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(1 - 7 of 7)
- Title
- VERIFICATION OF FAA'S EMISSIONS AND DISPERSION MODELING SYSTEM (EDMS).
- Creator
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Martin, Anjoli, Wayson, Roger, University of Central Florida
- Abstract / Description
-
Air quality has been a major environmental concern for many years. Recently the issue of airport emissions has presented growing concerns and is being studied in much more depth. Airport emissions come from a variety of point, line and area sources, making emissions modeling for airports very complex and more involved. Accurate air quality models, specific to airport needs, are required to properly analyze this complex array of air pollution sources created by airports. Accurate air quality...
Show moreAir quality has been a major environmental concern for many years. Recently the issue of airport emissions has presented growing concerns and is being studied in much more depth. Airport emissions come from a variety of point, line and area sources, making emissions modeling for airports very complex and more involved. Accurate air quality models, specific to airport needs, are required to properly analyze this complex array of air pollution sources created by airports. Accurate air quality models are needed to plan for increased growth of current airports and address concerns over proposed new ones. The Federal Aviation Administration's (FAA) Emissions and Dispersion Modeling System (EDMS) is a program that is the required model for assessing emissions from airport sources. This research used EDMS Version 4.21, which incorporates the EPA dispersion model AERMOD, to model detailed airport data and compare the model's predicted values to the actual measured carbon monoxide concentrations at 25 locations at a major U.S. airport. Statistics relating the model characteristics as well as trends are presented. In this way, a thorough investigation of the accuracy of the EDMS modeled values of carbon monoxide was possible. EDMS modeling included two scenarios, the first scenario referred to as practice detail included general airport information that a modeler could find from the airport being studied and the second scenario referred to as research detail utilized very detailed information from observer logs during a three day observation period. Each of the modeling scenarios was compared to the field measured data and to each other. These comparisons are important to insure the model is adequately describing emissions sources at airports. Data analysis of this study was disappointing since measured levels of CO were generally higher than modeled values. Since EDMS is continually changing and improving perhaps these results can help enhance future models.
Show less - Date Issued
- 2006
- Identifier
- CFE0001282, ucf:46903
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001282
- Title
- PREDICTING AIR QUALITY NEAR ROADWAY INTERSECTIONS THROUGH THE APPLICATION OF A GAUSSIAN PUFF MODEL TO MOVING SOURCES.
- Creator
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Kim, Brian, Wayson, Roger, University of Central Florida
- Abstract / Description
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With substantial health and economic impacts attached to many highway-related projects, it has become imperative that the models used to assess air quality be as accurate as possible. The United States (US) Environmental Protection Agency (EPA) currently promulgates the use of CAL3QHC to model concentrations of carbon monoxide (CO) near roadway intersections. This model uses steady-state and macroscopic methods to model the physical phenomena (e.g., emission rates, atmospheric dispersion, etc...
Show moreWith substantial health and economic impacts attached to many highway-related projects, it has become imperative that the models used to assess air quality be as accurate as possible. The United States (US) Environmental Protection Agency (EPA) currently promulgates the use of CAL3QHC to model concentrations of carbon monoxide (CO) near roadway intersections. This model uses steady-state and macroscopic methods to model the physical phenomena (e.g., emission rates, atmospheric dispersion, etc.) occurring at intersections. These methods are not straightforward and unintuitive for the users. Therefore, this project investigated the possibility of developing a model that is theoretically more realistic and flexible than CAL3QHC. The new model entitled, Traffic Air Quality Simulation Model (TRAQSIM), uses a microscopic approach by modeling vehicle movements and dispersion in a simulation environment. Instead of steady-state plume equations used in the CAL3QHC model, TRAQSIM uses a discrete puff methodology that can be used to model time-based dispersion of pollutants. Most of the components incorporated into TRAQSIM have been drawn from existing methodologies and therefore, are not new. However, the combination of these different methods into a single integrated model is new and presents a novel approach to such a model. Initial verification and sensitivity/trend studies of the model indicate that TRAQSIM uses reasonable/realistic traffic parameters and behaves intuitively correct. A validation study showed that TRAQSIM produces good results when compared to actual measured data with an overall R2 value of 0.605 for 11 scenarios comprising 264 data points. Although most statistical parameters showed CAL3QHC agrees better overall with measured data (R2 value of 0.721), the comparisons were mixed on a scenario-by-scenario basis; that is, CAL3QHC showed better results for 6 scenarios and TRAQSIM showed better results for 5 scenarios. Additional tests with larger datasets, which were beyond the scope of this work, could be conducted to obtain more definitive conclusions and allow further development of TRAQSIM. While CAL3QHC is a mature model that has been developed over many years, TRAQSIM is new and has much more potential for improvement. The physical parameters used in TRAQSIM allow it to be more directly (more logically) improved than the approximations used in CAL3QHC. In addition, although the fundamental-level modeling in TRAQSIM make it a more complex model internally, it is much more intuitive for the user to understand and use.
