Laminar Soot Processes (Lsp)

Laminar Soot Processes (Lsp) PDF Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781720608042
Category :
Languages : en
Pages : 58

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Book Description
This is the final report of a research program considering the structure and the soot surface reaction properties of laminar nonpremixed (diffusion) flames. The study was limited to ground-based measurements of buoyant laminar jet diffusion flames at pressures of 0.1-1.0 atm. The motivation for the research is that soot formation in flames is a major unresolved problem of combustion science that influences the pollutant emissions, durability and performance of power and propulsion systems, as well as the potential for developing computational combustion. The investigation was divided into two phases considering the structure of laminar soot-containing diffusion flames and the soot surface reaction properties (soot surface growth and oxidation) of these flames, in turn. The first phase of the research addressed flame and soot structure properties of buoyant laminar jet diffusion flames at various pressures. The measurements showed that H, OH and O radical concentrations were generally in superequilibrium concentrations at atmospheric pressure but tended toward subequilibrium concentrations as pressures decreased. The measurements indicated that the original fuel decomposed into more robust compounds at elevated temperatures, such as acetylene (unless the original fuel was acetylene) and H, which are the major reactants for soot surface growth, and that the main effect of the parent fuel on soot surface growth involved its yield of acetylene and H for present test conditions. The second phase of the research addressed soot surface reaction properties, e.g., soot surface growth and surface oxidation. It was found that soot surface growth rates in both laminar premixed and diffusion flames were in good agreement, that these rates were relatively independent of fuel type, and that these rates could be correlated by the Hydrogen-Abstraction/Carbon-Addition (HACA) mechanisms of Colket and Hall (1994), Frenklach et al. (1990,1994), and Kazakov et al. (1995). It was also fou

Laminar Soot Processes (Lsp)

Laminar Soot Processes (Lsp) PDF Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781720608042
Category :
Languages : en
Pages : 58

Get Book Here

Book Description
This is the final report of a research program considering the structure and the soot surface reaction properties of laminar nonpremixed (diffusion) flames. The study was limited to ground-based measurements of buoyant laminar jet diffusion flames at pressures of 0.1-1.0 atm. The motivation for the research is that soot formation in flames is a major unresolved problem of combustion science that influences the pollutant emissions, durability and performance of power and propulsion systems, as well as the potential for developing computational combustion. The investigation was divided into two phases considering the structure of laminar soot-containing diffusion flames and the soot surface reaction properties (soot surface growth and oxidation) of these flames, in turn. The first phase of the research addressed flame and soot structure properties of buoyant laminar jet diffusion flames at various pressures. The measurements showed that H, OH and O radical concentrations were generally in superequilibrium concentrations at atmospheric pressure but tended toward subequilibrium concentrations as pressures decreased. The measurements indicated that the original fuel decomposed into more robust compounds at elevated temperatures, such as acetylene (unless the original fuel was acetylene) and H, which are the major reactants for soot surface growth, and that the main effect of the parent fuel on soot surface growth involved its yield of acetylene and H for present test conditions. The second phase of the research addressed soot surface reaction properties, e.g., soot surface growth and surface oxidation. It was found that soot surface growth rates in both laminar premixed and diffusion flames were in good agreement, that these rates were relatively independent of fuel type, and that these rates could be correlated by the Hydrogen-Abstraction/Carbon-Addition (HACA) mechanisms of Colket and Hall (1994), Frenklach et al. (1990,1994), and Kazakov et al. (1995). It was also fou

Soot Formation in Laminar Jet Diffusion Flames

Soot Formation in Laminar Jet Diffusion Flames PDF Author: Peter Bradford Sunderland
Publisher:
ISBN:
Category :
Languages : en
Pages : 262

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Book Description


Sixth International Microgravity Combustion Workshop

Sixth International Microgravity Combustion Workshop PDF Author:
Publisher:
ISBN:
Category : Combustion
Languages : en
Pages : 490

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Experimental and Numerical Contributions to Soot Production in Laminar Axisymmetric Diffusion Flames

