Готові списки джерел за темами / Thermal energy measurement

Добірка наукової літератури з теми "Thermal energy measurement"

Автор: Grafiati

Опубліковано: 14 березня 2023

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Статті в журналах з теми "Thermal energy measurement"

Vakulin, A. A., and A. V. Shavlov. "Error of measurement of thermal energy." Measurement Techniques 41, no. 4 (April 1998): 355–58. http://dx.doi.org/10.1007/bf02504018.

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Iskandarov, N. Sh. "Improving the accuracy of temperature measurements in heat supply systems." SOCAR Proceedings, no. 2 (June 30, 2022): 084–87. http://dx.doi.org/10.5510/ogp20220200679.

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The constant rise in energy prices leads to an increase in the cost of thermal energy, which is used in heat supply systems for industrial and residential premises. Therefore, improving the accuracy of measuring the heat supplied to consumers is an urgent task. Instrumental metering of heat energy requires regular measurement of the temperature of the coolant in the pipelines of the heat supply system. There is an opinion that all the problems of measuring temperature when accounting for thermal energy have been solved. However, this is not the case. The analysis shows that the systematic component of the error in measuring the temperature and the temperature difference between the supply and return pipelines, especially in conditions of small values of the difference, makes a significant contribution to the instrumental error of accounting for thermal energy. The article discusses solutions to minimize these errors in temperature measurement, taking into account the consumption of thermal energy. Keywords: temperature measurements; measurement error; thermal energy; thermodynamics; metrology.

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Utomo, Bayu, Nanang Kusnandar, Himma Firdaus, Intan Paramudita, Iput Kasiyanto, Qudsiyyatul Lailiyah, and Wahyudin P. Syam. "Comparison of GUM and Monte Carlo Methods for Measurement Uncertainty Estimation of the Energy Performance Measurements of Gas Stoves." Measurement Science Review 22, no. 4 (May 14, 2022): 160–69. http://dx.doi.org/10.2478/msr-2022-0020.

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Abstract The paper presents the comparison of uncertainty measurement estimations of the energy performances of gas stoves. The Guide to the Expression of Uncertainty in Measurement (GUM) framework and two Monte Carlo Simulation (MCM) approaches: ordinary and adaptive MCM were applied for the energy performance uncertainty: thermal energy and efficiency measurement uncertainties. The validation of the two MCMs is performed by comparing the MCM estimations to the GUM estimations for the thermal energy and efficiency measurement results. A test method designed in Indonesia National Standard SNI 7368:2011 was employed for the thermal energy and efficiency determinations. The results of the GUM and two MCM methods are in good agreement for the estimation of the thermal energy value. Significant differences of the uncertainty estimations for the thermal energy and efficiency results are observed for both GUM and MCM methods. Both the ordinary and adaptive MCM estimations give larger coverage interval compared to the GUM method. The adaptive MCM can give similar estimations with a much lower number of iterations compared to the ordinary MCM. From the estimation difference between the GUM and MCM methods, suggestions are needed for the improvement in measurement models for thermal energy and efficiency of the standard.

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Błaszczak, Paweł, and Roman Stryczek. "Measurement of Energy Consumption During a Thermal Drilling Cycle." Pomiary Automatyka Robotyka 27, no. 1 (February 20, 2023): 93–98. http://dx.doi.org/10.14313/par_247/93.

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The work presents the issue of measuring and analyzing energy consumption during a thermal drilling cycle. A research stand based on a CNC lathe was presented, the equipment of which was an experimental energy consumption system based on an electricity meter and a force gauge. The measuring devices used allowed for recording the load on the power grid, the load on the machine tool drives, the axial force, the drill braking torque, the current rotation of the machine tool spindle, the position of the drill in relation to the workpiece and the values of auxiliary parameter registers in the strategy of adaptive feed control. Two cases of a drilling cycle were considered: making a single hole and making a series of holes in one cycle. Five feed control strategies were tested during the drilling cycle, including adaptive feed control and a recursive feed optimization method. For comparison, holes were also made with traditional HSS twist drills. Based on the obtained test results, it can be concluded that the friction drilling method can be included in the energy-saving methods of making holes in thin-walled elements.

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Palacios, Anabel, Lin Cong, M. E. Navarro, Yulong Ding, and Camila Barreneche. "Thermal conductivity measurement techniques for characterizing thermal energy storage materials – A review." Renewable and Sustainable Energy Reviews 108 (July 2019): 32–52. http://dx.doi.org/10.1016/j.rser.2019.03.020.

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Górecki, Krzysztof, and Krzysztof Posobkiewicz. "Selected Problems of Power MOSFETs Thermal Parameters Measurements." Energies 14, no. 24 (December 11, 2021): 8353. http://dx.doi.org/10.3390/en14248353.

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In the paper, selected problems that are related to the measurements of thermal parameters of power MOSFETs that are placed on a common heat sink are analysed. The application of the indirect electrical method, the contact method, and the optical method in measuring self and mutual transient thermal impedances of these transistors is presented. The circuits that are required to perform measurements are presented and described. The errors of measurements are assessed for each of the considered methods. In the case of the indirect electrical method, an additional influence of the selection of a thermo-sensitive parameter and the function approximating thermometric characteristics on the measurement error are taken into consideration. The measurement results of the thermal parameters of the investigated transistors that were obtained using the considered measurement methods in various supply conditions are presented and discussed.

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Wang, Lin, and Hong Wang. "Measurement and Application of Radiant Energy." Advanced Materials Research 503-504 (April 2012): 1463–67. http://dx.doi.org/10.4028/www.scientific.net/amr.503-504.1463.

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Based on the application of radiant energy in various fields, the fundamental knowledge about incident radiation, including physical quantities and units, is summarized. Then, the category and principle of radiant energy detector are introduced, i.e. thermal detectors and photodetectors. Also, their application conditions are compared. It is significantly important for users to understand their operation principles and to choose an appropriate radiation measuring detector.

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Wurster, Dale Eric, and J. Richard Creekmore. "Measurement of the Thermal Energy Evolved upon Tablet Compression." Drug Development and Industrial Pharmacy 12, no. 10 (January 1986): 1511–28. http://dx.doi.org/10.3109/03639048609065874.

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Chipulis, V. P. "Adequacy of Measurement Results in Accounting for Thermal Energy." Measurement Techniques 59, no. 5 (August 2016): 516–20. http://dx.doi.org/10.1007/s11018-016-1000-7.

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Levashenko, G. I., A. S. Sokol'nikov, I. N. Dobrokhotov, and N. V. Mazaev. "Measurement of energy characteristics of an impulsive thermal radiator." Combustion, Explosion, and Shock Waves 29, no. 1 (1993): 43–46. http://dx.doi.org/10.1007/bf00755327.

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Дисертації з теми "Thermal energy measurement"

Faghani, Farshad. "Thermal conductivity Measurement of PEDOT:PSS by 3-omega Technique." Thesis, Linköpings universitet, Fysik och elektroteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-63317.

