E. Georgin | CETIAT - Academia.edu (original) (raw)

Papers by E. Georgin

Measurement

Abstract Gas-Controlled Heat Pipes (GCHPs) are devices based on generating and maintaining, at mi... more Abstract Gas-Controlled Heat Pipes (GCHPs) are devices based on generating and maintaining, at millikelvin level, a thermodynamic liquid-vapour equilibrium of a fluid. For this reason, GCHPs have been studied for more than thirty years for research and applications in thermal metrology. Capabilities have been constantly improved and adapted by National Metrology Institutes (NMIs) and accredited laboratories. Activities include study of vapour pressure curves of pure elements and substances, thermometers’ non-uniqueness up to 960 °C, calibrations between −20 °C and 900 °C with millikelvin uncertainties, studies of innovative pressure controllers allowing regulation better than 10−6 from below 1000 Pa up to 400 kPa. GCHPs operating at different temperature ranges have also been connected to a common pressure line in the so-called “Temperature Amplifier” configuration. This review paper presents an almost complete report about the several models of GCHPs, materials and working fluids, techniques adopted in different temperature/pressure ranges. All involved NMIs using GCHP are here included, with detailed bibliography.

18th International Congress of Metrology

Journal of Physics Communications

International Journal of Thermophysics

Moisture content can affect the thermo-physical properties of many materials. Thus sufficient kno... more Moisture content can affect the thermo-physical properties of many materials. Thus sufficient knowledge of this parameter is required to improve product shelf life and quality, reduce waste or enhance process efficiency. The traditional loss on drying methods are still the go-to methods due to their robustness and simplicity. However, their inherent lack of selectivity imposes restrictions. These are overcome with newer techniques such as vaporization coulometric Karl Fischer titration (vap-C-KFT) and evolved water vapor analysis (EWV). The former is a well-established method, but the latter was more recently introduced and the literature available on it is scarce. This work aims to bridge this gap in knowledge and demonstrate the comparability of the EWV to the more established vap-C-KFT. Multiple samples were studied and the data are analyzed along the principles reported recently by INRiM with a few modifications.

Measurement Science and Technology

International Journal of Thermophysics

International Journal of Thermophysics

CETIAT’s calibration laboratory, accredited by COFRAC, is a secondary thermometry laboratory. It ... more CETIAT’s calibration laboratory, accredited by COFRAC, is a secondary thermometry laboratory. It uses overflow and stirred calibration baths (\hbox {from} -\,80\,{^{\circ }}\hbox {C} \hbox { up } \hbox { to } +\,215\,{^{\circ }}\hbox {C})$$(from-80∘C upto+215∘C), dry blocks and furnaces (\hbox {from } +\,100\,{^{\circ }}\hbox {C} \hbox { up } \hbox { to } +\,1050\,{^{\circ }}\hbox {C})$$(from+100∘C upto+1050∘C) and thermostatic chambers (\hbox {from } -\,30\,{^{\circ }}\hbox {C} \hbox { up } \hbox { to } +\,160\,{^{\circ }}\hbox {C})$$(from-30∘C upto+160∘C). Typical calibration uncertainties that can be reached for platinum resistance thermometers in a thermostatic bath are between 0.03\,{^{\circ }}\hbox {C}$$0.03∘C and 0.06\,{^{\circ }}\hbox {C}$$0.06∘C. In order to improve its calibration capabilities, CETIAT is working on the implementation of a gas-controlled heat pipe (GCHP) temperature generator, used for industrial sensor calibrations. This article presents the results obtained during the characterization of water GCHP for industrial applications. This is a new approach to the use of a heat pipe as a temperature generator for industrial sensor calibrations. The objective of this work is to improve measurement uncertainties and daily productivity. Indeed, as has been shown in many studies (Dunn and Reay in Heat Pipes, Pergamon Press, Oxford, 1976; Merlone et al. 2012), the temperature of the system is pressure dependent and the response time, in temperature, follows the pressure accordingly. Thanks to this generator, it is possible to perform faster calibrations with smaller uncertainties. In collaboration with INRiM, the GCHP developed at CETIAT works with water and covers a temperature range from +\,30\,{^{\circ }}\hbox {C}$$+30∘C up to +\,150\,{^{\circ }}\hbox {C}$$+150∘C. This device includes some improvements such as a removable cover, which allows us to have different sets of thermometric wells adjustable according to the probe to be calibrated, and a pressure controller based on a temperature sensor. This article presents the metrological characterization in terms of homogeneity and stability in temperature. A rough investigation of the response time of the system is also presented in order to evaluate the time for reaching thermal equilibrium. The results obtained in this study concern stability and thermal homogeneity. The homogeneity on 200 mm is better than 5 mK and with a calibration uncertainty reduced by a factor of three.

