Analytical solutions are developed for modeling steady state gas flow to a single vacuum extracti... more Analytical solutions are developed for modeling steady state gas flow to a single vacuum extraction well in the unsaturated zone. The solutions are applicable to isotropic as well as anisotropic homogeneous subsurface media in which the ground surface is open to the atmosphere. Analytic expressions are given for the gas pressure field, and for the stream function distribution. Streamline travel times are computed using a simple numerical technique employing the analytical solutions. The pressure solution may be used to analyze in situ gas pumping tests to determine average horizontal and vertical gas permeabilities. The stream function solution and streamline travel times may be used to optimize the design of vapor extraction systems for volatile organic chemical removal from the unsaturated zone. Application of the solutions to several examples illustrates the strong effect of screen location and anisotropy on the induced gas flow field, and dimensionless type curves are given for ...
This report was prepared under contract to the Department of Defense Environmental Security Techn... more This report was prepared under contract to the Department of Defense Environmental Security Technology Certification Program (ESTCP). The publication of this report does not indicate endorsement by the Department of Defense, nor should the contents be construed as reflecting the official policy or position of the Department of Defense. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the Department of Defense.
: The objective of this demonstration was to fully maximize the inherent advantages of the geolog... more : The objective of this demonstration was to fully maximize the inherent advantages of the geology and hydrogeology accessed by means of Ground-loop Heat Exchangers (GHX) with closed loop systems or via direct ground water use with open-loop systems, which conventional GHP systems in the U.S. are not designed to achieve. Deliberately engineered UTES systems not only allow for the waste heat of cooling systems and the waste cool of heating systems to be captured, but also allow for the out-of-season capture of the winters cold or summers heat (from the air or via solar thermal collectors), if needed, in cooling-dominated or heating-dominated buildings, respectively.
: EW-201135, Coupling Geothermal Heat Pumps (GHPs) with Underground Thermal EnergyStorage (USTES)... more : EW-201135, Coupling Geothermal Heat Pumps (GHPs) with Underground Thermal EnergyStorage (USTES) was proposed because, in the US, the fundamental design of GHP systems,with their underground Groundloop Heat Exchanger (GHX) or water supply wells, has beenlargely unchanged for decades, while the international design community has progressed to moreinnovative and efficient architectures. Energy consumption associated with Heating, Ventilationand Air-Conditioning (HVAC) systems are generally a significant contributor to a buildingsentire energy consumption. In pursuit of reducing energy consumption, the HVAC industry istypically progressing to develop various types of HVAC technology to help reduce the energyconsumption of an associated HVAC system. Historically, conventional GHP HVAC systemsare considered one of the most, if not the most efficient active HVAC systems. Most DoD (andnon-DoD commercial) facilities in many geographic regions are cooling dominated due to theconsistent pres...
Analytical solutions are developed for modeling steady state gas flow to a single vacuum extracti... more Analytical solutions are developed for modeling steady state gas flow to a single vacuum extraction well in the unsaturated zone. The solutions are applicable to isotropic as well as anisotropic homogeneous subsurface media in which the ground surface is open to the atmosphere. Analytic expressions are given for the gas pressure field, and for the stream function distribution. Streamline travel times are computed using a simple numerical technique employing the analytical solutions. The pressure solution may be used to analyze in situ gas pumping tests to determine average horizontal and vertical gas permeabilities. The stream function solution and streamline travel times may be used to optimize the design of vapor extraction systems for volatile organic chemical removal from the unsaturated zone. Application of the solutions to several examples illustrates the strong effect of screen location and anisotropy on the induced gas flow field, and dimensionless type curves are given for ...
This report was prepared under contract to the Department of Defense Environmental Security Techn... more This report was prepared under contract to the Department of Defense Environmental Security Technology Certification Program (ESTCP). The publication of this report does not indicate endorsement by the Department of Defense, nor should the contents be construed as reflecting the official policy or position of the Department of Defense. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the Department of Defense.
: The objective of this demonstration was to fully maximize the inherent advantages of the geolog... more : The objective of this demonstration was to fully maximize the inherent advantages of the geology and hydrogeology accessed by means of Ground-loop Heat Exchangers (GHX) with closed loop systems or via direct ground water use with open-loop systems, which conventional GHP systems in the U.S. are not designed to achieve. Deliberately engineered UTES systems not only allow for the waste heat of cooling systems and the waste cool of heating systems to be captured, but also allow for the out-of-season capture of the winters cold or summers heat (from the air or via solar thermal collectors), if needed, in cooling-dominated or heating-dominated buildings, respectively.
: EW-201135, Coupling Geothermal Heat Pumps (GHPs) with Underground Thermal EnergyStorage (USTES)... more : EW-201135, Coupling Geothermal Heat Pumps (GHPs) with Underground Thermal EnergyStorage (USTES) was proposed because, in the US, the fundamental design of GHP systems,with their underground Groundloop Heat Exchanger (GHX) or water supply wells, has beenlargely unchanged for decades, while the international design community has progressed to moreinnovative and efficient architectures. Energy consumption associated with Heating, Ventilationand Air-Conditioning (HVAC) systems are generally a significant contributor to a buildingsentire energy consumption. In pursuit of reducing energy consumption, the HVAC industry istypically progressing to develop various types of HVAC technology to help reduce the energyconsumption of an associated HVAC system. Historically, conventional GHP HVAC systemsare considered one of the most, if not the most efficient active HVAC systems. Most DoD (andnon-DoD commercial) facilities in many geographic regions are cooling dominated due to theconsistent pres...
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