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Conducting polymers (CP) have received great attention in both academic and industrial areas in recent years. They exhibit unique characteristics (electrical conductivity, solution processability, light weight and flexibility) which make them promising candidates for being used in many electronic applications. Recently, there is a renewed interest to consider those materials for thermoelectric generators that is for energy harvesting purposes. Therefore, it is of great importance to have in depth understanding of their thermal and electrical characteristics. In this diploma work, the thermal conductivity of PEDOT:PSS is investigated by applying 3-omega technique which is accounted for a transient method of measuring thermal conductivity and specific heat. To validate the measurement setup, two benchmark substrates with known properties are explored and the results for thermal conductivity are nicely in agreement with their actual values with a reasonable error percentage. All measurements are carried out inside a Cryogenic probe station with vacuum condition. Then a bulk scale of PEDOT:PSS with sufficient thickness is made and investigated. Although, it is a great challenge to make a thick layer of this polymer since it needs to be both solid state and has as smooth surface as possible for further gold deposition. The results display a thermal conductivity range between 0.20 and 0.25 (W.m-1.K-1) at room temperature which is a nice approximation of what has been reported so far. The discrepancy is mainly due to some uncertainty about the exact value of temperature coefficient of resistance (TCR) of the heater and also heat losses especially in case of heaters with larger surface area. Moreover, thermal conductivity of PEDOT:PSS is studied over a wide temperature band ranging from 223 - 373 K.

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Van, Nijnatten Peter A. "Measurement and modelling tools for the evaluation of directional optical and thermal radiation properties of glazing." Thesis, Oxford Brookes University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247601.

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PISTACCHIO, STEFANO. "Experimental measurement of the Molten Salts (MS) Thermal Conductivity and verification of the Thermocline stability in Thermal Energy Storage (TES) system." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2015. http://hdl.handle.net/2108/202929.

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A Thermal conductivity probe fo rhigh temperature(HT-TCP) has been built and tested. Its design and construction procedure are adapted from the ambient temperature ther- mal conductivity probe(AT-TCP) due to the good performance softhislast.The construction procedure and the preliminary tests are accurately described.The probe contains a PtwireasheaterandatypeKthermocouple(K-TC)as temperature sensor, and its size are so small (diameter0.6mmandlength60mm) to guaranteea length to diameter ratioofabout100.Calibration tests with glycerolfor temperatures between 0C and 60C have shown a good Agreement with literature data,within3%.First tests on aternarysalt(18%inmassof NaNO3, 52% KNO3, and30% LiNO3) at120C and 150C , have given good results:an Agreement was found with the Thermal conduc- tivity of the standard solar salt(60% NaNO3, 40% KNO3), even if the data for this last have been extrapolated,being it solidat those temperatures. Unfortunately, at the higher temperaturetested(200C), the viscosityof the salt highly decreases,and free convection starts, making the measurements unreliable. A numerica linvestigation of the performance of the storage and evolution of the ther- mocline for theOPTSFull scaleconguration and for the OPTSsystem of theEnea Casaccia facility is carriedon.The full scale conguration has a tankheightinthe order of12m,because this choice allow stop operate the systeminnatural convection regime forlow charge fraction softh e storage.In order to obtainnumerical results in a time scalesuitable with computer resources and activities, the adoption of anaxisym- metric simplication of the geometriesis pursuit. The code OpenFOAMversion2.2.0 is used to perform the simulations. Code and model settings together with the adopted computational grids,initia land boundary conditionsare described in the following sec- tions. A summary of the simulation results is then given. A steady-state numerical investigation of the MSHeatExchanger prototype developed in ENEA Casaccia is presented.This component is realized to perform the heat exchange between moltensalts(aternarymixture ) and adiathermicoil and with a moderate tem- peraturegap(38C). In order to optimize the heate xchangereciency and toobtain the greatest contact are a between uids the pipe line series of diathermicoil is designed with anhelical geometry.The moltensaltsside is aconvectionalcy lindricalgeome- try with the Greater diameter in the region where pipe line series are located while the other portion of the heater has a diameter lower than the length of the cylinder.The codeOpenFOAMversion2.2.0 is use d to perform the simulations for the discharging phase. Code and model settings together with the adopted computational grids, initial and boundary conditions are described in the following sections and summary of the simulation results is then given.

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Ahmad, Naveed. "Measurement of energy performance : Analysis of QUB method." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI051.

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QUB est une méthode d'essai de caractérisation thermique in situ dynamique qui a le potentiel d'être menée sur une courte durée d'une à deux nuits. La robustesse de la méthode QUB avec l'incertitude du niveau de puissance (pendant la phase de chauffage QUB), l'incertitude du coefficient de transfert de chaleur global à l'état d'équilibre, H_ref, et les températures extérieures en fonction des saisons doivent être établies pour les bâtiments réels. Un modèle dynamique d'état-espace est développé dans cette thèse pour simuler des expériences QUB. La modélisation espace-état consiste à générer un circuit thermique pour chaque composant du bâtiment (murs, fenestration, système de ventilation, etc.). Les circuits thermiques sont ensuite assemblés pour générer un seul circuit pour l'ensemble du bâtiment. Le modèle d'espace d'état développé, est validé à l'aide des caractéristiques thermiques et des données mesurées d'une maison à grande échelle (la maison jumelle) fournies par l'annexe 58 de l'IEA EBC. Les simulations numériques des expériences QUB sur une maison montrent que la méthode ne présente que de légères variations avec une incertitude de puissance; par exemple, une erreur de 30% de la puissance optimale peut provoquer une erreur à moins de 3% de la valeur de référence. Une analyse d'erreur a posteriori est effectuée en simulant des expériences QUB dans des situations où l'enveloppe réelle a des caractéristiques différentes de celles supposées dans la conception de l'expérience pour la méthode QUB. Ces résultats sont ensuite comparés à des erreurs a priori, une situation dans laquelle des expériences QUB sont effectuées avec la connaissance de l'enveloppe réelle. L'analyse des erreurs montre qu'avec une erreur de 50% du coefficient de transfert de chaleur global (c'est-à-dire une situation d'isolation de paroi manquante), la méthode QUB entraîne une erreur accrue de seulement 3¬¬%. La précision de la méthode QUB a également été testée avec la variation du rayonnement solaire. Les résultats QUB les jours nuageux montrent une variation moindre par rapport aux jours ensoleillés. Il a été démontré que le transfert de chaleur des radiations solaires retardées pénétrant à travers les murs du bâtiment a un effet sur l'évolution de la température au cours de l'expérience QUB. Cela peut entraîner une augmentation de l'erreur dans la méthode QUB. Les expériences QUB sont simulées pendant l'été et l'hiver pour déterminer l'impact des saisons sur la précision de la méthode. La saison d'hiver montre des résultats plus robustes que les mois d'été. Les mois d'été montrent une plus grande variation des résultats. Il est vérifié que la grande variation est due à une petite différence de température entre les conditions intérieures et extérieures pendant certaines des nuits d'été. Les expériences en saison estivale peuvent être améliorées en augmentant la température de consigne avant l'expérience QUB
QUB is a dynamic in-situ thermal characterization test method that has the potential to be conducted in a short duration of one to two nights. The robustness of QUB method with uncertainty in power level (during QUB heating phase), uncertainty in overall heat transfer coefficient at steady state, H_ref, and the outdoor temperatures a function of seasons needs to be established for real buildings.A dynamic state-space model is developed in this thesis to simulate QUB experiments. The state-space modelling involves generating a thermal circuit for each component of the building (walls, fenestration, ventilation system, etc.). The thermal circuits are then assembled to generate a single circuit for the entire building. The state-space model developed, is validated using thermal characteristics and measured data of a full-scale house (the twin house) provided by IEA EBC Annex 58. The numerical simulations of the QUB experiments on a house show that the method has only slight variation with uncertainty in power; for example, 30% error in optimum power can cause an error within 3 % of the reference value. A posteriori error analysis is performed by simulating QUB experiments in situations in which the real envelope has different characteristics than those assumed in the design of the experiment for QUB method. These results are then compared with a priori errors, a situation in which QUB experiments are performed with the knowledge of the real envelope. The error analysis shows that with 50 % error in the overall heat transfer coefficient (i.e. missing wall insulation situation), the QUB method results in an increased error of only 3¬¬ %. The precision of QUB method was tested also with the variation of solar radiation. QUB results on cloudy days show lesser variation as compared to sunny days. It was shown that the heat transfer from the delayed solar radiations entering through the walls of the building has an effect on the temperature evolution during the QUB experiment. This can lead to an increased error in QUB method. The QUB experiments are simulated during summer and winter to determine the impact of seasons on the accuracy of the method. The winter season shows more robust results as compared to summer months. The summer months show larger variation of results. It is verified that the large variation are due to small temperature difference between indoor and outdoor conditions during some of the summer nights. The experiments in summer season can be improved by increasing the set point temperature before the QUB experiment

