Physical Sciences and Mathematics Commons^™

Infiltration-Controlled Combustion Of Lithium And Magnesium Powders And Reactions Of Lithium With Oxygen And Carbon Dioxide, Kevin Samuel Estala Rodriguez

Open Access Theses & Dissertations

Chemical heat integrated power systems are of great interest for space missions where solar energy, nuclear energy, and batteries are not available or are not practical to use. A new concept of a power system is a metal combustor coupled with a chemical oxygen generator, where the generated oxygen infiltrates through the metal powder or combustion products. The combustion of lithium and magnesium powders under these conditions has not been studied yet. The present work investigates combustion of magnesium powder and stabilized lithium metal powder (SLMP) ignited by a laser inside a closed chamber filled with O2 or CO2. It …

Characterization Of A Flex-Fuel Oxy-Combustion System Through Experimental Investigation And Computational Modeling, Md Mohieminul I. Khan

Open Access Theses & Dissertations

Oxy-fuel combustion has the potential to offer high thermal efficiency and lower pollutants emission compared to other existing combustion technologies. More than 63% of the worldâ??s electricity is produced by fossil fuel combustion which also is the major reason for greenhouse gas emissions. Oxy combustion offers a solution to it. Oxy combustion uses pure oxygen as an oxidizer instead of air which eliminates the NOx and SOx products from the exhaust. In oxy-combustion flue gas mainly consists of CO2 and water vapor. Furthermore, combustion in presence of pure oxygen results in higher flame temperature and hence promises higher thermal efficiency. …

Direct Simulation And Reduced-Order Modeling Of Premixed Flame Response To Acoustic Modulation, Zheng Qiao

Theses and Dissertations

This dissertation introduces a general, predictive and cost-efficient reduced-order modeling (ROM) technique for characterization of flame response under acoustic modulation. The model is built upon the kinematic flame model–G-equation to describe the flame topology and dynamics, and the novelties of the ROM lie in i) a procedure to create the compatible base flow that can reproduce the correct flame geometry and ii) the use of a physically-consistent acoustic modulation field for the characterization of flame response. This ROM addresses the significant limitations of the classical kinematic model, which is only applicable to simple flame configurations and relies on ad-hoc models …

Distribution And Occurrence Of Uranium In Coal And Its Migration Behavior During The Coal Utilization, Wang Wenfeng, Wang Wenlong, Liu Shuangshuang, Bai Hongyang, Wang Yulong, Duan Piaopiao, Qin Kemin, Chen Yilin

Coal Geology & Exploration

Coal and uranium resources are closely related in spatial disposition as well as mineralization, and the reasonable development, utilization and pollution control of them play an essential role in the sustainable development of our national economy and society. Based on a large number of literature research and the previous results of our research group, some conclusions were drawn with regard to the distribution and occurrence of uranium in coal `and its migration in the process of coal preparation, combustion and leaching:(1) The enrichment and mineralization of uranium in coal has reflected the evolution of coal-forming tectonics:The U-rich coal in Southwest …

Numerical Simulation About Fuel Injection Source Location Impacting On Turbulent Combustion Process, Sun Hui, Guangcheng Cai, Jiang Lin, Shibo Wang

Journal of System Simulation

Abstract: Fuel injection source location has very important influence on combustion process. It determines the location of the furnace flame. The three dimensional model of the furnace was established by the numerical simulation method. Under different conditions, the fuel injection source location on the temperature field within the furnace, the pollutant concentration field, and the flow field distribution inside the furnace combustion process were investigated. The results were compared and analyzed. After analysis, the results show that the fuel injection source location from 1.1 ~ 1.5 meter process of change, the average temperature within the furnace continue to rise, the …

Computational Analysis Of A New Planar Mixing Layer Flame Configuration To Study Soot Inception, Carmen Ciardiello

Honors Scholar Theses

The production of soot is omnipresent in society today. Soot is the product of many of the combustion processes that provide the bulk of the usable energy throughout the world. Furthermore, soot particulate poses a great danger to both the environment and all forms of life on Earth. It has proven to pollute ecosystems, foster health problems for human beings, and degrade air quality [1].

These dangers make studying and understanding soot particulate paramount for improving the quality of life. Thus, this study introduces a new flame configuration for studying soot inception. Presently, various common flame configurations have been found …

Bakken Flares And Satellite Images, University Of North Dakota. Energy And Environmental Research Center, Xiaodong Zhang

EERC Brochures and Fact Sheets

Fact sheet refuting a magazine article about Bakken gas flares and satellite images. Includes research into gas flares and satellite images by the University of North Dakota and the Energy & Environmental Research Center.

