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1
Liu, Chi-hong, and 廖志航. "Base friction modelling of discontinuous rock masses." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B42577123.
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Santoso, Agus Mathematics & Statistics Faculty of Science UNSW. "Evolution of climate anomalies and variability of Southern Ocean water masses on interannual to centennial time scales." Awarded by:University of New South Wales. School of Mathematics and Statistics, 2005. http://handle.unsw.edu.au/1959.4/33355.
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In this study the natural variability of Southern Ocean water masses on interannual to centennial time scales is investigated using a long-term integration of the Commonwealth Scientic and Industrial Research Organisation (CSIRO) coupled climate model. We focus our attention on analysing the variability of Antarctic IntermediateWater (AAIW), Circumpolar DeepWater (CDW), and Antarctic Bottom Water (AABW). We present an analysis of the dominant modes of temperature and salinity (T - S) variability within these water masses. Climate signals are detected and analysed as they get transmitted into the interior from the water mass formation regions. Eastward propagating wavenumber-1, -2, and -3 signals are identied using a complex empirical orthogonal function (CEOF) analysis along the core of the AAIW layer. Variability in air-sea heat uxes and ice meltwater rates are shown by heat and salt budget analyses to control variability of Antarctic Surface Water where density surfaces associated with AAIW outcrop. The dominant mode in the CDW layer is found to exhibit an interbasin-scale of variability originating from the North Atlantic, and propagating southward into the Southern Ocean. Salinity dipole anomalies appear to propagate around the Atlantic meridional overturning circulation with the strengthening and weakening of North Atlantic Deep Water formation. In the AABW layer, T - S anomalies are shown to originate from the southwestern Weddell Sea, driven by salinity variations and convective overturning in the region. It is also demonstrated that the model exhibits spatial patterns of T - S variability for the most part consistent with limited observational record in the Southern Hemisphere. However, some observations of decadal T - S changes are found to be beyond that seen in the model in its unperturbed state. We further assess sea surface temperature (SST) variability modes in the Indian Ocean on interannual time scales in the CSIRO model and in reanalysis data. The emergence of a meridional SST dipole during years of southwest Western Australian rainfall extremes is shown to be connected to a large-scale mode of Indian Ocean climate variability. The evolution of the dipole is controlled by variations in atmospheric circulation driving anomalous latent heat uxes with wind-driven ocean transport moderating the impact of evaporation and setting the conditions favourable for the next generation phase of an opposite dipole.
3
Hakami, Amir. "Direct sensitivity analysis in air quality models." Diss., Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04082004-180202/unrestricted/hakami%5Famir%5F200312%5Fphd.pdf.
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Khan, Maudood Naeem. "Development and application of an adaptive grid air quality model." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/20824.
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夏激揚 and Jiyang Xia. "Numerical study on wind field and air pollutant dispersion in urban street canopies." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31242509.
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Tsui, Ka-cheung, and 徐家祥. "Neighborhood ventilation of a building cluster by combined forces." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B42182128.
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Chung, Nga-hang, and 鍾雅行. "Large-eddy simulation of transport of inert and chemically reactive pollutants over 2D idealized street canyons." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47849903.
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In view of the worsening air quality in the world, more concerns are focused on the
environment. This thesis uses the technique of CFD and develops the computer model
to investigate the wind and pollutant transport, as well as the chemistry of reactive
pollutants in idealized two-dimensional (2D) street canyons.
Three scientific questions are raised in this thesis. The first task is to find out the po-
sition with the most favorable pollutant removal along the ground level over 2D idealized
street canyon of different building-height-to-street-width (aspect) ratios (ARs). The di-
mensionless parameter, C, represents the pollutant removal performance. In the isolated
roughness regime, the two local maximum C locate at the reattachment point and the
windward corner. In the wake interference regime, C is peaked on the windward side. The
number of vertically aligned recirculations depends on the street depth in the skimming
flow regime. The sizes of the secondary recirculation upstream and downstream deter-
mine how the maximum C shifts from the street centre. After identifying the position of
peaked pollutant removal rate at the ground level, the emission source should be placed
with the highest constant C in order to remove the pollutants upward more quickly to
safeguard the street-level air quality.
After understanding the best pollutant removal in the street canyon of different ARs,
the second task is to find out what AR is the most favorable for the ventilation and
pollutant removal across the roof level. The three parameters, namely friction factor,
air exchange rate (ACH) and pollutant exchange rate (PCH), are introduced to quantify
the pressure difference to sustain the mean flow, the ventilation and pollutant removal,
respectively. The turbulence contributes more than 70% to the total ACH and PCH in
all the three flow regimes. By increasing the atmospheric turbulence in building geometry
as well as the surface roughness, the ventilation and pollutant removal performance can
be improved. The linear relation between the friction factor and ACH demonstrates the
larger resistance that in turn promotes the air exchange over the roof level.
The physical dispersion is studied; however atmospheric pollutants are seldom in-
ert but chemically reactive instead. The last task is to include the three common air
pollutants, NO, NO2 and O3, in the simple NOx ?O3 mechanism in terms of the photo-
stationary state and reaction rates. The Damkohler numbers of NO and O3, DaNO and
DaO3, are parameterized by the concentrations of the sources NO and O3. The normalized
mean and fluctuation NO, NO2 and O3 are separately considered. The integrated pho-
tostationary state (PSS) in the first canyon increases with DaO3 under the same DaNO.
The integrated PSS of the second to the twelveth street canyons are compared with each
case, the monotonic increase in the PSS from the second to twelveth canyon is perceived
in DaNO/DaO3 1, 0.03, 0.02, 0.001 and 0.000333. Further decreases the DaNO/DaO3 to
0.000143, 0.000125, 0.000118, 0.000111 and 0.0001, the PSS is found to be non-linear and
the trough appears in the fourth and fifth canyons.published_or_final_version
Mechanical Engineering
Master
Master of Philosophy
8
Leung, Ka-kit Pieta, and 梁家杰. "On the study of ventilation and pollutant removal over idealized two-dimensional urban street canyons." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B48521863.