Measurement Science and Technology

Launched in 2011 within the European Metrology Research Programme (EMRP) of EURAMET, the joint re... more Launched in 2011 within the European Metrology Research Programme (EMRP) of EURAMET, the joint research project "MeteoMet"-Metrology for Meteorology-is the largest EMRP consortium: National Metrology Institutes, Universities, meteorological and climate agencies, Research Institutes, collaborators and manufacturers are working together, developing new metrological techniques, as well as improving already existing ones, for meteorological observations and climate records. The project focuses on: humidity in the upper and surface atmosphere, air temperature, surface and deep-sea temperatures, soil moisture, salinity, permafrost temperature, precipitation and snow albedo effect on air temperature. All tasks are performed under rigorous metrological approach and include design and study of new sensors, new calibration facilities, investigation of sensors characteristics, improved techniques for measurements of Essential Climate Variables with uncertainty evaluation, traceability, laboratory proficiency and inclusion of field influencing parameters, long-lasting measurements, and campaigns in remote and extreme areas. MeteoMet vision is to make a further step towards establishing full data comparability, coherency, consistency and long-term continuity, through a comprehensive evaluation of the measurement uncertainties for the quantities involved in the global climate observing systems and the derived observations. The improvement of quality of Essential Climate Variables records, through the inclusion of measurement uncertainty budgets, will also highlight possible strategies for the reduction of the uncertainty. This contribution presents selected highlights of the MeteoMet project and reviews the main ongoing activities, tasks and deliverables, with a view to its possible future evolution and extended impact.

International Journal of Thermophysics

In order to improve the efficiency of moisture meters calibrations, we studied the effect of ambi... more In order to improve the efficiency of moisture meters calibrations, we studied the effect of ambient humidity, sample handling, packing and transportation on the timber wood (spruce) moisture determination. It was proved by experiments that dry timber samples ($$12 \times 12 \times 2.5$$12×12×2.5 cm) reach equilibrium within 30–40 days even when moisturizing them at a high relative air humidity (80 %). On the other hand, the major mass loss of moist samples placed at normal laboratory conditions was found to occur during the first few days while the first 5 days are critical. The effects of sample handling, packing and transportation were studied by means of interlaboratory comparison between CMI, CETIAT, INRIM, NIS and KRISS. The obtained results show that samples with moisture content less than 7 % tend to absorb small amount of water, whereas samples with moisture content larger than 15 % tend to desorb small amount of water during the handling and transporting even when using vacuum packing and short handling times.

Meteorological Applications, 2015

17th International Congress of Metrology, 2015

This is an Open Access article distributed under the terms of the Creative Commons Attribution Li... more This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