Pulse Power Effects On Transient Plasma Ignition For Combustion, David Wayne Alderman Ii

Electrical & Computer Engineering Theses & Dissertations

Transient plasma ignition (TPI) uses highly non-equilibrium plasmas, driven by less than 100 nanosecond, high-voltage pulses, to initiate combustion. The effects of pulse repetition frequency (PRF) and ultrashort nanosecond rise times on TPI are investigated in this work using lean, stoichiometric, and rich air-fuel mixtures at atmospheric pressure. Experimental data show the transient plasmas driven by ultrashort rise time, high voltage pulses at high PRF’s enhance the combustion of lean or stoichiometric air-methane mixtures in a static chamber. In particular, increasing PRF enhances the combustion performance by means of reduced delay times independent of the equivalence ratio of the air-fuel …

Examination Of Flow Dynamics And Passive Cooling In An Ultra Compact Combustor, Tylor C. Rathsack

Theses and Dissertations

The Ultra Compact Combustor (UCC) promises to greatly reduce the size of a gas turbine engine’s combustor by altering the manner in which fuel is burnt. Differing from the common axial flow combustor, the UCC utilizes a rotating flow, coaxial to the engine’s primary axis, in an outboard circumferential cavity as the primary combustion zone. The present study investigates two key UCC facets required to further this combustor design. The first area of investigation is cooling of the Hybrid Guide Vane (HGV). This UCC specific hardware acts as a combustor center body that alters the exit flow angle and acts …

Characterization And Evaluation Of Cordless Nailer Performance For Liquid And Gaseous Fuels, Mark Carioscio

Master's Theses (2009 -)

The Paslode Cordless XP Framing Nailer is a combustion-powered nail gun that operates using a fuel blend of a propylene and 1-butene. This tool is designed to drive nails using a piston driven by a combustion reaction. The current fuel blend is able to fire approximately 1200 shots per fuel cartridge and match the energy output of pneumatic, corded nailers on the market. This thesis is written with the intent to gain a better understanding of the operation of the tool and how its performance varies when the fuel source is altered. A bizonal combustion model was created to simulate …

Reconstruction Of The 3d Temperature And Species Concentration Spatial Distribution Of A Jet Engine Exhaust Plume Using An Infrared Fourier Transform Spectrometer Hyperspectral Imager, Mason D. Paulec

Theses and Dissertations

The measurement of combustion byproducts is useful for determining pollution of any fuel burning application, efficiency of combustion, and determining detectability of aircraft exhausts. Both intrusive and non-intrusive techniques have been utilized to measure these quantities. For the majority of the non-intrusive techniques, the absorption and emission spectra of the gases are utilized for measurements. For this research, the use of the Telops Infrared Fourier Transform Spectrometer (IFTS) Hyperspectral Imager (HSI) was explored within the scope of combustion diagnostic methods, as an option for remote measurements of a jet turbine to determine concentration of species and temperature of the combustion …

Kinetic Study Of Free Radical-Radical Reactions Of Combustion Importance At Elevated Pressures, Chao Yan

Dissertations

Combustion mechanisms consist of hundreds elementary reactions of free radicals and stable molecules. Radical-radical elementary reactions play important roles due to the high concentration in which free radicals are accumulated in combustion systems. Radical-radical reactions are typically multi-channel. Some of the channels might be of chain propagation or even chain branching nature, while other channels might be of chain termination nature. The relative importance of different channels is pressure dependent. Compared to radical-molecule reactions, radical-radical reactions are much less studied. This is due to the difficulties of well characterized quantitative production of radical species as well as due to the …

Studies In Pressurized Oxy-Combustion: Process Development And Control Of Radiative Heat Transfer, Akshay Gopan

McKelvey School of Engineering Theses & Dissertations

Fossil fuels supply over 80% of the world’s primary energy and more than two-thirds of the world’s electricity. Of this, coal alone accounts for over 41% of the electricity supplied globally. Though coal is globally well-distributed and can provide stable and reliable energy on demand, it emits a large amount of carbon dioxide—a greenhouse gas responsible for global warming. Serious concerns over the implication of the increased global temperature have prompted the investigation into low carbon energy alternatives. The idea of capturing the carbon dioxide emitted from the combustion sources is considered as one of the viable alternatives. This would …

Sub 2 Nm Particle Characterization In Systems With Aerosol Formation And Growth, Yang Wang

McKelvey School of Engineering Theses & Dissertations

Aerosol science and technology enable continual advances in material synthesis and atmospheric pollutant control. Among these advances, one important frontier is characterizing the initial stages of particle formation by real time measurement of particles below 2 nm in size. Sub 2 nm particles play important roles by acting as seeds for particle growth, ultimately determining the final properties of the generated particles. Tailoring nanoparticle properties requires a thorough understanding and precise control of the particle formation processes, which in turn requires characterizing nanoparticle formation from the initial stages. The knowledge on particle formation in early stages can also be applied …