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In the last century, there has been a rapid growth and development in economy and modern technology around the world. This phenomenon helped improving wealth and living standard but also brought pollutions to the society and the environment. Among various kinds of pollution, air pollution takes a larger proportion. Therefore, there is increasing concern about the ventilation and pollution removal behavior in the urban environment.
Among different academic studies performed, the use of computational fluid dynamics (CFD) had become more popular. Since wind tunnel experiments serve as validations for CFD results, this thesis developed the technique required for wind tunnels experiments and to investigate the pollutant removal related to urban geometry, as well as the technique for gas sampling to examine the distribution of pollutants in urban boundary layer over idealized two-dimensional (2D) street canyons.
Three specific tasks are archived to accomplish the above objectives. The first task was to extend the wind tunnel in the Department of Mechanical Engineering, the University of Hong Kong. An extension duct was designed to increase the length of the test section in which the reduced-scale model could be installed. The dimensions of the test section were specified according to the required length for fully developed flow inside the test section, the environment in the laboratory and the original wind tunnel conditions. The extension duct was then constructed and mounted, with the wind profile inside the test section obtained afterwards.
After construction of the extended test section for experimental purposes, the second task was to examine the pollutant transport behaviors from the ground level of idealized 2D urban street canyons to the urban atmospheric boundary layer (ABL) using both laboratory wind tunnel measurements and CFD. Movable rectangular aluminum blocks were placed in the wind tunnel in cross-flow to construct street canyons of different building-height-to-street-width (aspect) ratios. Wetted filter papers were applied on the surface of the blocks inside the street region, modeling the source of pollutant emission inside the street canyons. The wind tunnel and CFD results complemented each other to elucidate the pollutant removal mechanism that is in line with other results available in literature. From the experimental results obtained, scaling effect was observed in the mass transfer behaviors even the flows had fulfilled kinematic similarity. A new indicator, the scaled overall pollutant removal coefficient, was formulated for the comparison of pollutant removal performance. The improved agreement in the comparison with the CFD results showed that the scaled overall pollutant removal coefficient could be used to account for the scaling effects occurred in laboratory experiments at finite Reynolds number (〖10〗^(3 ) to 〖10〗^(5 ) in this study) for comparison of pollutant removal performance.
The behavior of pollutants inside the street canyons was studied; however, the pollutant concentration inside a street could be affected by the pollutant source in another street, even there were several streets away from it. The pollutant escaped from the source street could act as air entrainment into other streets, affecting the air quality. The concentration profile correlated to the street geometry was thus studied. The last task of this dissertation was to study the effect of urban geometry on the concentration profile of the urban ABL by means of gas dispersion experiments. Experiments were carried out in the wind tunnels of the Department of Mechanical Engineering and Department of Civil Engineering with different sets of experimental models used. A special gas emission source was constructed in order to simulate the linear source due to busy traffic in the street regions. The required gas sampling techniques were also studied throughout the measurement. Trial experiments were carried out and preliminary results had been obtained. Furthermore, the pollutant concentration profiles downstream from a linear pollutant source in an idealized 2D street canyon were also measured. Throughout the experiments, different designs of line source were tested and factors affecting the experimental results were considered. One of the line source designs was adopted and the pollutant concentrations in street canyons of different aspect ratios were observed. The concentration decreases rapidly with increasing distance from the roof but then increases to steady value. The average pollutant concentration over the concentration profile was different at different aspect ratios. It is believed that its performance depends on the pollutant removal behavior from street regions.published_or_final_version
Mechanical Engineering
Master
Master of Philosophy
9
Wong, Ching-chi, and 黃精治. "Flow and pollutant dispersion over idealized urban street canyons using large-eddy simulation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/206698.
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Flows and pollutant dispersion over flat rural terrain have been investigated for decades. However, our understanding of their behaviours over urban areas is rather limited. Most cases have either focused on street level or in the roughness sub-layer (RSL) of urban boundary layer (UBL). Whereas, only a handful of studies have looked into the coupling between street-level and UBL-core dynamics, and their effects on pollutant dispersion.
In this thesis, computational fluid dynamics (CFD) is employed to examine the flows and pollutant transport in and over urban roughness. Idealised two-dimensional (2D) street canyons are used as the basic units fabricating hypothetical urban surfaces. A ground-level passive and chemically inert pollutant source is applied to simulate the flows and pollutant dispersion over rough surfaces in isothermal condition. Large-eddy simulation (LES) with the one-equation subgrid-scale model is used to solve explicitly the broad range of scales in turbulent flows. Arrays of idealized street canyons of both uniform and non-uniform building height are used to formulate a unified theory for the flows and pollutant dispersion over urban areas of different morphology. The geometry of roughness elements is controlled by the building-height-to-street-width (aspect) ratio (0.083 ≤ AR ≤ 2) and/or the building height variability (BHV = 0.2, 0.4 and 0.6), in which the characteristic regimes of skimming flow, wake-interference and isolated roughness are covered.
A detailed analysis on the roof-level turbulence structure reveals parcels of low-speed air masses in the streamwise flows and narrow high-speed down-drafts in the urban canopy layer, signifying the momentum entrainment into the street canyons. The decelerating streamwise flows in turn initiate up-drafts carrying pollutants away from the street canyons, illustrating the basic pollutant removal mechanism in 2D street canyons. Turbulent transport processes, in the form of ejection and sweep, are the key events governing the exchanges of air and pollutant of street canyon. Air exchange rate (ACH) along the roof level is dominated by turbulent transport, in particular over narrow street canyons.