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ZAMPETTI, LORENZO. "Development of a low-cost system for thermal comfort measurement and control." Doctoral thesis, Università Politecnica delle Marche, 2017. http://hdl.handle.net/11566/245525.

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Questa tesi di dottorato presenta lo sviluppo e la validazione di alcuni sistemi innovativi ed a basso costo per il monitoraggio ed il controllo di ambienti interni. I sistemi presentati in questo documento trovano le loro origini nel Comfort Eye, un sistema di misura del comfort termoigrometrico già presentato in letteratura. Questo dispositivo è in grado di misurare in maniera innovativa alcune tra le più rilevanti grandezze ambientali, riuscendo ad ottenere dei valori in real-time del comfort per più punti dell’ambiente in esame, secondo la norma ISO 7726. Partendo da questo punto, è stato progettato e testato un nuovo prototipo di Comfort Eye, cercando di migliorare le prestazioni di misura e le funzionalità. Attraverso l’analisi delle prestazioni dei singoli sensori adottati e seguendo le linee guida della GUM (Guide to the expression of Uncertainty in Measurement), si è calcolata un’accuratezza del sistema nella misura del PMV pari a ±0.1. La seconda parte della tesi riguarda un nuovo sistema di controllo del riscaldamento ambienti utilizzando come variabile controllata le misure di comfort provenienti dal Comfort Eye. Questo sistema è stato progettato e validato con dei test in un ambiente reale di tipo ufficio, raggiungendo un risparmio energetico del 20%. La terza ed ultima parte di questo documento mostra un’altra potenziale applicazione del Comfort Eye e cioè un sistema di rilevazione di persone e sorgenti calde per ambienti interni, con avanzate potenzialità di localizzazione. Il sistema è stato sviluppato e testato in un ambiente di tipo ufficio, mostrando un’accuratezza per la detection di persone del 70%.
This PhD dissertation summarizes the development and validation of innovative low cost systems for monitoring and controlling indoor environments. The systems explained in this document have their roots in the first version of Comfort Eye, an innovative thermal comfort measurement system, which is already documented in literature. This device can measure several environmental parameters in the room to obtain a real-time comfort assessment in multiple points of the space, according to ISO 7726 standard. Starting at this point, in the first part a new prototype of the monitoring system has been developed and tested highlighting improved features and measurement performances. Through single sensors calibration and uncertainty models from the GUM (Guide to the expression of Uncertainty in Measurement), the rated accuracy of the prototype in PMV measurement is ±0.1. The second part of the thesis is regarding an innovative subzonal HVAC control system, using the comfort data provided by Comfort Eye as controlled variable. That system has been designed and validated through some tests in an office-type environment, achieving an energy saving of 20%. The third and last part of this document finally shows another potential application of the Comfort Eye sensor: a people detection system for indoor ambient, with advanced counting and locating capabilities, has been tested inside office environment. The first attempt of validation shows an accuracy of 70% in detecting people.

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Tink, Victoria J. "The measured energy efficiency and thermal environment of a UK house retrofitted with internal wall insulation." Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/33727.

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Approximately 30% of the UK s housing stock is comprised of older, solid wall buildings. Solid walls have no cavity and were built without insulation; therefore these buildings have high heat loss, can be uncomfortable for occupants throughout the winter and require an above-average amount of energy to heat. Solid wall buildings can be made more energy efficient by retrofitting internal wall insulation (IWI). However, there is little empirical evidence on how much energy can be saved by insulating solid wall buildings and there are concerns that internal wall insulation could lead to overheating in the summer. This thesis reports measured results obtained from a unique facility comprised of a matched pair of unoccupied, solid wall, semi-detached houses. In the winter of 2015 one house of the pair was fitted with internal wall insulation then both houses had their thermal performance measured to see how differently they behaved. Measuring the thermal performance was the process of measuring the wall U-values, the whole house heat transfer coefficient and the whole house airtightness of the original and insulated houses. Both houses were then monitored in the winter of 2015, monitoring was the process of measuring the houses energy demand while using synthetic occupancy to create normal occupancy conditions. In the summer of 2015 indoor temperatures were monitored in the houses to assess overheating. The monitoring was done firstly to see how differently an insulated and an uninsulated house perform under normal operating conditions: with the blinds open through the day and the windows closed. Secondly, a mitigation strategy was applied to reduce high indoor operative temperatures in the houses, which involved closing the blinds in the day to reduce solar gains and opening the windows at night to purge warm air from the houses. The original solid walls were measured to have U-values of 1.72 W/m2K, while with internal wall insulation the walls had U-values of 0.21 W/m2K, a reduction of 88%. The house without IWI had a heat transfer coefficient of 238 W/K; this was reduced by 39% to 144 W/K by installing IWI. The monitored data from winter was extrapolated into yearly energy demand; the internally insulated house used 52% less gas than before retrofit. The measured U-values, whole house heat loss and energy demand were all compared to those produced from RdSAP models. The house was found to be more energy efficient than expected in its original state and to continue to use less energy than modelled once insulated. This has important implications for potential carbon savings and calculating pay-back times for retrofit measures. In summer, operative temperatures in the living room and main bedroom were observed to be higher, by 2.2 oC and 1.5 oC respectively, in the internally insulated house in comparison to the uninsulated house. Both of these rooms overheated according to CIBSE TM52 criteria; however the tests were conducted during an exceptionally warm period of weather. With the simple mitigation strategy applied the indoor operative temperature in the internally insulated house was reduced to a similar level as observed in the uninsulated house. This demonstrates that any increased overheating risk due to the installation of internal wall insulation can be mitigated through the use of simple, low cost mitigation measures. This research contributes field-measured evidence gathered under realistic controlled conditions to show that internal wall insulation can significantly reduce the energy demand of a solid wall house; this in turn can reduce greenhouse gas emissions and could help alleviate fuel poverty. Further to this it has been demonstrated that in this archetype and location IWI would cause overheating only in unusually hot weather and that indoor temperatures can be reduced to those found in an uninsulated house through the use of a simple and low cost mitigation strategy. It is concluded that IWI can provide a comfortable indoor environment, and that overheating should not be considered a barrier to the uptake of IWI in the UK.