17th International Congress of Metrology, 2015

Le LNE-CETIAT fait partie d'un consortium, de laboratoires nationaux de métrologie, impliqué dans... more Le LNE-CETIAT fait partie d'un consortium, de laboratoires nationaux de métrologie, impliqué dans un projet européen de recherche en métrologie (Joint Research Project) dénommé SIB64 METefnet (www.metef.net) et financé par le comité European Metrology Research Programme (EMRP). L'objectif du projet est de permettre aux utilisateurs finaux de réaliser des mesures d'humidité dans les solides, fiables et traçables au SI, en améliorant les techniques de mesure et les méthodes d'étalonnage [1]. Parmi les différentes approches suivies par les partenaires de ce projet, le LNE-CETIAT a choisi de se concentrer sur la dissémination de la traçabilité au SI, à l'endroit d'utilisateurs industriels, en développement un instrument de transfert non destructif utilisant des Hautes-Fréquences et des micro-ondes, à bas niveau d'énergie (0dBm), pour mesurer l'humidité dans les matériaux solides. La fréquence de relaxation de l'eau dans un matériau dépend, notamment, du degré de liaison entre les molécules d'eau et la matrice solide (substrat) [2-3]. La bande de fréquences couvre un spectre qui s'étend des Hautes-Fréquences-HF, soit de quelques MHz à quelques centaines de MHz, aux Micro-Ondes-MO, soit de quelques centaines de MHz à quelques GHz. Ainsi, il est communément considéré, par les constructeurs utilisant les ondes électro-magnétiques-OEM comme moyen de chauffage dans les procédés de séchage, que l'eau liée physiquement ou chimiquement, à la matrice solide, interagit principalement et sélectivement avec les ondes du domaine RF, tandis que l'eau libre, dans la matrice solide, interagit principalement avec les MO (10 GHz). L'instrument développé dans le cadre de ce projet exploite cette sélectivité, vis-à-vis du type d'OEM utilisée, en faisant des mesures de propriétés diélectriques des matériaux humides. Ce principe de mesure est connu et utilisé depuis les années 70, les instruments alors développés fonctionnant exclusivement soit en RF soit en MO et sur bande de fréquence extrêmement étroite. Ces appareils ne permettent donc pas de couvrir une large gamme de fréquence de sorte à optimiser la fréquence de mesure vis-à-vis du degré de liaison de l'eau avec la matrice solide. L'originalité de ce travail repose sur la mise au point d'un instrument de mesure dont la fréquence de travail, utilisée pour mesurer l'humidité dans une matrice solide, est optimisée vis-à-vis de degré de liaison de l'eau avec le substrat et vis-à-vis de l'interaction entre l'OEM et le matériau. Pour ce faire, plus la fréquence de travail du capteur sera proche de la fréquence de relaxation mesurée plus la sensibilité de l'instrument sera bonne. Afin de déterminer la fréquence de relaxation de l'eau dans un solide, le CETIAT développe un équipement qui permet de couvrir une gamme de fréquences la plus grande possible. Pour ce besoin, deux cellules, non-résonnantes, ont été développées : une cellule capacitive et une cellule coaxiale. Cet article présente les cellules développées ainsi que les premiers résultats expérimentaux obtenus avec la cellule capacitive.

17th International Congress of Metrology, 2015

17th International Congress of Metrology, 2015

17th International Congress of Metrology, 2015

In the framework of the European research project MeteoMet, the LNE-CNAM and the LNE-CETIAT are d... more In the framework of the European research project MeteoMet, the LNE-CNAM and the LNE-CETIAT are developing novel copper cells for the determination of the water vapour pressure equation and the measurement of the triple point of water temperature at the highest degree of accuracy. The Water Vapour Pressure Equation (WVPE) is the basic formula for the calculation of the vapour pressure and other humidity related quantities. Improvement in the uncertainty of the water vapour formulation in the temperature range between -80^{\cdot}C (and possibly down to -90^{\cdot}C) and +100^{\cdot}C is needed for the improvement of primary standards in the field of hygrometry. The Triple Point of Water (TPW, temperature 273,16 K) plays a key role in thermometry, because of its threefold function. On one side, it defines the temperature unit, the kelvin. On the other side, it is the reference point in Standard Platinum Resistance Thermometer (SPRT) calibrations, according to the International Tempera...