Experimental and Numerical Contributions to Soot Production in Laminar Axisymmetric Diffusion Flames PDF Author: Felipe Andrés Escudero Barros
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description
An experimental study was performed with the main objective of characterizing soot production for different oxygen indices (OIs) in normal (NDFs) and inverse (IDFs) diffusion flames. Specific absorption-emission based methods were developed, implemented and validated to measure soot volume fraction and temperature. It was found that for IDFs, an increase on the OI produces an enhancement of soot formation but does not affect oxidation processes, leading to an increase on soot volume fraction and radiant fraction. In addition, a scaling analysis based on the smoke point (SP) resulted on a unified behavior for ethylene, propane and butane fueled NDFs in terms of flame height, soot volume fraction and radiant fraction at SP. In a second step, a numerical study was performed with the main objective of evaluating the predictive capabilities of the sectional method (SM) and three methods of moments (MOMs) for the resolution of the population balance equation (PBE) for soot particle size distribution (PSD). For this purpose, the MOMs were added to an existing parallel code for simulating laminar axisymmetric diffusion flames. The SM was able to reproduce the available experimental data whereas the MOMs were not able to predict details of soot morphology with the same level of accuracy. An analysis on the main differences between the SM and MOMs was performed. The main issue identified for the MOMs was the inability to satisfy the assumption of conservation of number density of primary particles and number of primary particles per aggregate during soot surface processes.

Microgravity Combustion

Microgravity Combustion PDF Author: Howard D. Ross
Publisher: Elsevier
ISBN: 0080549977
Category : Technology & Engineering
Languages : en
Pages : 601

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Book Description
This book provides an introduction to understanding combustion, the burning of a substance that produces heat and often light, in microgravity environments-i.e., environments with very low gravity such as outer space. Readers are presented with a compilation of worldwide findings from fifteen years of research and experimental tests in various low-gravity environments, including drop towers, aircraft, and space.Microgravity Combustion is unique in that no other book reviews low- gravity combustion research in such a comprehensive manner. It provides an excellent introduction for those researching in the fields of combustion, aerospace, and fluid and thermal sciences. * An introduction to the progress made in understanding combustion in a microgravity environment* Experimental, theoretical and computational findings of current combustion research* Tutorial concepts, such as scaling analysis* Worldwide microgravity research findings

Columbia

Columbia PDF Author: Philip Chien
Publisher: Springer Science & Business Media
ISBN: 038727149X
Category : Science
Languages : en
Pages : 465

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Book Description
In ‘Columbia: Final Voyage’ aerospace writer Philip Chien, who has over 20 years’ experience covering the US space program, provides a unique insight into the crew members who lost their lives in the Columbia disaster. Chien interviewed all seven crew members several times and got to know them as individuals. He reviews in detail their training, their scientific work and other activities during their successful 16-day flight, the background of the accident itself and a detailed first-hand account of what happened that fateful day in February 2003. The author provides a comprehensive and personal look at both the Columbia astronauts and the STS-107 mission, together with a behind-the-scenes account of other people involved in the mission and their personal reactions to the accident. Forward by Jonathan B. Clark, widower of Columbia astronaut Laurel Clark Introduction by Apollo 11 astronaut Buzz Aldrin

Fourth International Microgravity Combustion Workshop

Fourth International Microgravity Combustion Workshop PDF Author:
Publisher:
ISBN:
Category : Combustion
Languages : en
Pages : 546

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Chemical and Physical Processes in Combustion

Chemical and Physical Processes in Combustion PDF Author: Combustion Institute (U.S.). Eastern States Section. Fall Technical Meeting
Publisher:
ISBN:
Category : Combustion
Languages : en
Pages : 464

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The Spacelab Story

The Spacelab Story PDF Author: Ben Evans
Publisher: Springer Nature
ISBN: 3031534492
Category :
Languages : en
Pages : 450

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Book Description


Research & Technology 1997

Research & Technology 1997 PDF Author:
Publisher: DIANE Publishing
ISBN: 1428918256
Category :
Languages : en
Pages : 190

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Book Description