The LES results show that both the turbulence level and ACH increase with increasing aerodynamic resistance defined in term of the Fanning friction factor. At the same AR, BHV greatly increases the friction factor and the ACH in dense built areas (AR ≤ 0.25). The turbulence intensity is peaked on the windward side of street canyons that does not overlap with the maximum velocity gradient near the leeward building corners, suggesting the importance of background turbulence in street-level ventilation. Over the building roughness, pollutant plume dispersion after the ground-level area source in cross flows resumes the self-similar Gaussian shape in the vertical direction in which the vertical plume coverage is proportional to the square root of downwind distance in the streamwise direction. Moreover, the vertical dispersion coefficient is proportional to the one-fourth power of friction factor over idealised street canyons. Conclusively, friction factor can be used to parametrise ventilation and pollutant dispersion over urban areas.published_or_final_version
Mechanical Engineering
Doctoral
Doctor of Philosophy
10
Yan, Tsz-leung, and 甄子良. "Spatio-temporal modeling and forecasting of air quality data." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/197498.
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Respirable Suspended Particulate (RSP) time series data sampled in an air quality monitoring network are found strongly correlated and they are varying in highly similar patterns. This study provides a methodology for spatio-temporal modeling and forecasting of multiple RSP time series, in which the dynamic spatial correlations amongst the series can be effectively utilized.
The efficacy of the Spatio-Temporal Dynamic Harmonic Regression (STDHR) model is demonstrated. Based on the decomposition of the observed time series into the trend and periodic components, the model is capable of making forecast of RSP data series that exhibit variation patterns during air pollution episodes and typhoons with dynamic weather conditions. It is also capable to produce spatial predictions of RSP time series up to three unobserved sites.
The Noise-variance-ratio (NVR) form of the multivariate recursive algorithm ((M2) algorithm) that derived by the author can greatly facilitate its practical application in both multivariate and univariate time series analysis. The (M2) algorithm allows the spatial correlations to be specified at parametric levels. The state-space (SS) model formulation can flexibly accommodate the existing inter or intra (auto) correlations amongst the parameters of the data series.
Applications of the variance intervention (VI) are exploited and illustrated with a real life case study which involves forecasting of RSP data series during an air pollution episode. This illustrates that time series with abrupt changes can be predicted by automatic implementation of the VI approach.
The present study also extended the anisotropic Matern model to estimate the dynamic spatial correlation structure of the air quality data by using mean wind speed and prevailing wind direction in defining the spatial anisotropy. The Anisotropic Matern model by Mean Wind Speed and Prevailing Wind Direction (AMMP) model that devised by the author can avoid huge computational burden in estimating variogram at every variation of the underlying spatial structure.
Finally, the findings of this dissertation have laid the foundation for further research on multiple time series analysis and estimation of dynamic spatial structure.published_or_final_version
Geography
Doctoral
Doctor of Philosophy
11
Marks, Marguerite Colasurdo. "Incorporating Chemical Activity and Relative Humidity Effects in Regional Air Quality Modeling of Organic Aerosol Formation." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1511.
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Atmospheric particulate matter is known to have significant effects on human health, visibility, and global climate. The magnitudes of these effects, however, depend in complex ways on chemical composition, relative humidity, temperature, phase state, and other parameters. Current regional air quality models such as CMAQ (Community Multiscale Air Quality model) ignore many of these considerations, and consider that the formation of secondary organic aerosol (SOA) can be calculated by assuming thermodynamic ideality in the organic particulate matter (OPM) phase as well as negligible uptake of water into the OPM phase. Theoretical predictions and model simulations considering non-ideality and water uptake show that the standard model assumptions can lead to large errors in predicted SOA mass, and that the magnitude of these errors is sensitive to the composition of the OPM phase.
The SOA module in CMAQ v4.7.1 has been revised in this work to allow consideration of the effects of both non-ideality and water uptake. First, a reasonable specific surrogate structure was assigned to each of the lumped products assumed to be produced by reaction of the different precursor hydrocarbons considered in CMAQ (e.g., isoprene, benzene, and toluene). Second, the CMAQ code was modified to allow iterative calculation (at each point in space and time) of the gas/particle partitioning coefficient for each of the SOA-forming products and for water. Third, model simulations were performed for the Eastern US at a resolution of 36-km x 36-km for late summer 2006, under a range of relative humidity conditions.
When compared with an appropriate base case, the modified code produced increases in SOA ranging from 0.17 to 0.51 micrograms per cubic meter. The average change was 0.30 micrograms per cubic meter, corresponding to a 37% increase in SOA formation. Incorporation of phase separation effects would likely lead to further increases in predicted SOA levels.
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Li, Xianxiang, and 李顯祥. "Large-eddy simulation of wind flow and air pollutant transport inside urban street canyons of different aspect ratios." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40687326.
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Cheng, Wai-chi, and 鄭偉智. "Wind and pollutant removal of urban street canyons under different thermal stratification by RANS and LES models." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B46289653.
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廖俊豪 and Chun-ho Liu. "Numerical modelling of atmospheric boundary layer with application to air pollutant dispersion." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31239018.
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黃潤棠 and Yun-tong Anton Wong. "Computational study of wind flow and pollution dispersion in an urban street canyon of various geometries." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31226905.
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Yang, Jing Yi. "An improved algorithm for data filtering based on variation for short term air pollution prediction in Macau." Thesis, University of Macau, 2012. http://umaclib3.umac.mo/record=b2592957.
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Zhao, Chun. "Impact of convection and lightning on the tropospheric chemistry composition over North America and air quality studies over East Asia." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28114.
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Thesis (M. S.)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2009.Committee Chair: Yuhang Wang; Committee Member: Armistead Russell; Committee Member: Athanasios Nenes; Committee Member: Greg Huey; Committee Member: Judith Curry.
18
Feng, Ming-Fa. "Fault diagnosis and prediction in reciprocating air compressors by quantifying operating parameters." Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/39786.
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This research introduces a new method of diagnosing the internal condition of a reciprocating air compressor. Using only measured load torques and shaft dynamics, pressures, temperatures, flow rates, leakages, and heat transfer conditions are quantified to within 5%.
