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<p>Pollution problems have drawn worldwide awareness and become significantly important now. Particulate matter (PM) emission is one of the key pollution issues. Particulate matter has a significant impact on the environment and human health, especially particle sizes that range below 10μm. Researches continuously work an improvement of fine particulate matter collections emitted from all kinds of sources, such as automobiles, industrial combustion, etc. Governments in many countries are planning to regulate the PM emission from the existing PM_10 (particle diameter<10μm) to new limits PM_2.5 (particle diameter<2.5μm) within the next few years. For this reason, present PM control system needs to be improved.</p><p>The objective of this work is to develop a dust flow separator type electrostatic precipitator (DFS-ESP) for the effective control of fine particulate matter emission from natural gas combustions. The characteristic of PM emitted from natural gas combustion is studied, and the performance of a DFS-ESP is evaluated by experiments and numerical predictions.</p><p>An experiment was conducted for natural gas combustion exhaust flow rates from 2.5 to 9 Nm^3/h, ESP applied voltages from 0 to 30kV, and gas temperature from 80 to 160°C. A series of particle measurements were conducted at upstream, downstream and middle of the DFS-ESP system by an optical particle counter for particle mass density, and by condensation nucleate particle counter for particle size distributions and particle number density. Particle sampled from the natural gas combustion system was also analyzed by an environmental scanning electron microscope (ESEM) technique. Flow velocity profile and pressure drop of the DFS-ESP were measured by a Pitot tube and diaphragm type pressure transducer, respectively.</p><p>The experimental results show that the particle size emitted from natural gas combustion ranges from 17 to 300nm in diameter, and the volume density is approximately from 5 x 10^8 #pt/m^3 to 5 x 10^9 #pt/m^3 depending on the combustion conditions. The dust flow separator can concentrate 90% of fine particles in 1 to 3% of the gas flow and divert it from the main flow to the ESP section where the particles can be removed. In terms of overall particle collection efficiency, the DFS-ESP system can remove up to 90% of the particles based on the number density. The pressure drop across the DFS-ESP is observed to be lower than lPa for the present range of flow rate, which is within acceptable limits for industrial applications.</p> / Thesis / Master of Applied Science (MASc)

<p> Pollution problems have drawn worldwide awareness and become significantly important now. Particulate matter (PM) emission is one of the key pollution issues. Particulate matter has a significant impact on the environment and human health, especially particle sizes that range below lOJJ.m. Researches continuously work an improvement of fine particulate matter collections emitted from all kinds of sources, such as automobiles, industrial combustion, etc. Governments in many countries are planning to regulate the PM emission from the existing PM10 (particle diameter<10μm) to new limits PM2.5 (particle diameter<2.5μm) within the next few years. For this reason, present PM control system needs to be improved. </p> <p> The objective of this work is to develop a dust flow separator type electrostatic precipitator (DFS-ESP) for the effective control of fine particulate matter emission from natural gas combustions. The characteristic of PM emitted from natural gas combustion is studied, and the performance of a DFS-ESP is evaluated by experiments and numerical predictions. </p> <p> An experiment was conducted for natural gas combustion exhaust flow rates from 2.5 to 9 Nm^3/h, ESP applied voltages from 0 to 30kV, and gas temperature from 80 to 160°C. A series of particle measurements were conducted at upstream, downstream and middle of the DFS-ESP system by an optical particle counter for particle mass density, and by condensation nucleate particle counter for particle size distributions and particle number density. Particle sampled from the natural gas combustion system was also analyzed by an environmental scanning electron microscope (ESEM) technique. Flow velocity profile and pressure drop of the DFS-ESP were measured by a Pitot tube and diaphragm type pressure transducer, respectively. </p> <p> The experimental results show that the particle size emitted from natural gas combustion ranges from 17 to 300nm in diameter, and the volume density is approximately from 5 x 10^8 #pt/m^3 to 5 x 109 #pt/m^3 depending on the combustion conditions. The dust flow separator can concentrate 90% of fine particles in 1 to 3% of the gas flow and divert it from the main flow to the ESP section where the particles can be removed. In terms of overall particle collection efficiency, the DFS-ESP system can remove up to 90% of the particles based on the number density. The pressure drop across the DFS-ESP is observed to be lower than lPa for the present range of flow rate, which is within acceptable limits for industrial applications. </p> / Thesis / Master of Applied Science (MASc)

<p> Increasingly stringent legislation governing the emissions of diesel engine particulate matter (DPM) has required the development of technological improvements to diesel engines, fuels and exhaust treatments. A main focus of diesel particulate matter abatement is on exhaust after treatment, that consists of the removal of particulate matter from the exhaust gas after it exits the engine. This is currently accomplished with regenerative diesel particulate traps that are effective at removing DPM, but are costly and introduce a significant pressure drop in the exhaust flow.</p> <p> The objective of this study was to evaluate the potential of a novel particulate removal system consisting of a particulate flow separator combined with electrostatic precipitators (ESPs). Previous application of this system to natural gas emissions resulted in collection efficiencies larger than 90% with negligible pressure drop.</p> <p> The ESPs used in the proposed flow separator-ESP were characterized and have collection efficiencies of up to 99% at the flow rates studied. The flow separator-ESP was characterized with a straight inlet section and an expanding inlet section. The collection efficiency of the flow separator-ESP configured with the expanding inlet section was up to 60% for a flow rate of 2.5 kg/hr, that corresponded to laminar flow with Reynolds number of 1100. Collection efficiencies on the order of 20% were obtained for exhaust flow rates of 3.75 kg/hr (Re = 1500) and 5.0 kg/hr (Re = 2100) for both inlet configurations, and 2.5 kg/hr with the straight inlet. The effectiveness of the current design is limited by exhaust flow rate.</p> <p> The diesel exhaust gas was sampled using a partial flow dilution tunnel developed specifically for this study. The dilution ratio for this system can be estimated to within ±10% using volumetric flow measurements. It was found that changes in the dilution and sampling velocity ratios for diesel exhaust have some effect on measured particulate matter mass concentrations.</p> / Thesis / Master of Applied Science (MASc)

