Author: Gary L. BormanPublisher:
ISBN:
Category :
Languages : en
Pages : 196
Book Description
An Experimental and Theoretical Study of the Vaporization of Single Fuel Droplets
Author: Gary L. BormanExperimental and Theoretical Study of Droplet Vaporization in a High Pressure Environment
Author: Jorg StengeleAn Experimental Investigation of the Effect of Fuel Droplet Size on the Vaporization Process in a Turbulent Environment at Elevated Temperature and Pressure
Author: Cameron Mark VerweyPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
The performance of liquid-fuelled spray combustion systems has a massive impact on the efficiency of energy production in many sectors across the globe. Realistic combustors generate sub 100-μm droplets and operate under high pressure and temperature in strong turbulence. Investigations into droplet evaporation and combustion provide fundamental knowledge and validation data regarding the behaviour of sprays, and although single droplet approaches have been a staple of energy research for many decades, there is little information regarding the effect of turbulence and initial diameter, especially micro-sized, on droplet evaporation rates. The present experimental study develops, interprets, and correlates the results of almost 500 tests performed on isolated heptane and decane droplets. Droplets in the range of 110 - 770 μm (initial diameter) were generated and suspended on small intersecting micro-fibers in a spherical fan-driven chamber and exposed to quasi-zero mean turbulence of intensity up to 1.5 m/s, temperatures ranging from 25 - 100°C, and pressures between 1 and 10 bar. The results indicate that droplet size has a major influence on evaporation rate, as measured by the temporal reduction in droplet surface area, when the environment is turbulent. Evaporation rates increased with both initial diameter and turbulence intensity at all test conditions. The effectiveness of turbulence, defined as the ability of turbulence to improve the evaporation rate over the rate of a stagnant droplet at identical ambient conditions, increased with pressure but decreased with temperature. Both the ratio of Kolmogorov length scale to droplet diameter and the theoretical molar concentration gradient of fuel at the droplet surface are found to be excellent predictors of turbulence effectiveness. Correlation approaches utilizing a turbulent Reynolds number or a vaporization Damköhler number are suggested to predict the evaporation rate of a single droplet exposed to a purely turbulent flow field.
Experimental Studies of the Vaporization of Droplets in Heated Air at High Pressures
Author: Publisher:
ISBN:
Category : High pressure (Science)
Languages : en
Pages : 434
Book Description
Combustion Theory
Author: Forman A. WilliamsPublisher: CRC Press
ISBN: 0429973683
Category : Science
Languages : en
Pages : 549
Book Description
Combustion Theory delves deeper into the science of combustion than most other texts and gives insight into combustions from a molecular and a continuum point of view. The book presents derivations of the basic equations of combustion theory and contains appendices on the background of subjects of thermodynamics, chemical kinetics, fluid dynamics, and transport processes. Diffusion flames, reactions in flows with negligible transport and the theory of pre-mixed flames are treated, as are detonation phenomena, the combustion of solid propellents, and ignition, extinction, and flamibility pehnomena.
A Numerical Study of Spherical Droplet Vaporization in a High Pressure Environment
Author: Eric Warren CurtisTheoretical Studies on Heterogeneous Combustion. Progress Report, March 1, 1981-December 15, 1981
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
In most of the liquid-fueled chemical power plants the fuel is usually introduced into the combustor in the form of a spray jet consisting of an ensemble of droplets. The spray subsequently ignites and burns, releasing chemical energy to perform work and, at the same time, producing trace pollutants which are subsequently exhausted. In order to improve the combustor performance in terms of cleanliness and efficiency, understanding of the combustion characteristics of fuel spray is essential. The present program aims to study the various heterogeneous processes involved during (1) vaporization, ignition, deflagration, and extinction of single fuel droplets in the reactive environment simulating the spray interior, and (2) the vaporization, ignition, and combustion of the spray as a whole. The approach is primarily theoretical, although occasionally simple experiments have been conducted to complement the theoretical predictions. The following projects were completed this quarter and are described in this report: explosions with chain branching; assessment of importance of gas-phase transient diffusion in droplet combustion; droplet flame structure with combined forced and buoyant convection; and review of articles on droplet vaporization and combustion.
Chemical Kinetics in Combustion and Reactive Flows: Modeling Tools and Applications
Author: V. I. NaoumovPublisher: Cambridge University Press
ISBN: 1108427049
Category : Science
Languages : en
Pages : 449
Book Description
Introduces advanced mathematical tools for the modeling, simulation, and analysis of chemical non-equilibrium phenomena in combustion and flows, following a detailed explanation of the basics of thermodynamics and chemical kinetics of reactive mixtures. Researchers, practitioners, lecturers, and graduate students will find this work valuable.
Theoretical and Experimental Studies on Evaporation and Combustion of Multicomponent Droplets in Reduced Gravity
Author: Israel AharonDust Explosion Dynamics
Author: Russell A. OglePublisher: Butterworth-Heinemann
ISBN: 0128038292
Category : Technology & Engineering
Languages : en
Pages : 687
Book Description
Dust Explosion Dynamics focuses on the combustion science that governs the behavior of the three primary hazards of combustible dust: dust explosions, flash fires, and smoldering. It explores the use of fundamental principles to evaluate the magnitude of combustible dust hazards in a variety of settings. Models are developed to describe dust combustion phenomena using the principles of thermodynamics, transport phenomena, and chemical kinetics. Simple, tractable models are described first and compared with experimental data, followed by more sophisticated models to help with future challenges. Dr. Ogle introduces the reader to just enough combustion science so that they may read, interpret, and use the scientific literature published on combustible dusts. This introductory text is intended to be a practical guide to the application of combustible dust models, suitable for both students and experienced engineers. It will help you to describe the dynamics of explosions and fires involving dust and evaluate their consequences which in turn will help you prevent damage to property, injury and loss of life from combustible dust accidents. Demonstrates how the fundamental principles of combustion science can be applied to understand the ignition, propagation, and extinction of dust explosions Explores fundamental concepts through model-building and comparisons with empirical data Provides detailed examples to give a thorough insight into the hazards of combustible dust as well as an introduction to relevant scientific literature