The load torque acting on the rotor of the machine is shown to be a function of the dynamics (instantaneous position, velocity, and acceleration) of the driving shaft, the kinematic construction, and the internal condition of the machine. If the load torque, the kinematic construction of the machine, and the dynamics of the rotor are known, then the condition of the machine can be assessed.
A theoretical model is developed to describe the physical behavior of the slider-crank mechanism and the shaft system. Solution techniques, which are based on the machine construction, crankshaft dynamics, and load torque measurements, are presented to determine the machine parameters. A personal computer based system used to measure the quantities necessary to solve for the machine parameters and the quantities used to compare with calculations is also documented.
The solution algorithm for multi-stage compressors is verified by decoupling the load torque contributed by each cylinder. Pressure data for a four-stage two-cylinder high pressure air compressor (HPAC) is used. Also, the mathematical model is proven feasible by using measured angular velocity of the crankshaft and direct measurements of the load torque of a single stage, single cylinder air compressor to solve for the machine parameters.
With this unintrusive and nondestructive method of quantifying the operating parameters, the cylinder pressures, operating temperatures, heat transfer conditions, leakage, and power consumption of a reciprocating air compressor can be evaluated.Ph. D.
19
So, Shuk-pan Ellen, and 蘇淑彬. "Large eddy simulations of wind flow and pollution dispersion in an urban street canyon." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B29332710.
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Lai, Kwong-kei Murphy, and 賴廣麒. "Two-dimensional computational study on indoor/outdoor air quality relationship in urban buildings." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38725149.
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Bhave, Prakash Viththal Seinfeld John H. "Air pollution at the single-particle level : integrating atmospheric measurements with mathematical models /." Diss., Pasadena, Calif. : California Institute of Technology, 2003. http://resolver.caltech.edu/CaltechETD:etd-05252003-091827.
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Kaharabata, Samuel K. "Non-disturbing methods of estimating trace gas emissions from agricultural and forest sources." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35903.
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Two approaches, one using an atmospheric diffusion model and the other an atmospheric tracer, were used to predict the source strength of trace gases from observations of the downwind concentration field. Both approaches do not disturb the prevailing environmental and physical conditions nor the existing biogenic processes. An analytical solution to the advection-diffusion equation was used to back-calculate the source strength from the downwind concentration measurements of (i) single and multipoint (4 and 16 points) trace gas (sulphur hexafluoride (SF6) and methane (CH4)) release experiments conducted over microplots over an open field, and (ii) single point source SF6 release experiments conducted over a forested terrain. Best predictions of the source strength (to within +/-20%) were obtained from concentration observations made along the centreline of the diffusing plumes with the predictions improving when observations at the mean plume height were used. The diffusion model was then used to compute footprint estimates for neutral and unstable conditions, for tower and aircraft based observation platforms above the forest. They showed spatially constrained footprints in the surface layer, due to effective vertical coupling, so that observations from towers and low flying aircraft must be expected to be very site specific, and scaling up to larger areas will have to be done with careful consideration of surface mosaics. Above-canopy sampling of trace gases to determine volatile organic compound emissions were then interpreted in terms of footprint considerations. This was accomplished by defining the upwind canopy areas effectively sampled under the given wind and stability conditions. The analysis demonstrated, for example, that the variability observed in measured isoprene fluxes could be accounted for by varying numbers of randomly distributed clumps of emitter species within a varying footprint. It suggested that heterogeneity of the forest canopy, in terSulphur hexafluoride was also used as an atmospheric tracer in order to estimate CH4 emissions from manure slurry and cattle housed in barns and feedlots. (Abstract shortened by UMI.)
23
Todd, Richard Shannon. "A theoretical and experimental study of a rapid pressure swing adsorption system for air separation." Monash University, Dept. of Chemical Engineering, 2003. http://arrow.monash.edu.au/hdl/1959.1/5533.
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Tong, Yun-on, and 唐潤安. "Statistical analysis of air pollutants and numerical modeling of reactive pollutant dispersion within street canyon." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46607031.
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李永智 and Wing-chi Steven Lee. "Analytical study of wind flow and pollutant dispersion past hills." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31224672.
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Hang, Jian, and 杭建. "Wind conditions and urban ventilation in idealized city models." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B42841471.
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Kinsman, Roger Gordon. "Outlet discharge coefficients of ventilation ducts." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59271.
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Discharge coefficients are an important parameter in the prediction of the air displacement performance of ventilation outlets and in the design of ventilation ducts.Discharge coefficients of a wooden ventilation duct 8.54 metres in length and of a constant 0.17 m$ sp2$ cross sectional area were measured. Four different outlet shapes and 3 aperture ratios of each shape were tested. A split plot experimental design was used to evaluate the effect of outlet shape, outlet size, and distance from the fan on discharge coefficient. The relationship between duct performance characteristics and discharge coefficient was examined. A mathematical equation to predict the discharge coefficient was developed and tested.
Discharge coefficient values measured ranged from 0.19 to 1.25 depending on the aperture ratio and distance from the fan. Outlet shape had no significant effect. The apparent effects of aperture ratio and size are due to the effects of head ratio. The equation predicting the discharge coefficient had a maximum error of 5 percent for the aperture ratios of 0.5 and 1.0, and 15 percent at an aperture ratio of 1.5.
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El, Moueddeb Khaled. "Principles of energy and momentum conservation to analyze and model air flow for perforated ventilation ducts." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=42024.
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A theoretical model was developed to predict the air distribution pattern and thus to design perforated ventilation ducts equipped with a fan. The analysis of the air distribution pattern of such systems requires accurate measurement procedures. Several experimental methods were tested and compared. Accordingly, the piezometric flush taps and thermo-anemometer were selected to measure respectively the duct air pressure and the outlet air flow.Based on the equations of energy and momentum conservation, a model was formulated to predict the air flow performance of perforated ventilation ducts and to evaluate the outlet discharge angle and the duct regain coefficients without evaluating frictional losses. The basic assumptions of the model were validated by experimentally proving the equivalence of the friction losses expressed in the 2 cited equations. When compared to experimental results measured from four wooden perforated ventilation ducts with aperture ratios of 0.5, 1.0, 1.5, and 2.0, the model predicted the outlet air flow along the full length of perforated duct operated under turbulent flow conditions with a maximum error of 9%. The regain coefficient and the energy correction factor were equal to one, and the value of the discharge coefficient remained constant at 0.65, along the full length of the perforated duct. The outlet air jet discharge angle varied along the entire duct length, and was not influenced by friction losses for turbulent flow.