Oxidation Of Substituted Catechols At The Air-Water Interface: Production Of Carboxylic Acids, Quinones, And Polyphenols, Elizabeth A. Pillar, Marcelo I. Guzman

Chemistry Faculty Publications

Anthropogenic activities contribute benzene, toluene, and anisole to the environment, which in the atmosphere are converted into the respective phenols, cresols, and methoxyphenols by fast gas-phase reaction with hydroxyl radicals (HO(•)). Further processing of the latter species by HO(•) decreases their vapor pressure as a second hydroxyl group is incorporated to accelerate their oxidative aging at interfaces and in aqueous particles. This work shows how catechol, pyrogallol, 3-methylcatechol, 4-methylcatechol, and 3-methoxycatechol (all proxies for oxygenated aromatics derived from benzene, toluene, and anisole) react at the air-water interface with increasing O3(g) during τc ≈ 1 μs contact time and contrasts their …

Data Driven Low-Bandwidth Intelligent Control Of A Jet Engine Combustor, Nathan L. Toner

Open Access Dissertations

This thesis introduces a low-bandwidth control architecture for navigating the input space of an un-modeled combustor system between desired operating conditions while avoiding regions of instability and blow-out. An experimental procedure is discussed for identifying regions of instability and gathering sufficient data to build a data-driven model of the system's operating modes. Regions of instability and blow-out are identified experimentally and a data-driven operating point classifier is designed. This classifier acts as a map of the operating space of the combustor, indicating regions in which the flame is in a "good" or "bad" operating mode. A data-driven predictor is also …

Gasoline Confined In Nano-Porous Media, Matthew Giso

Honors Theses

The heat of combustion was determined for gasoline confined in nano-porous media of differing pore size by bomb calorimetry. The heat of combustion of the confined fuels was comparable to that of bulk within the experimental uncertainty. This suggests that all of the confined fuel burns without any flame quenching and no chemical interactions at the interface between pore walls and fuel mitigate combustion.

Experimental Investigation Of Syngas Flame Stability Using A Multi-Tube Fuel Injector In A High Pressure Combustor, Sergio Elzar Maldonado

Open Access Theses & Dissertations

Over 92% of the coal consumed by power plants is used to generate electricity in the United States (U.S.). The U.S. has the world's largest recoverable reserves of coal, it is estimated that reserves of coal will last more than 200 years based in current production and demand levels. Integrated Gasification Combined Cycle (IGCC) power plants aim to reduce the amount of pollutants by gasifying coal and producing synThesis gas. SynThesis gas, also known as syngas, is a product of coal gasification and can be used in gas turbines for energy production. Syngas is primarily a mixture of hydrogen and …

Ionization In Diesel Combustion For On-Board Diagnostics And Engine Control, Tamer Hassan Badawy

Wayne State University Dissertations

Diesel engines have been known for their high thermal efficiency and specific power output, but there is concern about engine-out NOx and particulate matter emissions. To meet the current emission standards, advanced diesel engines are fitted with electronically controlled fuel injection systems and sophisticated and expensive after-treatment devices. Further improvements are still needed to meet future goals in better fuel economy and the more stringent emission standards. In order to meet these goals, there is a need for the control of the combustion process to reduce engine-out emissions in real-time and reduce the demand on the after-treatment devices. This requires …

Investigation Of The Radiative Heat Release Factor Of Premixed Oxy-Syngas Flames, Martin De La Torre

Open Access Theses & Dissertations

A significant part of the United States is being powered by combustion devises relying on coal since it is abundant and is a high emitting source of electricity per unit energy, however; the burning of this fuel is responsible for a significant contribution for the pollutant emissions causing global warming. Because coal is one of the main sources of energy in the U.S. and around the globe, the scientific community has been investigating ways to meet current and future governmental emission requirements. It is now well established that radiating heat from the flame is a major contributor of the heat …

Adiabatic Flame Temperature For Combustion Of Methane Ii, Rebeca Pupo

Undergraduate Journal of Mathematical Modeling: One + Two

We calculate the adiabatic flame temperature of a mixture of methane and oxygen in the presence of a diluent gas then determine the mole fractions of methane without respect to nitrogen and solve for the moles of oxygen present. Knowing the moles of methane and oxygen, allows us to calculate the moles of nitrogen present at four constant mole fractions of nitrogen, and the adiabatic flame temperature is determined from the energy released by the reaction. Lastly, we produce several graphs to compare the adiabatic flame temperatures at different mole fractions of nitrogen.

Development Of The Control And Ignition Systems On A High Pressure Gas Turbine Combustor, Carlos Alejandro Valdez

Open Access Theses & Dissertations

The ignition and control systems of a laboratory scale high-pressure gas turbine combustor were developed in the present work. This work provides a detailed description of the design, development and testing of the remote control system developed for a High Pressure Gas Turbine Combustor (HPTC).