Show less - Date Issued
- 2004
- Identifier
- CFE0000316, ucf:46306
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000316
- Title
- Near-road Dispersion Modeling of Mobile Source Air Toxics (MSATs) in Florida.
- Creator
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Westerlund, Kurt, Cooper, Charles, Radwan, Ahmed, Randall, Andrew, Hall, Steven, University of Central Florida
- Abstract / Description
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There is a growing public concern that emissions of mobile source air toxics (MSATs) from motor vehicles may pose a threat to human health. At present, no state or federal agencies require dispersion modeling of these compounds, but many agencies are concerned about potential future requirements. Current air pollution professionals are familiar with Federal Highway Administration (FHWA) and U.S. Environmental Protection Agency (EPA) requirements for dispersion modeling to produce predicted...
Show moreThere is a growing public concern that emissions of mobile source air toxics (MSATs) from motor vehicles may pose a threat to human health. At present, no state or federal agencies require dispersion modeling of these compounds, but many agencies are concerned about potential future requirements. Current air pollution professionals are familiar with Federal Highway Administration (FHWA) and U.S. Environmental Protection Agency (EPA) requirements for dispersion modeling to produce predicted concentrations for comparison with appropriate standards. This research examined a method in which the potential near-road concentrations of MSATs were calculated. It was believed that by assessing MSATs in much the same way that are used for other pollutants, the model and methods developed in this research could become a standard for those quantifying MSAT concentrations near-roadways.This dissertation reports on the results from short-term (1-hour) and long-term (annual average) MSATs dispersion modeling that has been conducted on seven intersections and seven freeway segments in the state of Florida. To accomplish the modeling, the CAL3QHC model was modified to handle individual MSAT emissions input data and to predict the concentrations of several MSATs around these roadway facilities. Additionally, since the CAL3MSAT model is DOS based and not user-friendly, time was invested to develop a Windows(&)#174; graphical user interface (GUI). Real-world data (traffic volumes and site geometry) were gathered, worst-case meteorology was selected, mobile source emission factors (EFs) were obtained from MOVES2010a, and worst-case modeling was conducted. Based on a literature search, maximum acceptable concentrations (MACs) were proposed for comparison with the modeled results, for both a short-term (1-hour) averaging time and a long-term (1-year) averaging time.Results from this CAL3MSAT modeling study indicate that for all of the intersections and freeway segments, the worst-case 1-hour modeled concentrations of the MSATs were several orders of magnitude below the proposed short-term MACs. The worst-case 1-year modeled concentrations were of the same order of magnitude as the proposed long-term MACs.The 1-year concentrations were first developed by applying a persistence factor to the worst-case 1-hour concentrations. In the interest of comparing the predicted concentrations from the CAL3MSAT persistence factor approach to other dispersion models, two EPA regulatory models (CAL3QHCR and AERMOD) with the ability to account for yearly meteorology, traffic, and signal timing were used. Both hourly and annual MSAT concentrations were predicted at one large urban intersection and compared for the three different dispersion models. The short-term 1-hour results from CAL3MSAT were higher than those predicted by the two other models due to the worst-case assumptions. Similarly, results indicate that the CAL3MSAT persistence factor approach predicted a worst-case annual average concentration on the same order of magnitude as the two other more refined models. This indicated that the CAL3MSAT model might be useful as a worst-case screening approach.
Show less - Date Issued
- 2013
- Identifier
- CFE0004772, ucf:49804
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004772
- Title
- DEVELOPMENT OF A GRAPHICAL USER INTERFACE FOR CAL3QHC CALLED CALQCAD.
- Creator
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Gawalpanchi, Sheetal, Cooper, Charles, University of Central Florida
- Abstract / Description
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One of the major sources of air pollution in the United States metropolitan areas is due to automobiles. With the huge growth of motor vehicles and, greater dependence on them, air pollution problems have been aggravated. According to the EPA, nearly 95% of carbon monoxide (CO ) (EPA 1999) in urban areas comes from mobile sources, of which 51% is contributed by on road vehicles. It is well known fact that, carbon monoxide is one of the major mobile source pollutants and CO has detrimental...