Assuming a common effective outlet area, the model was extended to match the performance of the fan and the perforated duct and to determine their balance operating point.
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MacKinnon, Ian R. (Ian Roderick) 1964. "Air distribution from ventilation ducts." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59655.
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A wooden, perforated, uniform cross-section duct was examined to determine the optimum levels of aperture ratio and fan speed with respect to uniformity of discharge. The optimum aperture ratio for the 8.54 m long duct was 1.0 with a uniformity coefficient of 90.28%. The fan speed had little effect on the uniformity of discharge. The friction factor was experimentally determined to be 0.048 for a non-perforated duct and this value was assumed to be the same for a perforated duct of similar construction. A kinetic energy correction factor was used to analyze the flow in the duct. Values for this correction factor were determined from experimental data. Values of the coefficient of discharge and the total duct energy were calculated. A mathematical model was proposed based on the conservation of momentum and the Bernoulli's equation. The model responded favourably and predicted the duct velocity nearly perfectly and slightly underestimated the total duct energy.
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Kumar, Niraj. "A genetic algorithm based approach for air cargo loading problem." Thesis, Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B38576818.
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葉啓明 and Kai-ming Ip. "Dynamic response of a cooling and dehumidifying coil to variations in air flow rate." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31215361.
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Yan, Ka-lok, and 忻嘉樂. "Time series regression modelling of air quality data in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31252990.
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Dombek, Priscilla Emily 1961. "IMPROVING THE CONVERSION OF THE SULFUR DIOXIDE - LIME REACTION BY USING ADDITIVES." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/291523.
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Wells, Judith R. (Judith Roberta). "A laboratory study of localized boundary mixing in a rotating stratified fluid." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/58062.
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Thesis (Ph. D.)--Joint Program in Physical Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, and the Woods Hole Oceanographic Institution), 2003.Includes bibliographical references (p. 145-148).
Oceanic observations indicate that abyssal mixing is localized in regions of rough topography. How locally mixed fluid interacts with the ambient fluid is an open question. Laboratory experiments explore the interaction of mechanically induced boundary mixing and an interior body of linearly stratified rotating fluid. Turbulence is generated by a vertically oscillating horizontal bar, located at middepth along the tank wall. The turbulence forms a region of mixed fluid which quickly reaches a steady state height and collapses into the interior. The mixed layer thickness ... is independent of the Coriolis frequency f. N is the buoyancy frequency, co is the bar frequency, and the constant, Y=1 cm, is empirically determined by bar mechanics. In initial experiments, the bar is exposed on three sides. Mixed fluid intrudes directly into the interior as a radial front of uniform height, rather than as a boundary current. Mixed fluid volume grows linearly with time ... The circulation patterns suggest a model of unmixed fluid being laterally entrained with velocity, e Nhm, into the sides of a turbulent zone with height hm and width Lf ... where Lf is an equilibrium scale associated with rotational control of bar-generated turbulence. In accord with the model, outflux is constant, independent of stratification and restricted by rotation ... Later experiments investigate the role of lateral entrainment by confining the sides of the mixing bar between two walls, forming a channel open to the basin at one end. A small percentage of exported fluid enters a boundary current, but the bulk forms a cyclonic circulation in front of the bar. As the recirculation region expands to fill the channel, it restricts horizontal entrainment into the turbulent zone. The flux of mixed fluid decays with time.
(cont.) ... The production of mixed fluid depends on the size of the mixing zone as well as on the balance between turbulence, rotation and stratification. As horizontal entrainment is shut down, longterm production of mixed fluid may be determined through much weaker vertical entrainment. Ultimately, the export of mixed fluid from the channel is restricted to the weak boundary current.
by Judith R. Wells.
Ph.D.
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Yuen, Chi-king, and 阮志敬. "Feasibility of using neural network for air dispersion modelling." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1995. http://hub.hku.hk/bib/B31253325.
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Chichka, David F. "Cruise-dash optimization applied to an air-breathing missile." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/90923.
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The method of singular perturbations is applied to the determination of the optimal range-fuel-time trajectory for an air-breathing missile. This method is shown to lead to the reduced-order "cruise-dash" model, and this model is used in the optimization study. Earlier work in this area is extended by the inclusion of two not heretofore considered limits on the dynamical system.
The results of the earlier work are shown to hold throughout much of the velocity regime in which the missile operates, but operation in the very high and very low velocity ranges is shown to be sharply curtailed, with the optimal operating points being changed drastically in some cases. Also, the effect of the non-zero minimum admissible throttle setting and the resultant throttle-chattering on the solution of the control problem is examined in some detail.M.S.
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Yu, Peng, and 于朋. "Air pollution and respiratory disease incidence of Guangzhou: a study of spatial interpolation methodsusing GIS, 2003-2004." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41633799.
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Chapman, Peter Stuart. "The outdoor horizontal and vertical variations of respirable suspendedparticulate concentrations within a densely urban environment in HongKong: application of a box and plumedispersion model (airGIS/OSPM)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47869847.
Full textAbstract:
Background
There have been many multicity studies assessing health effects of the
population’s exposure to PM10. They assume that there is homogeneous exposure to PM10
and the monitoring locations are representative of the population’s exposure. In a
densely urban environment, like Hong Kong, street canyons are common and could alter
PM10 exposure. The horizontal and vertical dispersion of PM10 in the urban environment
is complex due to the interactions of street geometric, metrological and pollution source
conditions. The airGIS/OSPM is a box and plume mathematical model which was
designed to model this complex dispersion of PM10.
