Estimating the thermal properties of soil and concrete piles from thermal response tests (TRTs) for energy piles with spiral tubes

Thermal response curves that depict the probability of occurrence along a thermal gradient are used to derive various species’ thermal properties and abilities to cope with warming. However, different thermal responses can be expected for different portions of a species range. We focus on differences in thermal response curves (TRCs) and thermal niche requirements for four freshwater fishes (Coregonus sardinella, Pungitius pungitius, Rutilus rutilus, Salvelinus alpinus) native to Europe at (1) the global and (2) European continental scale. European ranges captured only a portion of the global thermal range with major differences in the minimum (Tmin), maximum (Tmax) and average temperature (Tav) of the respective distributions. Further investigations of the model-derived preferred temperature (Tpref), warming tolerance (WT = Tmax − Tpref), safety margin (SM = Tpref − Tav) and the future climatic impact showed substantially differing results. All considered thermal properties either were under- or overestimated at the European level. Our results highlight that, although continental analyses have an impressive spatial extent, they might deliver misleading estimates of species thermal niches and future climate change impacts, if they do not cover the full species ranges. Studies and management actions should therefore favor whole global range distribution data for analyzing species responses to environmental gradients.

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Multidisciplinary Approaches for Assessing a High Temperature Borehole Thermal Energy Storage Facility at Linköping, Sweden

Energies ◽

10.3390/en14144379 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4379

Author(s):

Max Hesselbrandt ◽

Mikael Erlström ◽

Daniel Sopher ◽

Jose Acuna

Keyword(s):

Thermal Properties ◽

High Temperature ◽

Energy Storage ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Thermal Response ◽

Site Investigation ◽

Thermal Response Test ◽

Response Test ◽

Crystalline Bedrock

Assessing the optimal placement and design of a large-scale high temperature energy storage system in crystalline bedrock is a challenging task. This study applies and evaluates various methods and strategies for pre-site investigation for a potential high temperature borehole thermal energy storage (HT-BTES) system at Linköping in Sweden. The storage is required to shift approximately 70 GWh of excess heat generated from a waste incineration plant during the summer to the winter season. Ideally, the site for the HT-BTES system should be able to accommodate up to 1400 wells to 300 m depth. The presence of major fracture zones, high groundwater flow, anisotropic thermal properties, and thick Quaternary overburden are all factors that play an important role in the performance of an HT-BTES system. Inadequate input data to the modeling and design increases the risk of unsatisfactory performance, unwanted thermal impact on the surroundings, and suboptimal placement of the HT-BTES system, especially in a complex crystalline bedrock setting. Hence, it is crucial that the subsurface geological conditions and associated thermal properties are suitably characterized as part of pre-investigation work. In this study, we utilize a range of methods for pre-site investigation in the greater Distorp area, in the vicinity of Linköping. Ground geophysical methods, including magnetic and Very Low-Frequency (VLF) measurements, are collected across the study area together with outcrop observations and lab analysis on rock samples. Borehole investigations are conducted, including Thermal Response Test (TRT) and Distributed Thermal Response Test (DTRT) measurements, as well as geophysical wireline logging. Drone-based photogrammetry is also applied to characterize the fracture distribution and orientation in outcrops. In the case of the Distorp site, these methods have proven to give useful information to optimize the placement of the HT-BTES system and to inform design and modeling work. Furthermore, many of the methods applied in the study have proven to require only a fraction of the resources required to drill a single well, and hence, can be considered relatively efficient.

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Improved p(t)-linear Average Method for Ground Thermal Properties Estimation during in-situ Thermal Response Test

Procedia Engineering ◽

10.1016/j.proeng.2015.09.020 ◽

2015 ◽

Vol 121 ◽

pp. 726-734 ◽

Cited By ~ 4

Author(s):

Linfeng Zhang ◽

Quan Zhang ◽

José Acuña ◽

Xiaowei Ma

Keyword(s):

Thermal Properties ◽

Average Method ◽

Thermal Response ◽

Thermal Response Test ◽

Response Test

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Estimation of thermal properties of the ground and backfilling materials from thermal response tests (TRTs) using ground heat exchangers

Energy Procedia ◽

10.1016/j.egypro.2019.01.051 ◽

2019 ◽

Vol 158 ◽

pp. 91-96

Author(s):

Liwen Zhang ◽

Gang Liu ◽

Min Li

Keyword(s):

Thermal Properties ◽

Heat Exchangers ◽

Thermal Response ◽

Ground Heat Exchangers

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Thermal Fluid-Structure Coupling for Atmospheric Entries

ASME/JSME 2011 8th Thermal Engineering Joint Conference ◽

10.1115/ajtec2011-44233 ◽

2011 ◽

Author(s):

Ojas Joshi ◽

Pe´ne´lope Leyland

Keyword(s):

Heat Transfer ◽

Thermal Properties ◽

Thermal Response ◽

Space Vehicle ◽

Structural Components ◽

Fluid Structure ◽

Coupling Techniques ◽

Heat Loads ◽

Transfer Mechanisms

This paper deals with the modeling of aero-thermal aspects of a space vehicle during its entry phase into an atmosphere. We treat the numerical coupling techniques between the external and internal aero-thermo-dynamics (ATD) produced by the interaction of ATD fields with the structural components. The thermal properties induced within the structure via heat transfer mechanisms of convection, conduction and radiation is taken into account presenting multi-disciplinary coupling between the aero-thermo-dynamics, the heat loads and the structural thermal response.

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Detection of Thermal Transport on Chip Using Gate-Induced Drain Leakage Current

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17810 ◽

2020 ◽

Vol 20 (8) ◽

pp. 4980-4984

Author(s):

Nak Won Yoo ◽

Seoungwook Choi ◽

Jun Yeon Yun ◽

Young June Park

Keyword(s):

Heat Capacity ◽

Thermal Properties ◽

Leakage Current ◽

Thermal Transport ◽

Thermal Response ◽

Wave Form ◽

Thermal Sensor ◽

Sinusoidal Wave ◽

On Chip ◽

Small Overlap

In this paper, we propose a method to detect thermal transport suitable in nanometers scale. It is feasible using the GIDL-biased MOSFET as thermal sensor. It is because the GIDL current is occurred due to the band-to-band tunnelling of the electron in a small overlap region between gate and drain. Using the relation between the thermal transport and the thermal properties (the heat resistivity and heat capacity), we conducted two ways to heat up. By generating heat in the step and sinusoidal wave form with a transistor and observing the response at other place, we were able to estimate the speed of heat on the chip. The thermal response is measured by the GIDL current of another MOSFET. The speed of the heat generated at the MOSFET is measured about 2.12 m/s.

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