16th International Congress of Metrology, 2013

The thermal time constant of a homogeneous body is a parameter currently used for studying the dy... more The thermal time constant of a homogeneous body is a parameter currently used for studying the dynamic of heating and cooling processes. In case of natural or forced convection, its model structure is defined by the product of independent parameters affected by a specific dispersion. The thermal time constant uncertainty results from the propagation of parametric uncertainties through this model. We propose to estimate analytically this uncertainty by using parameter distributions adapted to the multiplicative structure of the model. The methodology is illustrated by a numerical application relative to the two previous convective processes. Résumé. La constante de temps thermique d'un corps homogène est un paramètre couramment utilisé pour l'étude dynamique des processus d'échauffement et de refroidissement. Dans les cas de transferts par convection naturelle ou forcée, la structure de son modèle est définie par le produit de paramètres indépendants, affectés d'une dispersion spécifique. L'incertitude de la constante de temps thermique résulte de la propagation à travers ce modèle des incertitudes paramétriques. Nous proposons d'estimer analytiquement cette incertitude en utilisant des distributions paramétriques adaptées à la structure multiplicative du modèle. La méthodologie est illustrée par une application numérique concernant les deux cas de transfert convectif. 201 / 315012 16 th metrology International Congress of Metrology, 15012 (2013) This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2 0 , which. permits unrestricted use, distributi and reproduction in any medium, provided the original work is properly cited.

International Journal of Thermophysics, 2015

ABSTRACT Measurement of moisture in materials presents many challenges, due to diverse measuring ... more ABSTRACT Measurement of moisture in materials presents many challenges, due to diverse measuring principles, sample interactions with atmosphere, and variation in what is measured (either water content alone or moisture including other liquids). Calibrations are variously referenced to published standard methods, primary calibration facilities, or certified reference materials, but each of these addresses limited substances and ranges of measurement. Overall, metrology infrastructure is not as fully developed or coherent for this field as it is for many other areas of measurement. In order to understand the metrology needs and to support developments, several European national metrology institutes (NMIs) have undertaken some collaborative activities. These have included a “cooperation in research” project for sharing of information, a survey of moisture capabilities at NMIs, the formulation of a strategy for moisture metrology at the NMI level, and a funded research project to develop improved metrology for the moisture field. This paper summarizes the information gathered, giving an overview of the status of moisture metrology at NMIs, and it reports a proposed strategy to improve the current situation.

Measurement

Abstract Gas-Controlled Heat Pipes (GCHPs) are devices based on generating and maintaining, at mi... more Abstract Gas-Controlled Heat Pipes (GCHPs) are devices based on generating and maintaining, at millikelvin level, a thermodynamic liquid-vapour equilibrium of a fluid. For this reason, GCHPs have been studied for more than thirty years for research and applications in thermal metrology. Capabilities have been constantly improved and adapted by National Metrology Institutes (NMIs) and accredited laboratories. Activities include study of vapour pressure curves of pure elements and substances, thermometers’ non-uniqueness up to 960 °C, calibrations between −20 °C and 900 °C with millikelvin uncertainties, studies of innovative pressure controllers allowing regulation better than 10−6 from below 1000 Pa up to 400 kPa. GCHPs operating at different temperature ranges have also been connected to a common pressure line in the so-called “Temperature Amplifier” configuration. This review paper presents an almost complete report about the several models of GCHPs, materials and working fluids, techniques adopted in different temperature/pressure ranges. All involved NMIs using GCHP are here included, with detailed bibliography.

18th International Congress of Metrology

Journal of Physics Communications

International Journal of Thermophysics

Moisture content can affect the thermo-physical properties of many materials. Thus sufficient kno... more Moisture content can affect the thermo-physical properties of many materials. Thus sufficient knowledge of this parameter is required to improve product shelf life and quality, reduce waste or enhance process efficiency. The traditional loss on drying methods are still the go-to methods due to their robustness and simplicity. However, their inherent lack of selectivity imposes restrictions. These are overcome with newer techniques such as vaporization coulometric Karl Fischer titration (vap-C-KFT) and evolved water vapor analysis (EWV). The former is a well-established method, but the latter was more recently introduced and the literature available on it is scarce. This work aims to bridge this gap in knowledge and demonstrate the comparability of the EWV to the more established vap-C-KFT. Multiple samples were studied and the data are analyzed along the principles reported recently by INRiM with a few modifications.