Show moreOne of the major sources of air pollution in the United States metropolitan areas is due to automobiles. With the huge growth of motor vehicles and, greater dependence on them, air pollution problems have been aggravated. According to the EPA, nearly 95% of carbon monoxide (CO ) (EPA 1999) in urban areas comes from mobile sources, of which 51% is contributed by on road vehicles. It is well known fact that, carbon monoxide is one of the major mobile source pollutants and CO has detrimental effects on the human health. Carbon monoxide is the result of mainly incomplete combustion of gasoline in motor vehicles (FDOT 1996). The National Environmental Policy Act (NEPA) gives important considerations to the actions to be taken. Transportation conformity . The Clean Air Act Amendments (CAAA, 1970) was an important step in meeting the National Ambient Air Quality Standards In order to evaluate the effects of CO and Particulate Matter (PM) impacts based on the criteria for NAAQS standards, it is necessary to conduct dispersion modeling of emissions for mobile source emissions. Design of transportation engineering systems (roadway design) should take care of both the flow of the traffic as well as the air pollution aspects involved. Roadway projects need to conform to the State Implementation Plan (SIP) and meet the NAAQS. EPA guidelines for air quality modeling on such roadway intersections recommend the use of CAL3QHC. The model has embedded in it CALINE 3.0 (Benson 1979) – a line source dispersion model based on the Gaussian equation. The model requires parameters with respect to the roadway geometry, fleet volume, averaging time, surface roughness, emission factors, etc. The CAL3QHC model is a DOS based model which requires the modeling parameters to be fed into an input file. The creation of input the file is a tedious job. Previous work at UCF, resulted in the development of CALQVIEW, which expedites this process of creating input files, but the task of extracting the coordinates still has to be done manually. The main aim of the thesis is to reduce the analysis time for modeling emissions from roadway intersections, by expediting the process of extracting the coordinates required for the CAL3QHC model. Normally, transportation engineers design and model intersections for the traffic flow utilizing tools such as AutoCAD, Microstation etc. This thesis was to develop advanced software allowing graphical editing and coordinates capturing from an AutoCAD file. This software was named as CALQCAD. This advanced version will enable the air quality analyst to capture the coordinates from an AutoCAD 2004 file. This should expedite the process of modeling intersections and decrease analyst time from a few days to few hours. The model helps to assure the air quality analyst to retain accuracy during the modeling process. The idea to create the standalone interface was to give the AutoCAD user full functionality of AutoCAD tools in case editing is required to the main drawing. It also provides the modeler with a separate graphical user interface (GUI).
Show less - Date Issued
- 2005
- Identifier
- CFE0000483, ucf:46364
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000483
- Title
- A STUDY OF CENTRAL FLORIDA NONROAD VOC AND NOX EMISSIONS AND POTENTIAL ACTIONS TO REDUCE EMISSIONS.
- Creator
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Radford, Michael, Cooper, C. David, University of Central Florida
- Abstract / Description
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Ground-level ozone is harmful to the human respiratory system, as well as the environment. The national EPA 8-hour ozone standard for ground-level ozone was reduced from 85 parts per billion (ppb) to 75 ppb in 2008, and trends from previous years show that some of the counties in Central Florida could be in danger of violation. Violation means "non attainment" status; in which the county is ordered by EPA to develop specific implementation plans to reduce its emissions. The objective of this...
