The Experts below are selected from a list of 5727 Experts worldwide ranked by ideXlab platform
Martin G. Mansell - One of the best experts on this subject based on the ideXlab platform.
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The impact of the variability and periodicity of rainfall on surface water supply systems in Scotland
Journal of Water and Climate Change, 2015Co-Authors: Muhammad Afzal, Alexandre S. Gagnon, Martin G. MansellAbstract:This paper analyses the impact of the variability and periodicity of rainfall on the reliability of water supply systems in Scotland. A conceptual rainfall-runoff model was used to simulate catchment runoff, and the reliability of 29 notional and six actual reservoirs was calculated using a simple storage model. The relationship between water supply reliability and the variability of rainfall was then investigated using different measures of variability. A strong correlation was found between reservoir reliability and measures representing the distribution of rainfall between the winter and summer seasons, as well as the cumulative sum (CUSUM) of annual precipitation, quantifying the variability of rainfall between years. In contrast, mainly the intra-annual CUSUM range and the variance of monthly precipitation influenced the reliability of River-Intake schemes. The presence of periodic patterns in rainfall anomalies was found to be more prevalent in West Scotland, where reservoir reliability is on average lower than in the East. In addition, a sensitivity analysis revealed the small influence of evapotranspiration on reservoir reliability in comparison to rainfall variability. This study reveals the measures of variability most affecting the reliability of surface water supplies in Scotland, and could therefore help with their management in the context of future climate change.
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The impact of projected changes in climate variability on the reliability of surface water supply in Scotland
Water Supply, 2015Co-Authors: Muhammad Afzal, Alexandre S. Gagnon, Martin G. MansellAbstract:Projected changes in precipitation and evapotranspiration under climate change and their impacts on the reliability of six water storage reservoirs and two River Intake schemes in Scotland are examined. A conceptual rainfall–runoff model was used to simulate catchment runoff which, together with evapotranspiration, served as inputs into a reservoir model. Outputs from a regional climate model coupled with a weather generator indicate an increase in rainfall variability and evapotranspiration throughout the 21st century, resulting in a decrease in both the time-based and volumetric reliability of the reservoirs under the assumption of an unchanging demand, albeit with a less drastic reduction for the volumetric approach. It was found that the variability of rainfall had the greatest effect on reservoir reliability, outweighing the positive effect of an increase in total annual precipitation, while evapotranspiration had a lesser impact. A more drastic reduction in reliability was observed for the River Intake schemes given their lack of storage capacity. The increase in water demand based on demographic projections further reduced reservoir reliability, especially when monthly variations in demand were taken into account. This paper concludes by suggesting adaptive strategies to deal with the projected changes in the supply and demand for water.
Yushi Wang - One of the best experts on this subject based on the ideXlab platform.
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Structural Modification of a Power Plant’s River Water Intake to Minimize Ice Blockage
Volume 1: Fuels and Combustion Material Handling Emissions; Steam Generators; Heat Exchangers and Cooling Systems; Turbines Generators and Auxiliaries, 2013Co-Authors: Frank Michell, Marcela Politano, Jeffrey Stallings, Yushi WangAbstract:Ice blockage of a power plant’s water Intake is of paramount importance since it can lead to an unplanned shutdown of the Intake compromising water supply and plant operation. American Electric Power’s (AEP) Conesville Power Plant historically controlled ice accumulation at the River Intake by routing to the Intake a portion of the warm water return from the condenser on the only operating “once-through” unit’s circulating water system. The unit operating with this once-through cooling system was retired at the end of 2012; thus, the plant lost the use of the condenser outlet/warm water return deicing flow at the River Intake.A numerical study was conducted to evaluate design alternatives to alleviate ice accumulation at the River Intake. A numerical model to predict the ice transport and accumulation at the River Intake was developed and used to understand the main phenomenon leading to Intake blockage.The effectiveness of mitigation measures was evaluated with the model. A mitigation plan consisting of Intake modifications to be implemented during several phases is presented. In the first phase, large pipe openings are cut in the walls separating Intake pump wells of previously retired units at the facility. In the second phase, a number of sediment control vanes previously placed in front of the Intake are removed to facilitate downstream ice transport. A third phase, if needed to be implemented, involves removing additional sedimentation control vanes and cutting holes in the pump wells on the operating units.The paper describes the model, discusses numerical results and presents the field experience after implementation of phase one.Copyright © 2013 by ASME
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structural modification of a power plant s River water Intake to minimize ice blockage
Volume 1: Fuels and Combustion Material Handling Emissions; Steam Generators; Heat Exchangers and Cooling Systems; Turbines Generators and Auxiliaries, 2013Co-Authors: Frank Michell, Marcela Politano, Jeffrey Stallings, Yushi WangAbstract:Ice blockage of a power plant’s water Intake is of paramount importance since it can lead to an unplanned shutdown of the Intake compromising water supply and plant operation. American Electric Power’s (AEP) Conesville Power Plant historically controlled ice accumulation at the River Intake by routing to the Intake a portion of the warm water return from the condenser on the only operating “once-through” unit’s circulating water system. The unit operating with this once-through cooling system was retired at the end of 2012; thus, the plant lost the use of the condenser outlet/warm water return deicing flow at the River Intake.A numerical study was conducted to evaluate design alternatives to alleviate ice accumulation at the River Intake. A numerical model to predict the ice transport and accumulation at the River Intake was developed and used to understand the main phenomenon leading to Intake blockage.The effectiveness of mitigation measures was evaluated with the model. A mitigation plan consisting of Intake modifications to be implemented during several phases is presented. In the first phase, large pipe openings are cut in the walls separating Intake pump wells of previously retired units at the facility. In the second phase, a number of sediment control vanes previously placed in front of the Intake are removed to facilitate downstream ice transport. A third phase, if needed to be implemented, involves removing additional sedimentation control vanes and cutting holes in the pump wells on the operating units.The paper describes the model, discusses numerical results and presents the field experience after implementation of phase one.Copyright © 2013 by ASME
Muhammad Afzal - One of the best experts on this subject based on the ideXlab platform.
