Author: Bo TianPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Laser Diagnostics of Soot in Hydrocarbon Diffusion Flames
Author: Bo TianLaser Diagnostic Analyses of Sooting Flames
Author: G. M. DobbsPublisher:
ISBN:
Category :
Languages : en
Pages : 50
Book Description
Temperature distribution and soot particle size distributions have been measured in axisymmetric, laminar, diffusion flames in order to provide the basis for modelling the influence of fuel structure and temperature on soot formation. This document is the final report and management summary for the joint activities of UTRC and Princeton University. Coherent anti-Stokes Raman spectroscopy (CARS) was used for non-intrusive determination of temperature. Soot particle size and number densities were determined by Mie scattering. The experimental results were then applied to current models of soot formation in an effort to determine the physical and chemical basis for fuel structure and temperature effects on soot formation in diffusion flames. In the course of this first application of CARS and Mie diagnostics to diffusion flames, a large number of questions was raised in regard to the structure of particulate-laden diffusion flames. Measured distributions were compared with a numerical flame-sheet model. Originator-supplied key words include: Soot formation, Diffusion flames, Flame structure, Temperatures in diffusion flames, CARS temperature measurement.
Investigation of Soot Processes in Turbulent Nonpremixed Hydrocarbon Flames Based on Laser Scattering and Extinction Experiments
Author: Bo YangPublisher:
ISBN:
Category : Combustion engineering
Languages : en
Pages : 304
Book Description
"The principal objective of this study was to investigate the fundamentals of various soot processes within turbulent non-premixed flames using non-intrusive laser diagnostics. Unconfined burners with different fuels in atmospheric-pressure air were selected to collect data in well-defined turbulent flames. Laser scattering at two angles and extinction experiments were conducted and interpreted based on an optical theory which can properly account for the actual fractal morphology of soot aggregates ... with the ultimate objective of advancing the predictions of fine-particulate matter in practical combustion applications"--Introduction, leaves 16-17.
Laser Measurements of Soot and CO Production in Time-Varying, Hydrocarbon Diffusion Flames
Author: C. R. ShaddixSoot Formation, Transport, and Radiation in Unsteady Diffusion Flames
Author: Robert W. ScheferPublisher:
ISBN:
Category :
Languages : en
Pages : 48
Book Description
Fires pose the dominant risk to the safety and security of nuclear weapons, nuclear transport containers, and DOE and DoD facilities. The thermal hazard from these fires primarily results from radiant emission from high-temperature flame soot. Therefore, it is necessary to understand the local transport and chemical phenomena that determine the distributions of soot concentration, optical properties, and temperature in order to develop and validate constitutive models for large-scale, high-fidelity fire simulations. This report summarizes the findings of a Laboratory Directed Research and Development (LDRD) project devoted to obtaining the critical experimental information needed to develop such constitutive models. A combination of laser diagnostics and extractive measurement techniques have been employed in both steady and pulsed laminar diffusion flames of methane, ethylene, and JP-8 surrogate burning in air. For methane and ethylene, both slot and coannular flame geometries were investigated, as well as normal and inverse diffusion flame geometries. For the JP-8 surrogate, coannular normal diffusion flames were investigated. Soot concentrations, polycyclic aromatic hydrocarbon (PAH) laser-induced fluorescence (LIF) signals, hydroxyl radical (OH) LIF, acetylene and water vapor concentrations, soot zone temperatures, and the velocity field were all successfully measured in both steady and unsteady versions of these various flames. In addition, measurements were made of the soot microstructure, soot dimensionless extinction coefficient (&), and the local radiant heat flux. Taken together, these measurements comprise a unique, extensive database for future development and validation of models of soot formation, transport, and radiation.
Laser Diagnostics for Combustion Temperature and Species
Author: Alan C. EckbrethPublisher: CRC Press
ISBN: 9789056995324
Category : Technology & Engineering
Languages : en
Pages : 636
Book Description
Focusing on spectroscopically-based, spatially-precise, laser techniques for temperature and chemical composition measurements in reacting and non-reacting flows, this book makes these powerful and important new tools in combustion research
Laser-Induced Incandescence of Soot for High Pressure Combustion Diagnostics
Author: Daniel Dennis Emile CormierPublisher:
ISBN: 9780494765098
Category :
Languages : en
Pages :
Book Description
Laser Diagnostics and Modeling of Combustion
Author: Kazuo IinumaPublisher: Springer
ISBN:
Category : Science
Languages : en
Pages : 386
Book Description
Laser-based Diagnostics for Transient Species in Hydrocarbon Flames
Author: Richard CopelandPublisher:
ISBN:
Category : Hydrocarbons
Languages : en
Pages : 0
Book Description
Detection of chemically important transient species is crucial to understanding the mechanism of hydrocarbon combustion. Though they often occur in low concentrations, these species determine the pathways and rates of many reaction steps. In this report we describe our efforts to develop and quantify diagnostic methods to measure these species in flames. We will describe methods to detect CH, CH3, C2H2, CH2, and HO2; the first four species have successfully been observed in flames during this project. The detection techniques we use are laser-induced fluorescence (LIF) and absorption techniques including photoacoustic detection spectroscopy (PAD). The polyatomic molecules mentioned above are much more difficult to detect than the diatomic molecules CH and OH, and we have developed and used new variations on the basic techniques to achieve the desired sensitivity. In this research, we improved diagnostic techniques for the radicals mentioned above, detected species not previously observed in the flame environment, and increased our knowledge of the important species in hydrocarbon combustion.
Author: Steven George Hall