Show moreGround-level ozone is harmful to the human respiratory system, as well as the environment. The national EPA 8-hour ozone standard for ground-level ozone was reduced from 85 parts per billion (ppb) to 75 ppb in 2008, and trends from previous years show that some of the counties in Central Florida could be in danger of violation. Violation means "non attainment" status; in which the county is ordered by EPA to develop specific implementation plans to reduce its emissions. The objective of this study was to compile an emissions inventory of volatile organic compounds (VOCs) and nitrogen oxides (NOx) from nonroad equipment in Osceola, Seminole, and Orange Counties (OSO) in Central Florida, and to develop possible action steps to reduce those emissions. This is important because VOC and NOx emissions are precursors to ground-level ozone. Thus, compiling emissions inventories is important to identify high VOC and NOx emitters. Mobile and point sources have long been the highest emitters of VOC and NOx and have therefore been targeted and monitored since the Clean Air Act of 1970, but the nonroad sources (such as construction and lawn equipment) have only been regulated since the 1990s. Using the NONROAD and NMIM modeling programs, the highest nonroad emitters of VOC for Central Florida were found to be lawn/garden equipment, and boating equipment, emitting a combined percentage of 77% of the total nonroad mobile source VOC. Construction equipment contributed 67% of the total nonroad mobile source emissions of NOx in Central Florida. The components of these categories were also analyzed to find the largest individual sources of VOC and NOx. Of the individual sources, lawn mowers and outboard boat engines were found to be the largest sources of VOCs. Of the NOx sources, all the construction equipment components had a relatively similar level of NOx emissions. Next, action steps were developed to reduce emissions, focusing on the high emitters, along with an estimated cost and feasibility for each measure. Of these steps, implementing a ban on leafblowers, and reducing use of lawn mowers, edgers, trimmers, etc. seemed to be the most effective for reducing VOCs. Although these are effective measures, the cost and feasibility of both pose challenges. The best action step for reducing NOx emissions in construction equipment seemed to be by simply reducing idling of equipment on job sites. This also poses challenges in feasibility and enforcement by management. Further, constant on/off cycles could result in decreasing the useful life of the older construction equipment. Finally, a survey was conducted with various construction managers and companies to find out the typical equipment and quantity needed for land clearing/grubbing, as well as the typical use, idling time, and total project time for each piece of equipment on a 10-acre site, under various conditions. The purpose of the study was to develop a rough estimate for the average amount of VOC and NOx emissions that will be produced per acre of land clearing activities, and to estimate the emissions reductions and cost savings if idling of the equipment was reduced.
Show less - Date Issued
- 2009
- Identifier
- CFE0002850, ucf:48064
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002850
- Title
- Development of a chemical kinetic model for the combustion of a synthesis gas from a fluidized-bed sewage sludge gasifier in a thermal oxidizer.
- Creator
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Martinez, Luis, Cooper, David, Randall, Andrew, Vasu Sumathi, Subith, University of Central Florida
- Abstract / Description
-
The need for sustainability has been on the rise. Municipalities are finding ways of reducing waste, but also finding ways to reduce energy costs. Waste-to-energy is a sustainable method that may reduce bio-solids volume while also producing energy. In this research study bio-solids enters a bubbling bed gasifier and within the gasifier a synthesis gas is produced. This synthesis gas exits through the top of the gasifier and enters a thermal oxidizer for combustion. The thermal oxidizer has...
Show moreThe need for sustainability has been on the rise. Municipalities are finding ways of reducing waste, but also finding ways to reduce energy costs. Waste-to-energy is a sustainable method that may reduce bio-solids volume while also producing energy. In this research study bio-solids enters a bubbling bed gasifier and within the gasifier a synthesis gas is produced. This synthesis gas exits through the top of the gasifier and enters a thermal oxidizer for combustion. The thermal oxidizer has an innovative method of oxidizing the synthesis gas. The thermal oxidizer has two air injection sites and the possibility for aqueous ammonia injection for further NOx reduction. Most thermal oxidizers already include an oxidizer such as air in the fuel before it enters the thermal oxidizer; thus making this research and operation different from many other thermal oxidizers and waste-to-energy plants.The reduction in waste means less volume loads to a landfill. This process significantly reduces the amount of bio-solids to a landfill. The energy produced from the synthesis is beneficial for any municipality, as it may be used to run the waste-to-energy facility. The purpose of this study is to determine methods in which operators may configure future plants to reduce NOx emissions. NOx mixed with volatile organic compounds (VOC) and sunlight, produce ozone (O3) a deadly gas at high concentrations.This study developed a model to determine the best methods to reduce NOx emissions. Results indicate that a fuel-rich then fuel-lean injection scheme results in lower NOx emissions. This is because at fuel-rich conditions not all of the ammonia in the first air ring is converted to NOx, but rather a partial of the ammonia is converted to NOx and N2 and then the second air ring operates at fuel-lean which further oxidizes the remaining ammonia which converts to NOx, but also a fraction to N2. If NOx standards reach more stringency then aqueous ammonia injection is a recommended method for NOx reduction; this method is also known as selective non-catalytic reduction (SNCR).The findings in this study will allow operators to make better judgment in the way that they operate a two air injection scheme thermal oxidizer. The goal of the operator and the organization is to meet air quality standards and this study aims at finding ways to reduce emissions, specifically NOx.
Show less - Date Issued
- 2014
- Identifier
- CFE0005528, ucf:50301
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005528
- Title
- Microscopic Assessment of Transportation Emissions on Limited Access Highways.