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Murray, Elizabeth. "Measurement of prompt gamma-ray energy distribution and multiplicity of U-235 following thermal fission using STEFF." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/measurement-of-prompt-gammaray-energy-distribution-and-multiplicity-of-u235-following-thermal-fission-using-steff(237a3928-95a1-4a5f-b905-44ad23368f98).html.

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More accurate knowledge of gamma-ray heating in nuclear reactors has beenlisted as a high priority request by the NEA [23]. In response to this the SpecTrometerfor Exotic Fission Fragments (STEFF), a 2-velocity, 2-energy spectrometer assembledby the Manchester Fission Group has been used to take measurements ofprompt gamma-rays from thermal fission of U-235. Through the procedures discussed,the average total gamma-ray energy and average multiplicity were determined to be8.40 +/- 0.26 MeV and 7.74 +/- 0.12, respectively. The single energy spectrum for eachindividual detector has been determined as well as the total energy distribution. A new parallel plate avalanche counter has been tested for its potential to improvethe timing resolution of the current STEFF stop detector. The timing resolution ofthe new detector is found to be 337 ps, an improvement of 75 % on the previous stopdetector. The pulse shapes created by a fission fragment in an ionisation chamber havebeen investigated. The relationship with fragment atomic number has been tested byemploying the Lohengrin spectrometer to separate fragments by mass so that theirindividual pulse shapes can be studied. Evaluation work has been performed at the NNL, Cumbria, under the supervisionof Dr Robert Mills. Experimental data determined from the spontaneous fission ofCf-252 has been extracted and evaluation techniques performed upon it so that thedata can be considered for inclusion within an evaluated nuclear database.

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Vera-Sorroche, Javier. "Thermal homogeneity and energy efficiency in single screw extrusion of polymers : the use of in-process metrology to quantify the effects of process conditions, polymer rheology, screw geometry and extruder scale on melt temperature and specific energy consumption." Thesis, University of Bradford, 2014. http://hdl.handle.net/10454/13965.

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Polymer extrusion is an energy intensive process whereby the simultaneous action of viscous shear and thermal conduction are used to convert solid polymer to a melt which can be formed into a shape. To optimise efficiency, a homogeneous melt is required with minimum consumption of process energy. In this work, in-process monitoring techniques have been used to characterise the thermal dynamics of the single screw extrusion process with real-time quantification of energy consumption. Thermocouple grid sensors were used to measure radial melt temperatures across the melt flow at the entrance to the extruder die. Moreover, an infrared sensor flush mounted at the end of the extruder barrel was used to measure non-invasive melt temperature profiles across the width of the screw channel in the metering section of the extruder screw. Both techniques were found to provide useful information concerning the thermal dynamics of the extrusion process; in particular this application of infrared thermometry could prove useful for industrial extrusion process monitoring applications. Extruder screw geometry and extrusion variables should ideally be tailored to suit the properties of individual polymers but in practise this is rarely achieved due the lack of understanding. Here, LDPE, LLDPE, three grades of HDPE, PS, PP and PET were extruded using three geometries of extruder screws at several set temperatures and screw rotation speeds. Extrusion data showed that polymer rheology had a significant effect on the thermal efficiency on the extrusion process. In particular, melt viscosity was found to have a significant effect on specific energy consumption and thermal homogeneity of the melt. Extruder screw geometry, set extrusion temperature and screw rotation speed were also found to have a direct effect on energy consumption and melt consistency. Single flighted extruder screws exhibited poorer temperature homogeneity and larger fluctuations than a barrier flighted screw with a spiral mixer. These results highlighted the importance of careful selection of processing conditions and extruder screw geometry on melt homogeneity and process efficiency. Extruder scale was found to have a significant influence on thermal characteristics due to changes in surface area of the screw, barrel and heaters which consequently affect the effectiveness of the melting process and extrusion process energy demand. In this thesis, the thermal and energy characteristics of two single screw extruders were compared to examine the effect of extruder scale and processing conditions on measured melt temperature and energy consumption. Extrusion thermal dynamics were shown to be highly dependent upon extruder scale whilst specific energy consumption compared more favourably, enabling prediction of a process window from lab to industrial scale within which energy efficiency can be optimised. Overall, this detailed experimental study has helped to improve understanding of the single screw extrusion process, in terms of thermal stability and energy consumption. It is hoped that the findings will allow those working in this field to make more informed decisions regarding set conditions, screw geometry and extruder scale, in order to improve the efficiency of the extrusion process.

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Antón, Remírez Raúl. "Experimental and numerical study of the thermal and hydraulic effect of EMC screens in radio base stations : detailed and compact models." Doctoral thesis, KTH, Energiteknik, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4265.

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Today’s telecommunication cabinets use Electro Magnetic Compliance (EMC) screens in order to reduce electromagnetic noise that can cause some miss functions in electronic equipment. Many radio base stations (RBSs) use a 90-degree building architecture: the flow inlet is perpendicular to the EMC screen, which creates a complex flow, with a 90-degree air turn, expansions, compressions, perforated plates and PCBs. It is of great interest to study how the EMC screen interacts with the rest of components and analyze the total pressure drop and how much the flow pattern changes due to the placement of the screen. Velocity, pressure and temperature measurements as well as flow pattern visualizations have been carried out to gain good insight into the flow and heat transfer characteristics in a subrack model of an RBS. Furthermore, these measurements have been very useful for validating detailed CFD models and evaluating several turbulence models. Nowadays, industrial competition has caused a substantial decrease in the time-to-market of products. This fact makes the use of compact models in the first stages of the design process of vital importance. Accurate and fast compact models can to a great extent decrease the time for design, and thus for production. Hence, to determine the correlations between the pressure drop and flow pattern on the PCBs as a function of the geometry and the Reynolds number, based on a detailed CFD parametric study, was one objective. Furthermore, the development of a compact model using a porous media approach (using two directional-loss coefficients) has been accomplished. Two correlations of these directional loss coefficients were found as a function of the geometry and Reynolds number.
QC 20100630

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Park, Keunhan. "Thermal Characterization of Heated Microcantilevers and a Study on Near-Field Radiation." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14597.