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The impact of the variability and periodicity of rainfall on surface water supply systems in Scotland
Journal of Water and Climate Change, 2015Co-Authors: Muhammad Afzal, Alexandre S. Gagnon, Martin G. MansellAbstract:This paper analyses the impact of the variability and periodicity of rainfall on the reliability of water supply systems in Scotland. A conceptual rainfall-runoff model was used to simulate catchment runoff, and the reliability of 29 notional and six actual reservoirs was calculated using a simple storage model. The relationship between water supply reliability and the variability of rainfall was then investigated using different measures of variability. A strong correlation was found between reservoir reliability and measures representing the distribution of rainfall between the winter and summer seasons, as well as the cumulative sum (CUSUM) of annual precipitation, quantifying the variability of rainfall between years. In contrast, mainly the intra-annual CUSUM range and the variance of monthly precipitation influenced the reliability of River-Intake schemes. The presence of periodic patterns in rainfall anomalies was found to be more prevalent in West Scotland, where reservoir reliability is on average lower than in the East. In addition, a sensitivity analysis revealed the small influence of evapotranspiration on reservoir reliability in comparison to rainfall variability. This study reveals the measures of variability most affecting the reliability of surface water supplies in Scotland, and could therefore help with their management in the context of future climate change.
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The impact of projected changes in climate variability on the reliability of surface water supply in Scotland
Water Supply, 2015Co-Authors: Muhammad Afzal, Alexandre S. Gagnon, Martin G. MansellAbstract:Projected changes in precipitation and evapotranspiration under climate change and their impacts on the reliability of six water storage reservoirs and two River Intake schemes in Scotland are examined. A conceptual rainfall–runoff model was used to simulate catchment runoff which, together with evapotranspiration, served as inputs into a reservoir model. Outputs from a regional climate model coupled with a weather generator indicate an increase in rainfall variability and evapotranspiration throughout the 21st century, resulting in a decrease in both the time-based and volumetric reliability of the reservoirs under the assumption of an unchanging demand, albeit with a less drastic reduction for the volumetric approach. It was found that the variability of rainfall had the greatest effect on reservoir reliability, outweighing the positive effect of an increase in total annual precipitation, while evapotranspiration had a lesser impact. A more drastic reduction in reliability was observed for the River Intake schemes given their lack of storage capacity. The increase in water demand based on demographic projections further reduced reservoir reliability, especially when monthly variations in demand were taken into account. This paper concludes by suggesting adaptive strategies to deal with the projected changes in the supply and demand for water.
M.w. Loerop - One of the best experts on this subject based on the ideXlab platform.
