Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 18 of 18 for “"ground heat"”.
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On the determination of the ground heat flux in micrometeorology and its influence on the energy balance closure
The ground heat flux (heat exchange between the atmosphere and the soil), plays a major role in micrometeorology. This is especially true for bare soils in the morning hours, but also for agricultural sites at any time of the day. Thus, this dissertation focuses on three issues: firstly, to …
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Modelling and Experimental Characterization of Solar-Assisted Ground Source Heat Pump Systems with and without Thermal Energy Storage for Cold Climates
… of low energy technologies for building heating and cooling. Among the efficient energy technologies and systems developed to enhance efficiency and reduce building carbon footprint, the use of ground source heat pumps (GSHPs) is gaining traction as a cost-competitive, reliable, and …
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Influence of Climate Variability on Terrestrial Hydrology in North America
… longwave radiation, surface temperature and ground heat flux in North America show a seesaw (or wavelike) spatial pattern.
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Ground source heat storage and thermo-physical response of soft clay
Ground source heat storage can condition buildings with reduced consumption of fossil fuels, an important issue in modem building design. However, seasonal heat storage can cause soil temperature fluctuations and possibly deformation of soft clays. This thesis evaluates the thermo-mechanical …
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Thermal sustainability of low-temperature geothermal energy systems: System interactions and environmental impacts.
In storing heat during summer for use in winter, the ground provides a better source/sink of heat than the outside air in regards to heat pump efficiency, being cooler than the outside air in the summer and warmer in the winter. Due to their good efficiency, the use of geothermal energy is often …
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Investigation of covariability between energy fluxes and CO2 exchange over a semi-arid savanna (Kruger National Park) by Eddie Covariance Technique
… that the correlation between NEE and latent heat flux (LE) and net radiation (Rn) is generally the strongest, while ground heat flux (G) and sensible heat flux (H) have little impact on NEE. The dataset provides insight into the biometeorological and flow dynamics of the Skukuza ecosystem and …
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An investigation into the performance of a very shallow borehole thermal energy store for a solar-assisted ground source heat pump
Ground-source heat pumps (GSHP) have been used in building applications to meet heating needs at lower energy costs. Likewise, solar thermal systems have been integrated into conventional GSHP to reduce the size of the ground heat exchanger and provide seasonal heat storage. So far, this technology …
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Numerical Analysis of Thermal Behavior and Fluid Flow in Geothermal Energy Piles
Geothermal heat exchangers are a growing energy technology that improve the energy efficiency of heating and cooling systems in buildings. Vertical borehole heat exchangers (BHE) coupled with ground source heat pumps have been widely developed and researched in the past century. The major …
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Transpiration and the water relations of barley
… The model uses as inputs net radiation, ground heat flux, temperature, humidity, windspeed, leaf area index and effective soil water potential. Most of these are easily measured or estimated. The model predicts leaf water potential as well as transpiration and is potentially useful in the …
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Essays on Households' Technology Choices and Long-Term Energy Use
… of three essays on households' choice of heating technology at the moment of building a new detached house. The analyses make use of Finnish administrative registry data to study how sensitive these investments are to electricity prices and how socio-demographic characteristics of …
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Strategic Roadmapping and Technology Portfolio Selection for Heating Decarbonization in Canada
Heating systems contribute significantly to Canada’s greenhouse gas emissions, accounting for approximately 117 megatons of CO₂ equivalent. demanding urgent decarbonization to meet national climate targets. This thesis employs the Advanced Technology Roadmap Architecture framework, integrating …
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Estimation of turbulent surface heat fluxes using sequences of remotely sensed land surface temperature
Fluxes of heat and moisture at the land-surface play a significant role in the climate system. These fluxes interact with the overlying atmosphere and influence the characteristics of the planetary boundary layer (e.g. temperature and water vapor content), ultimately influencing the presence and …
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Investigation of a heat pump reversible in an organic Rankine cycle and its application in the building sector
This thesis studies the concept of reversible heat pump / organic Rankine cycle (HP/ORC) and its application in the building sector. Chapter one describes this HP/ORC system and its possible applications. A tool based on operating maps is developed to determine the feasibility of such a system …
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Numerical modelling of geothermal borehole heat exchanger systems
… efficiency in buildings, in particular their heating, ventilation, and air conditioning (HVAC) systems, a policy objective for reducing energy consumption and CO2 emissions nationally and internationally. Ground source heat pump (GSHP) systems, due to their high coefficient of performance …
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Solar Colletors Combined with Ground-Source Heat Pumps in Dwellings - Analyses of System Performance
The use of ground-source heat pumps for heating buildings and domestic hot water in dwellings is increasing rapidly in Sweden. The heat pump extracts heat from the ground by a U-pipe in a vertical borehole. In order to reduce the electricity demand in the system, the combination with solar …
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Novel disturbance regimes in the Arctic: paleoecological perspectives on fire and thermo-erosion from Alaskan tundra
… such as wildfire and thermo-erosion (i.e., ground subsidence transport of ice-rich sediments) have increased in frequency and magnitude in tundra ecoregions in recent decades. These novel disturbance regimes could increase the role of the Arctic in exacerbating climate warming through the …
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Energy Efficient Passenger Comfort in Underground Subway Environments
Underground subway systems provide an efficient high capacity public transportation method for commuters within dense urban areas. Passengers using underground subway systems are subjected to enclosed and crowded environments that must be controlled to maintain tolerable temperatures and …
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Influence of head-moisture treatment on functional, colour and thermal properties of bambara ground-nut starch
Heat-moisture treatment (HMT) is a physical modification that alters the physicochemical properties of starch without changing its molecular structure. The objective of the study was to investigate the influence of HMT on the functional, colour and thermal properties of bambara groundnut (BG) …