Objectives
This study aims to utilize the airGIS/OSPM to assess how the health impact is
affected by the misclassifications of within city air pollution exposure. This helps
assessing the feasibility of using the airGIS/OSPM in health studies.
Methods
The airGIS/OSPM was used for an urban area of Hong Kong, in the north west of
Kowloon Peninsular for a period from 1998 to spring 2011. PM10 concentration’s were
estimated at field measurement points, an EPD roadside monitoring site, and subjects in a
subset of the elderly healthcare center cohort and for all building addresses in the
modeled area.
The airGIS/OSPM was validated by conducting a PM10 measurement campaign
over the winter of 2010 to 2011. Also validation was conducted using the measurements
of the Mong Kok EPD roadside monitoring station.
A pilot study using the time stratified case-crossover analysis was conducted to
explore the effects of using the airGIS/OSPM to express the subjects’ short-term outdoor
residential exposure to PM10 on all cause mortality.
AirGIS/OSPM PM10 estimates were compared with ambient concentrations
obtained from the EPD monitoring network. The population mean exposure was
calculated using the airGIS/OSPM estimated PM10 concentration at all building address
points from 2007 to 2009 at the ground level and at middle building height level.
The airGIS/OSPM estimate was used to identify spatial variation of PM10 within
the study area.
Results
The airGIS/OSPM estimated well the measured PM10 concentration from the field
measurement campaign and the EPD Mong Kok station.
The airGIS/OSPM estimate and the ambient measure for EHC subject exposure
both found an odds ratio for all cause mortality there was no difference from unity
between case and control times.
The airGIS/OSPM derived mean PM10 concentration at the middle height of each
building was 54.8μg/m3 while that at the all EPD was 54.4μg/m3. At ground level the
airGIS/OSPM PM10 estimate was 58.35μg/m3 while that at the EPD was 54.41μg/m3.
Conclusion
The misclassification of PM10 was negligible at the middle of buildings, but for
people regularly working in ground level microenvironments are often exposed to PM10
concentrations that are higher than those measured at EPD monitors.
It is feasible to use the airGIS/OSPM model to estimate PM10 exposure. The
small spatial variation in exposure means the airGIS/OSPM may not be appropriate in
assessing the short-term PM10 exposure, but due to the larger effect size it might be
important in long-term exposure assessment.published_or_final_version
Community Medicine
Master
Master of Philosophy
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Garrett, Joseph Lee. "A comparison of flux-splitting algorithms for the Euler equations with equilibrium air chemistry." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/44636.
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The use of flux-splitting techniques on the Euler equations is considered for high Mach number, high temperature flows in which the fluid is assumed to be inviscid air in equilibrium. Three different versions of real gas extensions to the Stegerâ Warming and Van Leer flux-vector splitting, and four different versions of real gas extensions to the Roe flux-difference splitting, are compared with regard to general applicability and ease of implementation in existing perfect gas g algorithms. Test computations are performed for the M = 5, high temperature flow over a 10-degree wedge and the M = 24.5 flow over a blunt body. Although there were minor differences between the computed results for the three types of flux-splitting algorithms considered, little variation is observed between different versions of the same algorithm.
Master of Science
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Cheung, Ching, and 張靜. "Effect of heat flux on wind flow and pollutant dispersion in an urban street canyon." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37742498.
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Fu, Yan. "Modelling of ducted ventilation system in agricultural structures." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60519.
Full textAbstract:
Air distribution ducts are used in the environmental control of livestock and poultry building as well as the conditioning of most agricultural produce.In order to simplify the approach to the design of ventilation ducts, a mathematical equation has been derived to describe the average air velocity of a duct.
The primary objective of the research work was to test goodness of fit of an equation describing the average air velocity of perforated ventilation ducts, under balanced as well as unbalanced air distribution: $V = H sb{o}{X over L} + (V sb{L}-H sb{o}) {X sp2 over L sp2}$.
This equation was successfully tested using data measured from 14 ducts of constant cross-sectional area, built of wood or polyethylene with outlets of various shapes and aperture ratios. Results indicated that aperture ratio and distance along the duct are the two most significant factors influencing the average duct air velocity values, but material and outlet shape had little effect.
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Sanyal, Anuradha. "Large eddy simulation of syngas-air diffusion flames with artificial neural networks based chemical kinetics." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42785.
Full textAbstract:
In the present study syngas-air diffusion flames are simulated using LES with artificial neural network (ANN) based chemical kinetics modeling and the results are compared with previous direct numerical simulation (DNS) study, which exhibits significant extinction-reignition and forms a challenging problem for ANN. The objective is to obtain speed-up in chemistry computation while still having the accuracy of stiff ODE solver. The ANN methodology is used in two ways: 1) to compute the instantaneous source term in the linear eddy mixing (LEM) subgrid combustion model used within LES framework, i.e., laminar-ANN used within LEMLES framework (LANN-LEMLES), and 2) to compute the filtered source terms directly within the LES framework, i.e., turbulent-ANN used within LES (TANN-LES), which further dicreases the computational speed. A thermo-chemical database is generated from a standalone one-dimensional LEM simulation and used to train the LANN for species source terms on grid-size of Kolmogorov scale. To train the TANN coefficients the thermo-chemical database from the standalone LEM simulation is filtered over the LES grid-size and then used for training. To evaluate the performance of the TANN methodology, the low Re test case is simulated with direct integration for chemical kinetics modeling in LEM subgrid combustion model within the LES framework (DI-LEMLES), LANN-LEMLES andTANN-LES. The TANN is generated for a low range of Ret in order to simulate the specific test case. The conditional statistics and pdfs of key scalars and the temporal evolution of the temperature and scalar dissipation rates are compared with the data extracted from DNS. Results show that the TANN-LES methodology can capture the extinction-reignition physics with reasonable accuracy compared to the DNS. Another TANN is generated for a high range of Ret expected to simulate test cases with different Re and a range of grid resolutions. The flame structure and the scalar dissipation rate statistics are analyzed to investigate success of the same TANN in simulating a range of test cases. Results show that the TANN-LES using TANN generated fora large range of Ret is capable of capturing the extinction-reignition physics with a very little loss of accuracy compared to the TANN-LES using TANN generated for the specific test case. The speed-up obtained by TANN-LES is significant compared to DI-LEMLES and LANN-LEMLES.