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Recently, remarkable advances have been made in the understanding of micro/nanoscale energy transport, opening new opportunities in various areas such as thermal management, data storage, and energy conversion. This dissertation focuses on thermally-sensed nanotopography using a heated silicon microcantilever and near-field thermophotovoltaic (TPV) energy conversion system. A heated microcantilever is a functionalized atomic force microscope (AFM) cantilever that has a small resistive heater integrated at the free end. Besides its capability of increasing the heater temperature over 1,000 K, the resistance of a heated cantilever is a very sensitive function of temperature, suggesting that the heated cantilever can be used as a highly sensitive thermal metrology tool. The first part of the dissertation discusses the thermal characterization of the heated microcantilever for its usage as a thermal sensor in various conditions. Particularly, the use of heated cantilevers for tapping-mode topography imaging will be presented, along with the recent experimental results on the thermal interaction between the cantilever and substrate. In the second part of the dissertation, the so-called near-field TPV device is introduced. This new type of energy conversion system utilizes the significant enhancement of radiative energy transport due to photon tunneling and surface polaritons. Investigation of surface and bulk polaritons in a multilayered structure reveals that radiative properties are significantly affected by polariton excitations. The dissertation then addresses the rigorous performance analysis of the near-field TPV system and a novel design of a near-field TPV device.

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Книги з теми "Thermal energy measurement"

Atzeri, Anna Maria. Energy efficiency, thermal and visuale comfort-integrated building perfomance modelling and measurement. Bozen: BU, Press, 2017.

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United States. National Environmental Satellite, Data, and Information Service., ed. Spectral radiance-temperature conversions for measurements by AVHRR thermal channels 3,4,5. Washington, D.C: U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, National Environmental Satellite, Data, and Information Service, 1993.

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Davis, Paul A. Spectral radiance-temperature conversions for measurements by AVHRR thermal channels 3,4,5. Washington, D.C: U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, National Environmental Satellite, Data, and Information Service, 1993.

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Palmiter, Larry S. Development of a simple device for field air flow measurement of residential air handling equipment: Phase II. Seattle, WA: Ecotope, 2000.

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Alexander, Burt J., and Ted F. Richardson. Concentrating solar power: Data and directions for an emerging solar technology. Hauppauge, N.Y: Nova Science Publishers, 2011.

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United States. National Aeronautics and Space Administration., ed. Radiant energy measurements from a scaled jet engine axisymmetric exhaust nozzle for a baseline code validation case. [Washington, DC]: National Aeronautics and Space Administration, 1994.

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Meier, Alan. An analysis of outliers in the RSDP. Berkeley, Calif: Applied Science Division, Lawrence Berkeley Laboratory, University of California, 1988.

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Griffiths, E. H. Thermal Measurement of Energy. University of Cambridge ESOL Examinations, 2014.

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Частини книг з теми "Thermal energy measurement"

Hamann, Hendrik F., and Vanessa López. "Data Center Metrology and Measurement-Based Modeling Methods." In Energy Efficient Thermal Management of Data Centers, 273–334. Boston, MA: Springer US, 2012. http://dx.doi.org/10.1007/978-1-4419-7124-1_7.

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Gavrilovska, Ada, Karsten Schwan, Hrishikesh Amur, Bhavani Krishnan, Jhenkar Vidyashankar, Chengwei Wang, and Matt Wolf. "Understanding and Managing IT Power Consumption: A Measurement-Based Approach." In Energy Efficient Thermal Management of Data Centers, 169–97. Boston, MA: Springer US, 2012. http://dx.doi.org/10.1007/978-1-4419-7124-1_4.

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Sharma, Avadhesh Kumar, Mayank Modak, Santosh Kumar Sahu, and Manish Kumar Agrawal. "Infrared Thermal Imaging Technique for Temperature Measurement in Various Energy Systems." In Energy, Environment, and Sustainability, 465–96. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-15-0536-2_20.

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Zhang, J., H. E. Khalifa, C. Deck, J. Sheeder, and C. A. Back. "Thermal Diffusivity Measurement of Curved Samples Using The Flash Method." In Ceramic Materials for Energy Applications V, 43–56. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2015. http://dx.doi.org/10.1002/9781119211709.ch5.

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Tang, Xiaojun, Jingzhen Han, Xin Tian, Zhiyi Zhao, and Tianli Hui. "Research on the measurement method of temperature field under thermal vacuum environment." In Advances in Energy Materials and Environment Engineering, 703–8. London: CRC Press, 2022. http://dx.doi.org/10.1201/9781003332664-98.

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Burova, Zinaida, Svitlana Kovtun, Leonid Dekusha, and Valentina Vasilevskaya. "Methodology for Designing Precision Sensors Which Using in Thermal Conductivity Measurement Systems." In Systems, Decision and Control in Energy IV, 223–38. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-22464-5_12.

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Cucchi, Chiara, Alice Lorenzati, Sebastian Treml, Christoph Sprengard, and Marco Perino. "Standard-Based Analysis of Measurement Uncertainty for the Determination of Thermal Conductivity of Super Insulating Materials." In Sustainability in Energy and Buildings, 171–84. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-32-9868-2_15.

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Wada, Katelyn, Austin Fleming, and David Estrada. "Novel Thermal Conductivity Measurement Technique Utilizing a Transient Multilayer Analytical Model of a Line Heat Source Probe for Extreme Environments." In Energy Technology 2023, 129–38. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-22638-0_13.

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Yue, Xingzuo, and Lei Wu. "A Comprehensive Energy Consumption Measurement Model for Building Envelope Components Based on Thermal Imaging Detection." In 2020 International Conference on Data Processing Techniques and Applications for Cyber-Physical Systems, 847–54. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-1726-3_104.

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Biesinger, Andreas, Ruben Pesch, Mariela Cotrado, and Dirk Pietruschka. "Increased Efficiency Through Intelligent Networking of Producers and Consumers in Commercial Areas Using the Example of Robert Bosch GmbH." In iCity. Transformative Research for the Livable, Intelligent, and Sustainable City, 105–43. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92096-8_9.

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AbstractEnergy-efficient heating and cooling systems as well as intelligent systems for energy distribution are urgently required in order to be able to meet the ambitious goals of the European Union to reduce greenhouse gas emissions. The present article is intended to show that intelligent system extensions for the area of heating, cooling and electricity production for the industrial sector can lead to significant increase in efficiency. For this purpose, a simulation study for the expansion of a combined heat and power (CHP) plant with 2 MW thermal output using a 1.4 MW absorption chiller has been carried out. This shows that a heat-controlled CHP unit can significantly increase its running time. A system model was created for the initial situation and validated with existing measurement data. In the second step, this model was expanded to include the ACM module. The simulation was able to prove that in the event of a system expansion, the run time of the CHP unit can be increased by 35%. In addition to then increase of energy efficiency in the supply system, the analysis also focuses on the efficiency of the energy distribution via thermal networks in an industrial environment. The presented paper therefore also highlights the optimization potentials in the operation of thermal supply networks for industrial applications. For this purpose, a mathematical model has been developed which in addition to the components of the thermal network itself also comprises the producers and consumers. The specific construction of thermal networks for the supply of industrial properties requires adapted solutions for the simulation of such systems. Therefore, amongst other things, in the paper, solutions are shown for the modelling of direct flow local heating networks as well as for the operation of a cascade-controlled pump group.