- Creator
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Abou-Senna, Hatem, Radwan, Ahmed, Abdel-Aty, Mohamed, Al-Deek, Haitham, Cooper, Charles, Johnson, Mark, University of Central Florida
- Abstract / Description
-
On-road vehicles are a major source of transportation carbon dioxide (CO2) greenhouse gas emissions in all the developed countries, and in many of the developing countries in the world. Similarly, several criteria air pollutants are associated with transportation, e.g., carbon monoxide (CO), nitrogen oxides (NOx), and particulate matter (PM). The need to accurately quantify transportation-related emissions from vehicles is essential. Transportation agencies and researchers in the past have...
Show moreOn-road vehicles are a major source of transportation carbon dioxide (CO2) greenhouse gas emissions in all the developed countries, and in many of the developing countries in the world. Similarly, several criteria air pollutants are associated with transportation, e.g., carbon monoxide (CO), nitrogen oxides (NOx), and particulate matter (PM). The need to accurately quantify transportation-related emissions from vehicles is essential. Transportation agencies and researchers in the past have estimated emissions using one average speed and volume on a long stretch of roadway. With MOVES, there is an opportunity for higher precision and accuracy. Integrating a microscopic traffic simulation model (such as VISSIM) with MOVES allows one to obtain precise and accurate emissions estimates. The new United States Environmental Protection Agency (USEPA) mobile source emissions model, MOVES2010a (MOVES) can estimate vehicle emissions on a second-by-second basis creating the opportunity to develop new software (")VIMIS 1.0(") (VISSIM/MOVES Integration Software) to facilitate the integration process. This research presents a microscopic examination of five key transportation parameters (traffic volume, speed, truck percentage, road grade and temperature) on a 10-mile stretch of Interstate 4 (I-4) test bed prototype; an urban limited access highway corridor in Orlando, Florida. The analysis was conducted utilizing VIMIS 1.0 and using an advanced custom design technique; D-Optimality and I-Optimality criteria, to identify active factors and to ensure precision in estimating the regression coefficients as well as the response variable.The analysis of the experiment identified the optimal settings of the key factors and resulted in the development of Micro-TEM (Microscopic Transportation Emissions Meta-Model). The main purpose of Micro-TEM is to serve as a substitute model for predicting transportation emissions on limited access highways to an acceptable degree of accuracy in lieu of running simulations using a traffic model and integrating the results in an emissions model. Furthermore, significant emission rate reductions were observed from the experiment on the modeled corridor especially for speeds between 55 and 60 mph while maintaining up to 80% and 90% of the freeway's capacity. However, vehicle activity characterization in terms of speed was shown to have a significant impact on the emission estimation approach.Four different approaches were further examined to capture the environmental impacts of vehicular operations on the modeled test bed prototype. First, (at the most basic level), emissions were estimated for the entire 10-mile section (")by hand(") using one average traffic volume and average speed. Then, three advanced levels of detail were studied using VISSIM/MOVES to analyze smaller links: average speeds and volumes (AVG), second-by-second link driving schedules (LDS), and second-by-second operating mode distributions (OPMODE). This research analyzed how the various approaches affect predicted emissions of CO, NOx, PM and CO2. The results demonstrated that obtaining accurate and comprehensive operating mode distributions on a second-by-second basis improves emission estimates. Specifically, emission rates were found to be highly sensitive to stop-and-go traffic and the associated driving cycles of acceleration, deceleration, frequent braking/coasting and idling. Using the AVG or LDS approach may overestimate or underestimate emissions, respectively, compared to an operating mode distribution approach.Additionally, model applications and mitigation scenarios were examined on the modeled corridor to evaluate the environmental impacts in terms of vehicular emissions and at the same time validate the developed model (")Micro-TEM("). Mitigation scenarios included the future implementation of managed lanes (ML) along with the general use lanes (GUL) on the I-4 corridor, the currently implemented variable speed limits (VSL) scenario as well as a hypothetical restricted truck lane (RTL) scenario. Results of the mitigation scenarios showed an overall speed improvement on the corridor which resulted in overall reduction in emissions and emission rates when compared to the existing condition (EX) scenario and specifically on link by link basis for the RTL scenario.The proposed emission rate estimation process also can be extended to gridded emissions for ozone modeling, or to localized air quality dispersion modeling, where temporal and spatial resolution of emissions is essential to predict the concentration of pollutants near roadways.
Show less - Date Issued
- 2012
- Identifier
- CFE0004777, ucf:49788
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004777