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Snyder, Scott D. "A fundamental study of active noise control system design /." Title page, contents and abstract only, 1991. http://web4.library.adelaide.edu.au/theses/09PH/09phs675.pdf.
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Balachandran, Sivaraman. "The development, application and evaluation of advanced source apportionment methods." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50279.
Full textAbstract:
Ambient and indoor air pollution is a major cause of premature mortality, and has been associated with more than three million preventative deaths per year worldwide. Most of these health impacts are from the effects from fine particulate matter. It is suspected that PM2.5 health effects vary by composition, which depends on the mixture of pollutants emitted by sources. This has led to efforts to estimate relationships between sources of PM2.5 and health effects. The health effects of PM2.5 may be preferentially dependent on specific species; however, recent work has suggested that health impacts may actually be caused by the net effect of the mixture of pollutants which make up PM2.5. Recently, there have been efforts to use source impacts from source apportionment (SA) studies as a proxy for these multipollutant effects. Source impacts can be quantified using both receptor and chemical transport models (RMs and CTMs), and have both advantages and limitations for their use in health studies.
In this work, a technique is developed that reconciles differences between source apportionment (SA) models by ensemble-averaging source impacts results from several SA models. This method uses a two-step process to calculate the ensemble average. An initial ensemble average is used calculate new estimates of uncertainties for the individual SA methods that are used in the ensemble. Next, an updated ensemble average is calculated using the SA method uncertainties as weights. Finally, uncertainties of the ensemble average are calculated using propagation of errors that includes covariance terms. The ensemble technique is extended to include a Bayesian formulation of weights used in ensemble-averaging source impacts. In a Bayesian approach, probabilistic distributions of the parameters of interest are estimated using prior distributions, along with information from observed data.
Ensemble averaging results in updated estimates of source impacts with lower uncertainties than individual SA methods. Overall uncertainties for ensemble-averaged source impacts were ~45 - 74%. The Bayesian approach also captures the expected seasonal variation of biomass burning and secondary impacts. Sensitivity analysis found that using non-informative prior weighting performed better than using weighting based on method-derived uncertainties. The Bayesian-based source impacts for biomass burning correlate better with observed levoglucosan (R2=0.66) and water soluble potassium (R2=0.63) than source impacts estimated using more traditional methods, and more closely agreed with observed total mass. Power spectra of the time series of biomass burning source impacts suggest that profiles/factors associated with this source have the greatest variability across methods and locations.
A secondary focus of this work is to examine the impacts of biomass burning. First a field campaign was undertaken to measure emissions from prescribed fires. An emissions factor of 14±17 g PM2.5/kg fuel burned was determined. Water soluble organic carbon (WSOC) was highly correlated with potassium (K) (R2=.93) and levoglucosan (R2=0.98). Results using a biomass burning source profile derived from this work further indicate that source apportionment is sensitive to levels of potassium in biomass burning source profiles, underscoring the importance of quantifying local biomass burning source profiles. Second, the sensitivity of ambient PM2.5 to various fire and meteorological parameters in was examined using the method of principle components regression (PCR) to estimate sensitivity of PM2.5 to fire data and, observed and forecast meteorological parameters. PM2.5 showed significant sensitivity to PB, with a unit-based sensitivity of 3.2±1 µg m-3 PM2.5 per 1000 acres burned. PM2.5 had a negative sensitivity to dispersive parameters such as wind speed.
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Soares, Darrow P. "Curriculum in mathematics for air conditioning and refrigeration." CSUSB ScholarWorks, 1996. https://scholarworks.lib.csusb.edu/etd-project/1239.
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Peter, Justin R. "Numerical investigation of aerosol dynamics : evaluation of the Hamaker constant for environmental tobacco smoke." Thesis, Queensland University of Technology, 1996. https://eprints.qut.edu.au/36917/1/36917_Peter_1996.pdf.
Full textAbstract:
Human exposure to atmospheric pollutants (aerosols) depends on the nature and concentration of the pollutants, and also on the size distribution of the particulate phase of the aerosol. One such commonly encountered aerosol of significant physiological importance is Environmental Tobacco Smoke (ETS). Knowledge of the time evolution of combustion aerosols is necessary to understand the interactions which shape the aerosol size distribution, and thus lead to conclusions as to the health risk associated with exposure to ETS.
A systematic numerical investigation of the dynamics of aerosol coagulation with the inclusion of van der Waal's forces has been undertaken. Numerical results are compared with those obtained experimentally for the size distribution ofETS in the particle range, 10 nm < particle diameter < 1000 nm. These particles diameters lie in the Cunningham Slip-Flow region, between the free-molecule and continuum regions. The newly developed numerical method allows direct simulation to obtain the size distributions of aging aerosols of arbitrary diameter. Considering that other processes such as condensation and wall deposition are not considered, results obtained theoretically are in excellent agreement with those obtained experimentally.
The comparison of experimental and numerical results enables conclusions to be made as the value of the Hamaker constant for ETS. Although the Hamaker constant is only defined for a pure substance, the method allows an average value over all the constituents of ETS to be evaluated. This value can then be used as input for any further modelling ofETS.
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Powell, James Eckhardt. "Building a Multivariable Linear Regression Model of On-road Traffic for Creation of High Resolution Emission Inventories." PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3415.