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Тези доповідей конференцій з теми "Thermal energy measurement"

Badruzzaman, Ahmed. "Energy security and climate change — Myths and realities." In 2014 30th Semiconductor Thermal Measurement & Management Symposium (SEMI-THERM). IEEE, 2014. http://dx.doi.org/10.1109/semi-therm.2014.6892203.

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Wang, Zhefu, and Richard B. Peterson. "Thermal Wave Based Measurement of Liquid Thermal Conductivities." In ASME 2008 Heat Transfer Summer Conference collocated with the Fluids Engineering, Energy Sustainability, and 3rd Energy Nanotechnology Conferences. ASMEDC, 2008. http://dx.doi.org/10.1115/ht2008-56418.

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This work develops an experimental technique capable of determining thermal conductivity of liquids with application to nanofluids. A periodic current passing through a thin stainless steel strip generates a periodic Joule heating source and an infrared detector measures the temperature response at the front surface of the stainless steel strip. An open chamber is machined out of a delrin plate with the stainless steel strip acting as the sealing cover. This resulting closed chamber contains the test liquid. The phase and magnitude of the temperature response were measured using a lock-in amplifier at various frequencies from 22 to 502 Hz. A one-dimensional, two-layered transient heat conduction model was developed to predict the temperature response on the front surface of the stainless steel strip. This temperature response, including phase and magnitude, is a function of the thermal properties of the liquid. The phase information shows high sensitivity to thermal properties of the liquid layer and is employed to match experimental data to find thermal conductivities. The measured thermal conductivities of water and ethylene glycol agree well with data from the literature and support the validity of this measurement technique. An aqueous fluid consisting of gold nanoparticles was tested. Anomalous thermal conductivity enhancement was observed. Our measurement results also show a divergence of thermal transport behavior between nanofluids and pure liquids. This suggests the need to carefully examine the role of measurement techniques in the study of nanofluid heat transfer phenomena.

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Klein, Levente J., Sergio Bermudez, Hans-Dieter Wehle, Stephan Barabasi, and Hendrik F. Hamann. "Sustainable data centers powered by renewable energy." In 2012 IEEE/CPMT 28th Semiconductor Thermal Measurement & Management Symposium (SEMI-THERM). IEEE, 2012. http://dx.doi.org/10.1109/stherm.2012.6188874.

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Luttrell, Jeff, Abhishek Guhe, and Dereje Agonafer. "Expanding the envelope for indirect/direct evaporative data center cooling using thermal energy storage." In 2016 32nd Thermal Measurement, Modeling & Management Symposium (SEMI-THERM). IEEE, 2016. http://dx.doi.org/10.1109/semi-therm.2016.7458461.

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KOENEN, ALAIN, and DAMIEN MARQUIS. "Walls Thermal Resistance Measurement with an Energy Room Method: Uncertainty and Analysis of Different Approaches." In Thermal Conductivity 33/Thermal Expansion 21. Lancaster, PA: DEStech Publications, Inc., 2019. http://dx.doi.org/10.12783/tc33-te21/30342.

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Wu, Xiao Ping, Masataka Mochizuki, Koichi Mashiko, Thang Nguyen, Vijit Wuttijumnong, Gerald Cabsao, Randeep Singh, and Aliakbar Akbarzadeh. "Energy conservation approach for data center cooling using heat pipe based cold energy storage system." In 2010 IEEE/CPMT 26th Semiconductor Thermal Measurement, Modeling & Management Symposium (SEMI-THERM). IEEE, 2010. http://dx.doi.org/10.1109/stherm.2010.5444304.

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Xuefei Han and Yogendra Joshi. "Energy reduction in server cooling via real time thermal control." In 2012 IEEE/CPMT 28th Semiconductor Thermal Measurement & Management Symposium (SEMI-THERM). IEEE, 2012. http://dx.doi.org/10.1109/stherm.2012.6188829.

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Parthasarathy, Swarrnna K., Khondker Z. Ahmed, Borislav Alexandrov, Satish Kumar, and Saibal Mukhopadhyay. "Energy efficient active cooling of integrated circuits using autonomous Peltier/Seebeck mode switching of a thermoelectric module." In 2014 30th Semiconductor Thermal Measurement & Management Symposium (SEMI-THERM). IEEE, 2014. http://dx.doi.org/10.1109/semi-therm.2014.6892222.

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Sahu, Vivek, Andrei G. Fedorov, Yogendra Joshi, Kazuaki Yazawa, Amirkoushyar Ziabari, and Ali Shakouri. "Energy efficient liquid-thermoelectric hybrid cooling for hot-spot removal." In 2012 IEEE/CPMT 28th Semiconductor Thermal Measurement & Management Symposium (SEMI-THERM). IEEE, 2012. http://dx.doi.org/10.1109/stherm.2012.6188838.

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Green, Matthew, Saket Karajgikar, Philip Vozza, Nick Gmitter, and Dan Dyer. "Achieving energy efficient data centers using cooling path management coupled with ASHRAE standards." In 2012 IEEE/CPMT 28th Semiconductor Thermal Measurement & Management Symposium (SEMI-THERM). IEEE, 2012. http://dx.doi.org/10.1109/stherm.2012.6188862.

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Звіти організацій з теми "Thermal energy measurement"

Johra, Hicham. Project CleanTechBlock 2 Thermal conductivity measurement of cellular glass samples. Department of the Built Environment, Aalborg University, January 2019. http://dx.doi.org/10.54337/aau307323438.

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The goal of the project CleanTechBlock 2 is to develop and test a durable and sustainable construction wall element which complies with the building regulations of 2020, and has a certain aesthetics attractiveness. The CleanTechBlock (CTB) prefabricated elements consist of cellular glass insulation blocks mounted in between two layers of brick masonry [1] [2]. The aim of this technical document is to report the results of the different experimental investigations performed on the CTB and other commercial cellular glass samples to determined their thermal conductivity. These experimental investigations have been carried out at the Laboratory of Building Energy and Indoor Environment at the Department of Civil Engineering of Aalborg University (Denmark).

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Barowy, Adam, Alex Klieger, Jack Regan, and Mark McKinnon. UL 9540A Installation Level Tests with Outdoor Lithium-ion Energy Storage System Mockups. UL Firefighter Safety Research Institute, April 2021. http://dx.doi.org/10.54206/102376/jemy9731.

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This report covers results of experiments conducted to obtain data on the fire and deflagration hazards from thermal runaway and its propagation through energy storage systems (ESS). The UL 9540A test standard provides a systematic evaluation of thermal runaway and propagation in energy storage system at cell, module, unit, and installation levels. The data from this testing may be used to design fire and explosion protection systems needed for safe siting and installation of ESS. In addition to temperature, pressure, and gas measurement instruments installed inside of the container, fire service portable gas monitors were placed at locations inside and outside the storage container during the experiments to assess their ability to detect products of thermal runaway and inform fire service size-up decisions. Review section 2.2.3 Fire Service Size-up Equipment to learn more. This research demonstrates a clear need for responding firefighters to have early access to data from instrumentation installed within an ESS, particularly gas measurement instrumentation, available through a monitoring panel. Additionally, it highlights the importance of communication between responding firefighters and personnel responsible for management of the ESS, who can aid in complete evaluation of system data to develop a more clear picture of system status and potential hazards.