Bipolar plate material and fabrication costs make up a significant fraction of the total cost in a polymer electrolyte membrane fuel cell stack. In an attempt to reduce these costs, a novel manufacturing method was developed for use with composite materials. Conductive fillers were mixed with a polypropylene binder and molded into single cell monopolar plates. A fuel cell test stand, capable of testing six cells simultaneously, was used for long-term corrosion testing. In-situ tests took place in 5 cm2 active area fuel cells with cathode humidification. Using data from test cells containing graphite monopolar plates as a baseline, two composite formulations, were able to produce power at 66-79% of the baseline power. Power output from one cell remained in this range for over 200 hours, while the other sample experienced surface oxidation and eventually failed. With improvements in part conductivity coming from conductive polymers, this manufacturing technique holds the promise of producing monopolar and bipolar plates that could eventually be scaled up for use in fuel cell stacks. / Master of Science

Dans les milieux astrophysiques explosifs tels que les novae ou les sursauts X, la densité d'hydrogène et la température sont suffisamment grandes pour que le temps entre deux réactions impliquant un proton soit plus court que le temps de vie de certains ions radioactifs. La connaissance de la section efficace des réactions de capture d’un proton par un ion radioactif est un des ingrédients important permettant la modélisation de tels milieux. Dans ce travail, un nouveau dispositif expérimental permettant d'étudier la force de résonance de réactions (p,gamma) en cinématique inverse est présenté. Ce dispositif, baptisé ARES (Astrophysical REcoil Separator), a été d’abord caractérisé à l'aide de l'étude de la réaction 19F(p,gamma)20Ne et plus particulièrement de la mesure de la force de la résonance bien connue à 635 keV au dessus du seuil 19F+p. De plus, la simulation de cette expérience est en accord avec les mesures effectuées. Une première mesure de force de résonance d'une réaction impliquant un faisceau d'ions radioactifs est ensuite présentée. Il s'agit de la réaction 19Ne(p,gamma)20Na et plus particulièrement de la résonance à 448 keV au dessus du seuil 19Ne+p. Une limite supérieure de 15.2 meV avec un niveau de confiance de 90% est obtenue. Cette limite supérieure améliore légèrement les résultats de mesures antérieures. / In explosive astrophysical environments such as novae or X-ray bursts, the temperature and the hydrogen density are so large that the time between two reactions involving protons is smaller than the live time of radioactive ions. The cross section of such reactions is an important ingredient of the modeling of such environments. In this work, a new experimental device, allowing the study of resonance strength of (p,gamma) reactions, is presented. This setup, called ARES (Astrophysical REcoil Separator), is first characterized using the study of the well known reaction, 19F(p,gamma)20Ne and more precisely the measurement of the resonance strength of the 635 keV level above the 19F+p threshold. The simulation of this experiment is found in good agreement with the measurement. Then the first resonance strength measurement of a reaction involving radioactive ions beams is presented, i.e. the resonance strength of the 448 keV level above the 19Ne+p threshold in the 19Ne(p,gamma)20Na reaction. An upper limit of 15.2 meV with a confidence level of 90% is obtained. This upper limit improves slightly the results of previous measurements.

Hydrodynamic vortex separators (HDVSs) are used in wastewater treatment to separate solids from wastewater. The aim of this research is to devise a CFD-based methodology that optimises their performance through modification of their design. A validation study is performed to assess whether OpenFOAM can be used to reliably model the flow of water in an HDVS. The results of the simulations are compared with experimental readings, showing a good fit when the appropriate boundary layer height and turbulence model are used. The continuous adjoint method is employed to derive the adjoint equations, associated with the drift flux equations used to model the flow of wastewater. They are specialised to the typical boundary conditions of ducted flows and are coded using OpenFOAM. An optimal design is found for boundary conditions, corresponding to typical values used in practice, and is shown to improve the performance of a simplified initial design by 40%. This optimal design is subsequently subjected to a different hydraulic loading rate and dispersed-phase volume fraction at the inlet, to assess the performance variation in these circumstances. Though the optimal design removes all the solids when the dispersed-phase fraction is reduced at the inlet, initial results suggest that the design is sensitive to hydraulic loading rate and further tests are recommended before drawing more explicit conclusions. This is the first time the adjoint drift flux equations have been derived. It is also the first time they have been coded and applied to an HDVS to optimise its performance. The methodology developed in this thesis could be applied to any device that separates solids from liquid or two immiscible liquids, in order to optimise its performance.

ABSTRACT This thesis contains solution of issue Effect of season to condition Holstein cattle breed in period from December 2013 to December 2014 in BONAGRO, a. s. in Šlapanice city in herd about 80 dairy cows in the first stage of lactation. Experiments were made periodically on the first week of month, overall twelve times per a year. Whole thesis is based on subjective evaluation of body condition of cows. I statistically demonstrated effect of season to condition of cows. I also showed that season affected feed factions. I subdued these factions to special sieve analysis (Penn State Separator). Furthermore, I found statistically conclusive effect of season to residual amount of washed excrements, which I subdued to primary analysis. Feed and excrement analysis place together with evaluation of body condition. At the same time, I measured temperature inside the stable and compared it with temperature in surroundings of Šlapanice. In the end, I made an analysis of milk in university laboratory, which were compared with results of control of heredity, regularly made on the farm. All results are shown in this thesis and are complemented by graphs, tables, analysis and photos.