Full textAbstract:
Emissions inventories are an important tool, often built by governments, and used to manage emissions. To build an inventory of urban CO2 emissions and other fossil fuel combustion products in the urban atmosphere, an inventory of on-road traffic is required. In particular, a high resolution inventory is necessary to capture the local characteristics of transport emissions. These emissions vary widely due to the local nature of the fleet, fuel, and roads.
Here we show a new model of ADT for the Portland, OR metropolitan region. The backbone is traffic counter recordings made by the Portland Bureau of Transportation at 7,767 sites over 21 years (1986-2006), augmented with PORTAL (The Portland Regional Transportation Archive Listing) freeway traffic count data. We constructed a regression model to fill in traffic network gaps using GIS data such as road class and population density. An EPA-supplied emissions factor was used to estimate transportation CO2 emissions, which is compared to several other estimates for the city's CO2 footprint.
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Subramaniam, Vishwanath. "Computational analysis of binary-fluid heat and mass transfer in falling films and droplets." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26485.
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Thesis (Ph.D)--Mechanical Engineering, Georgia Institute of Technology, 2009.Committee Chair: Garimella, Srinivas; Committee Member: Fuller, Tom; Committee Member: Jeter, Sheldon; Committee Member: Lieuwen, Tim; Committee Member: Wepfer, William. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Park, Sun-kyoung. "Particulate Modeling and Control Strategy of Atlanta, Georgia." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7541.
Full textAbstract:
Particles reduce visibility, change climate, and affect human health. In 1997, the National Ambient Air Quality Standard (NAAQS) for PM2.5 (particles less than 2.5 mm) was promulgated. The annual mean PM2.5 mass concentrations in Atlanta, Georgia exceed the standard, and control is needed. The first goal of this study is to develop the control strategies of PM2.5 in Atlanta, Georgia. Based on the statistical analysis of measured data, from 22% to 40% of emission reductions are required to meet the NAAQS at 95% CI. The estimated control levels can be tested using the Community Multiscale Air Quality (CMAQ) model to better assess if the proposed levels will achieve sufficient reduction in PM2.5. The second goal of this study is to analyze various uncertainties residing in CMAQ. For the model to be used in such applications with confidence, it needs to be evaluated. The model performance is calculated by the relative agreement between volume-averaged predictions and point measurements. Up to 14% of the model error for PM2.5 mass is due to the different spatial scales of the two values. CMAQ predicts PM2.5 mass concentrations reasonably well, but CMAQ significantly underestimates PM2.5 number concentrations. Causes of the underestimation include that assumed inaccurate particle density and particle size of the primary emissions in CMAQ, in addition to the expression of the particle size with three lognormal distributions. Also, the strength and limitations of CMAQ in performing PM2.5 source apportionment are compared with those of the Chemical Mass Balance with Molecular Markers. Finally, the accuracy of emissions, one of the important inputs of CMAQ, is evaluated by the inverse modeling. Results show that base level emissions for CO and SO2 sources are relatively accurate, whereas NH3, NOx, PEC and PMFINE emissions are overestimated. The emission adjustment for POA and VOC emissions is significantly different among regions.
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Kriel, Dawid Eduard. "Prediction and measurement of the performance of spray cooled heat exchangers." Thesis, Stellenbosch : Stellenbosch University, 1991. http://hdl.handle.net/10019.1/69378.
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Thesis (MEng) -- Stellenbosch University, 1991.ENGLISH ABSTRACT: In the present study various mathematical models have been developed for the analysis of spray cooled finnned-tube heat exchangers. These models range from simplified models based on the work by Kreid et al. [78KR1], Nakayama et al. [88NA1] and Erens et al. [90ER1] to a more comprehensive model based on the work by Poppe [84P01]. Computer programs were written to evaluate the performance prediction of these models on spray cooled heat exchangers in the vertical air flow mode. Experimental tests were conducted on a four-row finned-tube heat exchanger in a vertical air /water mist flow to verify the mathematical models and it was found that the performance of this heat exchanger could be predicted within 20 per cent using the accurate model. Significant performance enhancement (up to 3.5 times the dry performance) was found by spraying relatively small amounts of water onto the heat exchanger. The spray water massflow rate was found to have a significant effect on the two phase pressure drop across the heat exchanger. The present study indicated certain important factors which have to be taken into consideration when designing spray cooled heat exchanger units. These include the geometry of the finned-tubes, the temperature difference between the process water and the optimum air and the air /spray water ratio.
AFRIKAANSE OPSOMMING: In die tesis is 'n aantal wiskundige modelle ontwikkel wat gebruik kan word vir die analise van sproei verkoelde vinbuis warmte uitruilers. Die wiskundige modelle wissel van eenvoudige modelle wat gebaseer is op die werk van Kreid et al. [78KR1 ], Nakayama et al. [88NA1] en Erens et al. [90ER1] tot 'n omvattende model wat gebaseer is op die werk van Poppe [84 PO 1]. Rekenaar programme is geskryf om die die modelle se voorspellingsvermoe van die kapasiteit van sproei verkoelde warmte uitruilers te evalueer. 'n Eksperimentele ondersoek is gedoen op 'n warmte uitruiler met vier vinbuis rye in 'n toetsseksie met vertikale lugvloei. Die toets resultate is gebruik vir die evaluasie van die wiskundige modelle en het getoon dat die akkurate model se voorspellings binne 20 per sent van die gemete kapasitiet van die uitruiler val. Die eksperirnentele werk het verder aangetoon dat deur klein hoeveelhede water op die uitruiler te sproei, 'n toename in kapasiteit tot 3.5 keer die droe werkverrigting moontlik is. Die twee-fase drukval oor die uitruiler is sterk bei:nvloed deur die sproei water massavloei. Die analitiese navorsmg wat gedoen is met behulp van die rekenaar programme het aangedui dat daar 'n paar belangrike faktore is wat in ag geneem moet word met die ontwerp van sproei verkoelde warmte uitruilers. Die faktore sluit die vinbuis geometrie, die temperatuur verskil tussen die proses water en lug en optimum lug/sproeiwater massavloei verhouding in.