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Lager, Daniel, Lia Kouchachvili, and Xavier Daguenet. TCM measuring procedures and testing under application conditions. IEA SHC Task 58, May 2021. http://dx.doi.org/10.18777/ieashc-task58-2021-0004.

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This Subtask aims to have reliable thermal analysis methods/protocols and procedures for the characterization of aterial and reaction properties for sorption and chemical reactions of thermal energy storage (TES) applications. One goal is an inventory of already standardized measurement procedures for TCM as well as of needed characterization procedures.

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Brosh, Arieh, David Robertshaw, Yoav Aharoni, Zvi Holzer, Mario Gutman, and Amichai Arieli. Estimation of Energy Expenditure of Free Living and Growing Domesticated Ruminants by Heart Rate Measurement. United States Department of Agriculture, April 2002. http://dx.doi.org/10.32747/2002.7580685.bard.

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Research objectives were: 1) To study the effect of diet energy density, level of exercise, thermal conditions and reproductive state on cardiovascular function as it relates to oxygen (O2) mobilization. 2) To validate the use of heart rate (HR) to predict energy expenditure (EE) of ruminants, by measuring and calculating the energy balance components at different productive and reproductive states. 3) To validate the use of HR to identify changes in the metabolizable energy (ME) and ME intake (MEI) of grazing ruminants. Background: The development of an effective method for the measurement of EE is essential for understanding the management of both grazing and confined feedlot animals. The use of HR as a method of estimating EE in free-ranging large ruminants has been limited by the availability of suitable field monitoring equipment and by the absence of empirical understanding of the relationship between cardiac function and metabolic rate. Recent developments in microelectronics provide a good opportunity to use small HR devices to monitor free-range animals. The estimation of O2 uptake (VO2) of animals from their HR has to be based upon a consistent relationship between HR and VO2. The question as to whether, or to what extent, feeding level, environmental conditions and reproductive state affect such a relationship is still unanswered. Studies on the basic physiology of O2 mobilization (in USA) and field and feedlot-based investigations (in Israel) covered a , variety of conditions in order to investigate the possibilities of using HR to estimate EE. In USA the physiological studies conducted using animals with implanted flow probes, show that: I) although stroke volume decreases during intense exercise, VO2 per one heart beat per kgBW0.75 (O2 Pulse, O2P) actually increases and measurement of EE by HR and constant O2P may underestimate VO2unless the slope of the regression relating to heart rate and VO2 is also determined, 2) alterations in VO2 associated with the level of feeding and the effects of feeding itself have no effect on O2P, 3) both pregnancy and lactation may increase blood volume, especially lactation; but they have no effect on O2P, 4) ambient temperature in the range of 15 to 25°C in the resting animal has no effect on O2P, and 5) severe heat stress, induced by exercise, elevates body temperature to a sufficient extent that 14% of cardiac output may be required to dissipate the heat generated by exercise rather than for O2 transport. However, this is an unusual situation and its affect on EE estimation in a freely grazing animal, especially when heart rate is monitored over several days, is minor. In Israel three experiments were carried out in the hot summer to define changes in O2P attributable to changes in the time of day or In the heat load. The animals used were lambs and young calves in the growing phase and highly yielding dairy cows. In the growing animals the time of day, or the heat load, affected HR and VO2, but had no effect on O2P. On the other hand, the O2P measured in lactating cows was affected by the heat load; this is similar to the finding in the USA study of sheep. Energy balance trials were conducted to compare MEI recovery by the retained energy (RE) and by EE as measured by HR and O2P. The trial hypothesis was that if HR reliably estimated EE, the MEI proportion to (EE+RE) would not be significantly different from 1.0. Beef cows along a year of their reproductive cycle and growing lambs were used. The MEI recoveries of both trials were not significantly different from 1.0, 1.062+0.026 and 0.957+0.024 respectively. The cows' reproductive state did not affect the O2P, which is similar to the finding in the USA study. Pasture ME content and animal variables such as HR, VO2, O2P and EE of cows on grazing and in confinement were measured throughout three years under twenty-nine combinations of herbage quality and cows' reproductive state. In twelve grazing states, individual faecal output (FO) was measured and MEI was calculated. Regression analyses of the EE and RE dependent on MEI were highly significant (P<0.001). The predicted values of EE at zero intake (78 kcal/kgBW0.75), were similar to those estimated by NRC (1984). The EE at maintenance condition of the grazing cows (EE=MEI, 125 kcal/kgBW0.75) which are in the range of 96.1 to 125.5 as presented by NRC (1996 pp 6-7) for beef cows. Average daily HR and EE were significantly increased by lactation, P<0.001 and P<0.02 respectively. Grazing ME significantly increased HR and EE, P<0.001 and P<0.00l respectively. In contradiction to the finding in confined ewes and cows, the O2P of the grazing cows was significantly affected by the combined treatments (P<0.00l ); this effect was significantly related to the diet ME (P<0.00l ) and consequently to the MEI (P<0.03). Grazing significantly increased O2P compared to confinement. So, when EE of grazing animals during a certain season of the year is estimated using the HR method, the O2P must be re measured whenever grazing ME changes. A high correlation (R2>0.96) of group average EE and of HR dependency on MEI was also found in confined cows, which were fed six different diets and in growing lambs on three diets. In conclusion, the studies conducted in USA and in Israel investigated in depth the physiological mechanisms of cardiovascular and O2 mobilization, and went on to investigate a wide variety of ruminant species, ages, reproductive states, diets ME, time of intake and time of day, and compared these variables under grazing and confinement conditions. From these combined studies we can conclude that EE can be determined from HR measurements during several days, multiplied by O2P measured over a short period of time (10-15 min). The study showed that RE could be determined during the growing phase without slaughtering. In the near future the development microelectronic devices will enable wide use of the HR method to determine EE and energy balance. It will open new scopes of physiological and agricultural research with minimizes strain on animals. The method also has a high potential as a tool for herd management.

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Johra, Hicham. Assembling temperature sensors: thermocouples and resistance temperature detectors RTD (Pt100). Department of the Built Environment, Aalborg University, December 2020. http://dx.doi.org/10.54337/aau449755797.

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Temperature is one of the most common physical quantities (measurand) to be measured in experimental investigations, monitoring and control of building indoor environment, thermal comfort and building energy performance. The most common temperature sensors are the thermocouples and the resistance temperature detectors (RTDs). These analog sensors are cheap, accurate, durable and easy to replace or to repair. The cable of these sensors can easily be shortened or extended. These sensors have a simple, monotonic and stable correlation between the sensor’s temperature and their resistance/voltage output, which makes them ideal for temperature measurement with electronic logging equipment. This technical report aims at providing clear guidelines about how to assemble and mount type-K thermocouples and Pt100 RTDs. These are the most common temperature sensors used in the Laboratory of Building Energy and Indoor Environment at the Department of the Built Environment of Aalborg University.