The combustor has the capability to operate at pressures up to 1.5 MPa and temperatures up to 2400 K. It is also designed for a maximum air and fuel flow rates of 81.93 g/s and 35.77 g/s respectively. The fuel used will be CH4 for the early experiments but it is designed to operate using …

Detailed Modeling Of Soot Size Distribution Evolution And Pollutant Formation Inside Aircraft And Diesel Engines, Chowdhury Golam Moniruzzaman

Legacy Theses & Dissertations (2009 - 2024)

Combustion emission of soot and pollutant gas species contributes to poor regional air quality near emission sources and to climate change. It is important to understand the formation mechanism and time evolution of these pollutants inside the combustion engine, through detailed modeling of combustion chemistry and microphysics as well as comparison with observation. In this thesis, two multi-zone gas parcel combustion engine models, one for aircraft engines and another for diesel engines, have been developed to study soot size distribution evolution and pollutant formation inside the engines as well as emissions. The models take into account size-resolved (sectional) soot aerosol …

Lectio Praecursoria, Kari Myöhänen

Kari Myöhänen

Lectio praecursoria: Modelling of combustion and sorbent reactions in three-dimensional flow environment of a circulating fluidized bed furnace

Bazr(0.8)Y(0.2)O(3-Delta)-Nio Composite Anodic Powders For Proton-Conducting Sofcs Prepared By A Combustion Method, Lei Bi, Emiliana Fabbri, Ziqi Sun, Enrico Traversa

Australian Institute for Innovative Materials - Papers

BaZr_0.8Y_0.2O_3-∂ (BZY)-NiO composite powders with different BZY-NiO weight ratios were prepared by a combustion method as anodes for proton-conducting solid oxide fuel cells (SOFCs). After heating to 1100^°C for 6 h, the composite powders were made of a well-dispersed mixture of two phases, BZY and NiO. Chemical stability tests showed that the BZY-NiO anodic powders had good stability against CO₂, whereas comparative tests under the same conditions showed degradation for BaCe_0.7Zr_0.1Y_0.2O_3-∂- NiO, which is at present the most used anode material for proton-conducting …

Experimental And Numerical Investigation Of The Effect Of Fuel Composition On Flame Stability On A Gas Turbine Combustor, Gilberto Corona

Open Access Theses & Dissertations

Gas turbines are used for power generation and aviation all over the world. Fossil fuels remain the main source of energy for the operation of gas turbines but the recent increase in environmental awareness has influenced government agencies to impose stringent limits on pollutant emissions from power generation plants. Pollutant emissions control is one of the major challenges for gas turbine designers. In this study, experimental methods and computational fluid dynamics (CFD) technologies are used to study the problems that arise when coal derived fuels are used in Gas Turbine Combustors.

Gas turbine designers need both experimental data and combustion …

Slides: Energy Development Water Needs Assessment And Water Supply Alternatives And Analysis, Benjamin Harding

The Promise and Peril of Oil Shale Development (February 5)

Presenter: Benjamin Harding, Principal Engineer, AMEC Earth and Environmental

15 slides

Slides: The Logistics And Energy Needs Of Oil Shale Extraction, Alan K. Burnham

The Promise and Peril of Oil Shale Development (February 5)

Presenter: Dr. Alan K. Burnham, Chief Technology Officer, American Shale Oil, LLC

10 slides

Neuro Emission Controller For Minimizing Cyclic Dispersion In Spark Ignition Engines, Pingan He, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

A novel neural network (NN) controller is developed to control spark ignition (SI) engines at extreme lean conditions. The purpose of neurocontroller is to reduce the cyclic dispersion at lean operation even when the engine dynamics are unknown. The stability analysis of the closed-loop control system is given and the boundedness of all signals is ensured. Results demonstrate that the cyclic dispersion is reduced significantly using the proposed controller. The neuro controller can also be extended to minimize engine emissions with high EGR levels, where similar complex cyclic dynamics are observed. Further, the proposed approach can be applied to control …

Studies Of Mixing Processes In Gases And Effects On Combustion And Stability, Frank Paul Kozusko Jr.

Mathematics & Statistics Theses & Dissertations

Three physical models of laminar mixing of initially separated gases are studied. Two models study the effects of the mixing dynamics on the chemical reactions between the gases. The third model studies the structure and stability of a laminar mixing layer in a binary gas. The three models are:

1. Two ideal and incompressible gases representing fuel and oxidizer are initially at rest and separated across an infinite linear interface in a two dimensional system. Combustion, expected as the gases mix, will lead to a rapid rise in temperature in a localized area, i.e. ignition. The mixing of the gases …