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MICHIGAN'S SOURCE-WATER ASSESSMENT PROGRAM - SURFACE-WATER ASSESSMENTS LEADING TO PROTECTION INITIATIVES
Proceedings of the Water Environment Federation, 2002Co-Authors: M.j. Sweat, B.b. Brogren, R.s. Jodoin, T.a. Rossi, M.w. LoeropAbstract:Michigan has 67 water supplies that use surface-water sources. These supplies provide drinking water to over 60 percent of the State’s population, or about 6 million people. The U.S. Geological Survey and Michigan Department of Environmental Quality are cooperating on a project to assess the risk to community surface-water sources from potential contaminant sources. Section 1453a of Public Law 104-182, reauthorization of the Safe Drinking Water Act of 1996, requires Federal guidance and defines State requirements for a source-water assessment program. The U.S. Environmental Protection Agency published the State Source-water Assessment and Protection Programs Guidance in August 1997 to assist States in developing an acceptable source-water assessment program. By statute, a State’s source-water assessment program must complete assessments for all sources of public drinking water that (1) define source-water areas, (2) list potential contaminant sites and contaminants of concern, and (3) determine raw water susceptibility to contamination. States then must work with public-water suppliers to inform the public of these results. Results of the assessments are to be presented in reports for each surface-water facility. Inland lake and River Intake assessments (8 supplies in Michigan) are watershed based. The assessment process for these source waters includes reviewing water-quality monitoring records and identifying potential contaminant sources. Great Lakes and Great Lakes Connecting Channels Intake assessments (59 supplies) follow the “Assessment Protocol for Great Lakes Sources” developed by Great Lakes States in U.S. Environmental Protection Agency Region 5. Assessments include local data on land-use, contamination sources (sewer outfalls, leaking storage tanks, air deposition, etc.), information from local water-plant personnel (Intake construction and location, influent quality, effects of weather, lake currents, etc.), and centralized State and Federal data resources (census data, permitted discharges). A pilot assessment completed for the Alpena, Michigan, water supply identified potential effects to the Intake from a nearby River, atmospheric conditions, and two storm-sewer outfalls. The preliminary Alpena assessment was received favorably by the community, and provided the basis of a source-water protection program for the community. In addition to methods established for the assessment of Great Lakes supplies, assessments of supplies that use Great Lakes Connecting Channels as their source (14 supplies) will be included in a two-dimensional, hydrodynamic flow model of the St. Clair River–Lake St. Clair–Detroit River system. The flow model will define source-water areas, track contaminant source-waterquality concerns, and assist in developing contingency plans. A partnership established among the Michigan Department of Environmental Quality, U.S. Geological Survey, U.S. Environmental Protection Agency, U.S. Army Corps of Engineers, and the Detroit Water and
Frank Michell - One of the best experts on this subject based on the ideXlab platform.
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Structural Modification of a Power Plant’s River Water Intake to Minimize Ice Blockage
Volume 1: Fuels and Combustion Material Handling Emissions; Steam Generators; Heat Exchangers and Cooling Systems; Turbines Generators and Auxiliaries, 2013Co-Authors: Frank Michell, Marcela Politano, Jeffrey Stallings, Yushi WangAbstract:Ice blockage of a power plant’s water Intake is of paramount importance since it can lead to an unplanned shutdown of the Intake compromising water supply and plant operation. American Electric Power’s (AEP) Conesville Power Plant historically controlled ice accumulation at the River Intake by routing to the Intake a portion of the warm water return from the condenser on the only operating “once-through” unit’s circulating water system. The unit operating with this once-through cooling system was retired at the end of 2012; thus, the plant lost the use of the condenser outlet/warm water return deicing flow at the River Intake.A numerical study was conducted to evaluate design alternatives to alleviate ice accumulation at the River Intake. A numerical model to predict the ice transport and accumulation at the River Intake was developed and used to understand the main phenomenon leading to Intake blockage.The effectiveness of mitigation measures was evaluated with the model. A mitigation plan consisting of Intake modifications to be implemented during several phases is presented. In the first phase, large pipe openings are cut in the walls separating Intake pump wells of previously retired units at the facility. In the second phase, a number of sediment control vanes previously placed in front of the Intake are removed to facilitate downstream ice transport. A third phase, if needed to be implemented, involves removing additional sedimentation control vanes and cutting holes in the pump wells on the operating units.The paper describes the model, discusses numerical results and presents the field experience after implementation of phase one.Copyright © 2013 by ASME
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structural modification of a power plant s River water Intake to minimize ice blockage
Volume 1: Fuels and Combustion Material Handling Emissions; Steam Generators; Heat Exchangers and Cooling Systems; Turbines Generators and Auxiliaries, 2013Co-Authors: Frank Michell, Marcela Politano, Jeffrey Stallings, Yushi WangAbstract:Ice blockage of a power plant’s water Intake is of paramount importance since it can lead to an unplanned shutdown of the Intake compromising water supply and plant operation. American Electric Power’s (AEP) Conesville Power Plant historically controlled ice accumulation at the River Intake by routing to the Intake a portion of the warm water return from the condenser on the only operating “once-through” unit’s circulating water system. The unit operating with this once-through cooling system was retired at the end of 2012; thus, the plant lost the use of the condenser outlet/warm water return deicing flow at the River Intake.A numerical study was conducted to evaluate design alternatives to alleviate ice accumulation at the River Intake. A numerical model to predict the ice transport and accumulation at the River Intake was developed and used to understand the main phenomenon leading to Intake blockage.The effectiveness of mitigation measures was evaluated with the model. A mitigation plan consisting of Intake modifications to be implemented during several phases is presented. In the first phase, large pipe openings are cut in the walls separating Intake pump wells of previously retired units at the facility. In the second phase, a number of sediment control vanes previously placed in front of the Intake are removed to facilitate downstream ice transport. A third phase, if needed to be implemented, involves removing additional sedimentation control vanes and cutting holes in the pump wells on the operating units.The paper describes the model, discusses numerical results and presents the field experience after implementation of phase one.Copyright © 2013 by ASME