Measurement Science and Technology

International Journal of Thermophysics

International Journal of Thermophysics

CETIAT’s calibration laboratory, accredited by COFRAC, is a secondary thermometry laboratory. It ... more CETIAT’s calibration laboratory, accredited by COFRAC, is a secondary thermometry laboratory. It uses overflow and stirred calibration baths (\hbox {from} -\,80\,{^{\circ }}\hbox {C} \hbox { up } \hbox { to } +\,215\,{^{\circ }}\hbox {C})$$(from-80∘C upto+215∘C), dry blocks and furnaces (\hbox {from } +\,100\,{^{\circ }}\hbox {C} \hbox { up } \hbox { to } +\,1050\,{^{\circ }}\hbox {C})$$(from+100∘C upto+1050∘C) and thermostatic chambers (\hbox {from } -\,30\,{^{\circ }}\hbox {C} \hbox { up } \hbox { to } +\,160\,{^{\circ }}\hbox {C})$$(from-30∘C upto+160∘C). Typical calibration uncertainties that can be reached for platinum resistance thermometers in a thermostatic bath are between 0.03\,{^{\circ }}\hbox {C}$$0.03∘C and 0.06\,{^{\circ }}\hbox {C}$$0.06∘C. In order to improve its calibration capabilities, CETIAT is working on the implementation of a gas-controlled heat pipe (GCHP) temperature generator, used for industrial sensor calibrations. This article presents the results obtained during the characterization of water GCHP for industrial applications. This is a new approach to the use of a heat pipe as a temperature generator for industrial sensor calibrations. The objective of this work is to improve measurement uncertainties and daily productivity. Indeed, as has been shown in many studies (Dunn and Reay in Heat Pipes, Pergamon Press, Oxford, 1976; Merlone et al. 2012), the temperature of the system is pressure dependent and the response time, in temperature, follows the pressure accordingly. Thanks to this generator, it is possible to perform faster calibrations with smaller uncertainties. In collaboration with INRiM, the GCHP developed at CETIAT works with water and covers a temperature range from +\,30\,{^{\circ }}\hbox {C}$$+30∘C up to +\,150\,{^{\circ }}\hbox {C}$$+150∘C. This device includes some improvements such as a removable cover, which allows us to have different sets of thermometric wells adjustable according to the probe to be calibrated, and a pressure controller based on a temperature sensor. This article presents the metrological characterization in terms of homogeneity and stability in temperature. A rough investigation of the response time of the system is also presented in order to evaluate the time for reaching thermal equilibrium. The results obtained in this study concern stability and thermal homogeneity. The homogeneity on 200 mm is better than 5 mK and with a calibration uncertainty reduced by a factor of three.

Measurement Science and Technology

Launched in 2011 within the European Metrology Research Programme (EMRP) of EURAMET, the joint re... more Launched in 2011 within the European Metrology Research Programme (EMRP) of EURAMET, the joint research project "MeteoMet"-Metrology for Meteorology-is the largest EMRP consortium: National Metrology Institutes, Universities, meteorological and climate agencies, Research Institutes, collaborators and manufacturers are working together, developing new metrological techniques, as well as improving already existing ones, for meteorological observations and climate records. The project focuses on: humidity in the upper and surface atmosphere, air temperature, surface and deep-sea temperatures, soil moisture, salinity, permafrost temperature, precipitation and snow albedo effect on air temperature. All tasks are performed under rigorous metrological approach and include design and study of new sensors, new calibration facilities, investigation of sensors characteristics, improved techniques for measurements of Essential Climate Variables with uncertainty evaluation, traceability, laboratory proficiency and inclusion of field influencing parameters, long-lasting measurements, and campaigns in remote and extreme areas. MeteoMet vision is to make a further step towards establishing full data comparability, coherency, consistency and long-term continuity, through a comprehensive evaluation of the measurement uncertainties for the quantities involved in the global climate observing systems and the derived observations. The improvement of quality of Essential Climate Variables records, through the inclusion of measurement uncertainty budgets, will also highlight possible strategies for the reduction of the uncertainty. This contribution presents selected highlights of the MeteoMet project and reviews the main ongoing activities, tasks and deliverables, with a view to its possible future evolution and extended impact.