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Liu, X., Z. Chen, and S. E. Grasby. Using shallow temperature measurements to evaluate thermal flux anomalies in the southern Mount Meager volcanic area, British Columbia, Canada. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330009.

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Geothermal is a clean and renewable energy resource. However, locating where elevated thermal gradient anomalies exist is a significant challenge when trying to assess potential resource volumes during early exploration of a prospective geothermal area. In this study, we deployed 22 temperature probes in the shallow subsurface along the south flank of the Mount Meager volcanic complex, to measure the transient temperature variation from September 2020 to August 2021. In our data analysis, a novel approach was developed to estimate the near-surface thermal distribution, and a workflow and code with python language have been completed for the thermal data pre-processing and analysis. The long-term temperature variation at different depths can be estimated by modelling, so that the relative difference of deducing deeper geothermal gradient anomalies can be assessed. Our proposed inversion and simulation methods were applied to calculating the temperature variation at 2.0 meters depth. The results identified a preferred high thermal flux anomalous zone in the south Mount Meager area. By combining with previous studies, the direct analysis and estimation of anomalous thermal fields based on the collected temperature data can provide a significant reference for interpretation of the regional thermal gradient variation.

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Friedman, Shmuel, Jon Wraith, and Dani Or. Geometrical Considerations and Interfacial Processes Affecting Electromagnetic Measurement of Soil Water Content by TDR and Remote Sensing Methods. United States Department of Agriculture, 2002. http://dx.doi.org/10.32747/2002.7580679.bard.

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Time Domain Reflectometry (TDR) and other in-situ and remote sensing dielectric methods for determining the soil water content had become standard in both research and practice in the last two decades. Limitations of existing dielectric methods in some soils, and introduction of new agricultural measurement devices or approaches based on soil dielectric properties mandate improved understanding of the relationship between the measured effective permittivity (dielectric constant) and the soil water content. Mounting evidence indicates that consideration must be given not only to the volume fractions of soil constituents, as most mixing models assume, but also to soil attributes and ambient temperature in order to reduce errors in interpreting measured effective permittivities. The major objective of the present research project was to investigate the effects of the soil geometrical attributes and interfacial processes (bound water) on the effective permittivity of the soil, and to develop a theoretical frame for improved, soil-specific effective permittivity- water content calibration curves, which are based on easily attainable soil properties. After initializing the experimental investigation of the effective permittivity - water content relationship, we realized that the first step for water content determination by the Time Domain Reflectometry (TDR) method, namely, the TDR measurement of the soil effective permittivity still requires standardization and improvement, and we also made more efforts than originally planned towards this objective. The findings of the BARD project, related to these two consequential steps involved in TDR measurement of the soil water content, are expected to improve the accuracy of soil water content determination by existing in-situ and remote sensing dielectric methods and to help evaluate new water content sensors based on soil electrical properties. A more precise water content determination is expected to result in reduced irrigation levels, a matter which is beneficial first to American and Israeli farmers, and also to hydrologists and environmentalists dealing with production and assessment of contamination hazards of this progressively more precious natural resource. The improved understanding of the way the soil geometrical attributes affect its effective permittivity is expected to contribute to our understanding and predicting capability of other, related soil transport properties such as electrical and thermal conductivity, and diffusion coefficients of solutes and gas molecules. In addition, to the originally planned research activities we also investigated other related problems and made many contributions of short and longer terms benefits. These efforts include: Developing a method and a special TDR probe for using TDR systems to determine also the soil's matric potential; Developing a methodology for utilizing the thermodielectric effect, namely, the variation of the soil's effective permittivity with temperature, to evaluate its specific surface area; Developing a simple method for characterizing particle shape by measuring the repose angle of a granular material avalanching in water; Measurements and characterization of the pore scale, saturation degree - dependent anisotropy factor for electrical and hydraulic conductivities; Studying the dielectric properties of cereal grains towards improved determination of their water content. A reliable evaluation of the soil textural attributes (e.g. the specific surface area mentioned above) and its water content is essential for intensive irrigation and fertilization processes and within extensive precision agriculture management. The findings of the present research project are expected to improve the determination of cereal grain water content by on-line dielectric methods. A precise evaluation of grain water content is essential for pricing and evaluation of drying-before-storage requirements, issues involving energy savings and commercial aspects of major economic importance to the American agriculture. The results and methodologies developed within the above mentioned side studies are expected to be beneficial to also other industrial and environmental practices requiring the water content determination and characterization of granular materials.

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Douglas, Thomas, Merritt Turetsky, and Charles Koven. Increased rainfall stimulates permafrost thaw across a variety of Interior Alaskan boreal ecosystems. Engineer Research and Development Center (U.S.), June 2021. http://dx.doi.org/10.21079/11681/41050.

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Earth’s high latitudes are projected to experience warmer and wetter summers in the future but ramifications for soil thermal processes and permafrost thaw are poorly understood. Here we present 2750 end of summer thaw depths representing a range of vegetation characteristics in Interior Alaska measured over a 5-year period. This included the top and third wettest summers in the 91-year record and three summers with precipitation close to mean historical values. Increased rainfall led to deeper thaw across all sites with an increase of 0.7 ± 0.1 cm of thaw per cm of additional rain. Disturbed and wetland sites were the most vulnerable to rain-induced thaw with ~1 cm of surface thaw per additional 1 cm of rain. Permafrost in tussock tundra, mixed forest, and conifer forest was less sensitive to rain-induced thaw. A simple energy budget model yields seasonal thaw values smaller than the linear regression of our measurements but provides a first-order estimate of the role of rain-driven sensible heat fluxes in high-latitude terrestrial permafrost. This study demonstrates substantial permafrost thaw from the projected increasing summer precipitation across most of the Arctic region.

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Wallace, Sean, Scott Lux, Constandinos Mitsingas, Irene Andsager, and Tapan Patel. Performance testing and modeling of a transpired ventilation preheat solar wall : performance evaluation of facilities at Fort Drum, NY, and Kansas Air National Guard, Topeka, KS. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/42000.

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This work performed measurement and verification of installed, operational solar wall systems at Fort Drum, NY, and Forbes Field, Air National Guard, Topeka, KS. Actual annual savings were compared estimated savings generated by a solar wall modeling tool (RETScreen). A comparison with the RETScreen modeling tool shows that the measured actively heated air provided by the solar wall provides 57% more heat than the RETScreen tool predicted, after accounting for boiler efficiency. The solar wall at Fort Drum yields a net savings of $851/yr, for a simple payback of 146 years and a SIR of 0.16. RETScreen models indicate that the solar wall system at Forbes Field, Kansas Air National Guard, Topeka, KS saves $9,350/yr, for a simple payback of 58.8 years and a SIR of 0.34. Although results showed that, due to low natural gas prices, the Fort Drum system was not economically viable, it was recommended that the system still be used to meet renewable energy and fossil fuel reduction goals. The current system becomes economical (SIR 1.00) at a natural gas rate of $16.00/MMBTU or $1.60 /therm.

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