditions a bord d'un vaisseau spatial en orbite.
T. Vietoris, P. Joulain, J. L. Torero
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Structure of Micro (Millimeter Size) Diffusion Flames

2008
Tiny jet diffusion flames (called “micro flames” hereafter) with hydrocarbon fuels were established over a submillimeter-diameter hypodermic needle in a quiescent atmosphere. Because of the small flame height, on the order of magnitude of one millimeter, there is hardly any buoyancy effect, and the observed flame shape is almost spherical when Re=O(1).
Yuji Nakamura, Heng Ban, Kozo Saito, Tadao Takeno   +3 more
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Temperature and optimum ionization in the micro diffusion flame

Combustion and Flame, 1983
Abstract The simple method previously proposed for estimating the maximum temperature of a diluted micro hydrogen diffusion flame from its composition index has been examined experimentally, using a thermocouple, and has been shown to be satisfactory in certain selected cases.
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Micro-explosion effects in a laminar water-in fuel spray diffusion flame

Combustion Theory and Modelling, 2020
In this work, we formulate a simple one-dimensional model as a framework for studying the influence of water-in-fuel emulsions on spray diffusion flames.
J. Barry Greenberg, Sahar Shpitz
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Active control of lifted diffusion flames with arrayed micro actuators

Experiments in Fluids, 2005
Active control of a lifted flame issued from a coaxial nozzle is investigated. Arrayed micro flap actuators are employed to introduce disturbances locally into the initial shear layer. Shedding of large-scale vortex rings is modified with the flap motion, and the flame characteristics such as liftoff height, blowoff limit, and emission trend, are ...
N. Kurimoto, Y. Suzuki, N. Kasagi
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Structure and Dynamics of Laminar Jet Micro-Slot Diffusion Flames

Journal of Heat Transfer, 2002
Results of an experimental investigation into the behavior of laminar jet diffusion flames, produced using micro-slot burner ports, are presented. Under certain conditions, the cross-sectional shape of micro-slot flames is qualitatively similar to the cross-sectional shape of circular burner port flames produced in an environment where molecular ...
John Baker, Mark E. Calvert, David W. Murphy   +2 more
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On micro-buoyancy spherical diffusion flames and a double luminous zone structure of the hydrogen/methane flame

Symposium (International) on Combustion, 1998
Almost spherically symmetry diffusion flames of substantial dimension (diameter ∼ several centimeters) were established in earth gravity by ejecting an O 2 /N 2 mixture from a porous sphere into a subatmospheric pressure environment consisting of low-molecular-weight fuels such as methane and hydrogen.
C.J. Sung, D.L. Zhu, C.K. Law
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Oscillatory extinction of spherical diffusion flames: Micro-buoyancy experiment and computation

Proceedings of the Combustion Institute, 2002
The transient extinction behavior of near-limit spherical diffusion flames under microbuoyancy conditions was experimentally investigated. An inverse flame configuration was employed with the oxidizer being ejected from a porous sphere burner into a fuel (H 2 ) environment in a low-pressure (0.096 atm) chamber to effectively minimize buoyancy.
S.W. Yoo, E.W. Christiansen, C.K. Law
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