International Journal of Thermophysics

In order to improve the efficiency of moisture meters calibrations, we studied the effect of ambi... more In order to improve the efficiency of moisture meters calibrations, we studied the effect of ambient humidity, sample handling, packing and transportation on the timber wood (spruce) moisture determination. It was proved by experiments that dry timber samples ($$12 \times 12 \times 2.5$$12×12×2.5 cm) reach equilibrium within 30–40 days even when moisturizing them at a high relative air humidity (80 %). On the other hand, the major mass loss of moist samples placed at normal laboratory conditions was found to occur during the first few days while the first 5 days are critical. The effects of sample handling, packing and transportation were studied by means of interlaboratory comparison between CMI, CETIAT, INRIM, NIS and KRISS. The obtained results show that samples with moisture content less than 7 % tend to absorb small amount of water, whereas samples with moisture content larger than 15 % tend to desorb small amount of water during the handling and transporting even when using vacuum packing and short handling times.

Meteorological Applications, 2015

17th International Congress of Metrology, 2015

This is an Open Access article distributed under the terms of the Creative Commons Attribution Li... more This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

17th International Congress of Metrology, 2015

Le LNE-CETIAT fait partie d'un consortium, de laboratoires nationaux de métrologie, impliqué dans... more Le LNE-CETIAT fait partie d'un consortium, de laboratoires nationaux de métrologie, impliqué dans un projet européen de recherche en métrologie (Joint Research Project) dénommé SIB64 METefnet (www.metef.net) et financé par le comité European Metrology Research Programme (EMRP). L'objectif du projet est de permettre aux utilisateurs finaux de réaliser des mesures d'humidité dans les solides, fiables et traçables au SI, en améliorant les techniques de mesure et les méthodes d'étalonnage [1]. Parmi les différentes approches suivies par les partenaires de ce projet, le LNE-CETIAT a choisi de se concentrer sur la dissémination de la traçabilité au SI, à l'endroit d'utilisateurs industriels, en développement un instrument de transfert non destructif utilisant des Hautes-Fréquences et des micro-ondes, à bas niveau d'énergie (0dBm), pour mesurer l'humidité dans les matériaux solides. La fréquence de relaxation de l'eau dans un matériau dépend, notamment, du degré de liaison entre les molécules d'eau et la matrice solide (substrat) [2-3]. La bande de fréquences couvre un spectre qui s'étend des Hautes-Fréquences-HF, soit de quelques MHz à quelques centaines de MHz, aux Micro-Ondes-MO, soit de quelques centaines de MHz à quelques GHz. Ainsi, il est communément considéré, par les constructeurs utilisant les ondes électro-magnétiques-OEM comme moyen de chauffage dans les procédés de séchage, que l'eau liée physiquement ou chimiquement, à la matrice solide, interagit principalement et sélectivement avec les ondes du domaine RF, tandis que l'eau libre, dans la matrice solide, interagit principalement avec les MO (10 GHz). L'instrument développé dans le cadre de ce projet exploite cette sélectivité, vis-à-vis du type d'OEM utilisée, en faisant des mesures de propriétés diélectriques des matériaux humides. Ce principe de mesure est connu et utilisé depuis les années 70, les instruments alors développés fonctionnant exclusivement soit en RF soit en MO et sur bande de fréquence extrêmement étroite. Ces appareils ne permettent donc pas de couvrir une large gamme de fréquence de sorte à optimiser la fréquence de mesure vis-à-vis du degré de liaison de l'eau avec la matrice solide. L'originalité de ce travail repose sur la mise au point d'un instrument de mesure dont la fréquence de travail, utilisée pour mesurer l'humidité dans une matrice solide, est optimisée vis-à-vis de degré de liaison de l'eau avec le substrat et vis-à-vis de l'interaction entre l'OEM et le matériau. Pour ce faire, plus la fréquence de travail du capteur sera proche de la fréquence de relaxation mesurée plus la sensibilité de l'instrument sera bonne. Afin de déterminer la fréquence de relaxation de l'eau dans un solide, le CETIAT développe un équipement qui permet de couvrir une gamme de fréquences la plus grande possible. Pour ce besoin, deux cellules, non-résonnantes, ont été développées : une cellule capacitive et une cellule coaxiale. Cet article présente les cellules développées ainsi que les premiers résultats expérimentaux obtenus avec la cellule capacitive.

17th International Congress of Metrology, 2015

17th International Congress of Metrology, 2015

17th International Congress of Metrology, 2015

In the framework of the European research project MeteoMet, the LNE-CNAM and the LNE-CETIAT are d... more In the framework of the European research project MeteoMet, the LNE-CNAM and the LNE-CETIAT are developing novel copper cells for the determination of the water vapour pressure equation and the measurement of the triple point of water temperature at the highest degree of accuracy. The Water Vapour Pressure Equation (WVPE) is the basic formula for the calculation of the vapour pressure and other humidity related quantities. Improvement in the uncertainty of the water vapour formulation in the temperature range between -80^{\cdot}C (and possibly down to -90^{\cdot}C) and +100^{\cdot}C is needed for the improvement of primary standards in the field of hygrometry. The Triple Point of Water (TPW, temperature 273,16 K) plays a key role in thermometry, because of its threefold function. On one side, it defines the temperature unit, the kelvin. On the other side, it is the reference point in Standard Platinum Resistance Thermometer (SPRT) calibrations, according to the International Tempera...

16th International Congress of Metrology, 2013

The thermal time constant of a homogeneous body is a parameter currently used for studying the dy... more The thermal time constant of a homogeneous body is a parameter currently used for studying the dynamic of heating and cooling processes. In case of natural or forced convection, its model structure is defined by the product of independent parameters affected by a specific dispersion. The thermal time constant uncertainty results from the propagation of parametric uncertainties through this model. We propose to estimate analytically this uncertainty by using parameter distributions adapted to the multiplicative structure of the model. The methodology is illustrated by a numerical application relative to the two previous convective processes. Résumé. La constante de temps thermique d'un corps homogène est un paramètre couramment utilisé pour l'étude dynamique des processus d'échauffement et de refroidissement. Dans les cas de transferts par convection naturelle ou forcée, la structure de son modèle est définie par le produit de paramètres indépendants, affectés d'une dispersion spécifique. L'incertitude de la constante de temps thermique résulte de la propagation à travers ce modèle des incertitudes paramétriques. Nous proposons d'estimer analytiquement cette incertitude en utilisant des distributions paramétriques adaptées à la structure multiplicative du modèle. La méthodologie est illustrée par une application numérique concernant les deux cas de transfert convectif. 201 / 315012 16 th metrology International Congress of Metrology, 15012 (2013) This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2 0 , which. permits unrestricted use, distributi and reproduction in any medium, provided the original work is properly cited.

International Journal of Thermophysics, 2015

ABSTRACT Measurement of moisture in materials presents many challenges, due to diverse measuring ... more ABSTRACT Measurement of moisture in materials presents many challenges, due to diverse measuring principles, sample interactions with atmosphere, and variation in what is measured (either water content alone or moisture including other liquids). Calibrations are variously referenced to published standard methods, primary calibration facilities, or certified reference materials, but each of these addresses limited substances and ranges of measurement. Overall, metrology infrastructure is not as fully developed or coherent for this field as it is for many other areas of measurement. In order to understand the metrology needs and to support developments, several European national metrology institutes (NMIs) have undertaken some collaborative activities. These have included a “cooperation in research” project for sharing of information, a survey of moisture capabilities at NMIs, the formulation of a strategy for moisture metrology at the NMI level, and a funded research project to develop improved metrology for the moisture field. This paper summarizes the information gathered, giving an overview of the status of moisture metrology at NMIs, and it reports a proposed strategy to improve the current situation.