TY - CHAP A1 - Hartmann, Jürgen A1 - Taubert, Dieter Richard A1 - Anhalt, Klaus A1 - Gutschwager, B. A1 - Monte, C. A1 - Hollandt, Jörg T1 - Radiation thermometry, thermodynamic temperature and emissivity measurements at the PTB BT - an overview N2 - To meet the increasing demand of calibrations in the field of radiation thermometry, the Physikalisch-Technische Bundesanstalt (PTB) operates two different setups for calibrations covering the temperature range from-60 C up to 3000 C. The first setup consists of several heat-pipe blackbodies in conjunction with platinum resistance thermometers, calibrated according to the International Temperature Scale of 1990 (ITS-90) and is applied for calibrations in the temperature range from-60 C to 961.78 C. In the temperature range from 962 C to 3000 C the calibration is based on high temperature blackbodies. The temperature of these blackbodies is determined in two independent ways: traceable to the ITS-90 gold fixed point or via absolutely calibrated filter radiometers (FR) traceable to the detector primary standard, the cryogenic radiometer. Taking advantage from the high accuracy of the FR calibration, these FRs have also been successfully used for the investigation of the thermodynamic accuracy of the ITS-90 in the range from 419 C to 962 C. For non-contact temperature measurements, the emissivity of the observed object is one of the most important parameters. Therefore, PTB has set up instrumentations for measuring the directional spectral and total emissivity of samples in air from 80 C up to 400 C over a spectral range from 4 µm to 40 µm and under vacuum from 0 C to 600 C and in the spectral range from 1 µm to 1000 µm. Y1 - 2009 UR - http://www.cenam.mx/dme/pdf/EXT_A-Vie-1.pdf PB - Encuentro Nacional de Metrología Eléctrica 2009 CY - Queretaro (Mexico) ER - TY - JOUR A1 - Hartmann, Jürgen A1 - Machin, Graham A1 - Bloembergen, P A1 - Anhalt, Klaus A1 - Sadli, M A1 - Saunders, P A1 - Wooliams, E A1 - Yamada, Y A1 - Yoon, H T1 - Practical Implementation of the Mise en Pratique for the Definition of the Kelvin Above the Silver Point JF - International Journal of Thermophysics N2 - The “Mise en pratique for the definition of the kelvin” (MeP-K) was established in April 2006 to be the repository of information required to perform a “practical measurement of temperature in accordance with the International System of Units (SI).” This article describes the progress made by the MeP-K HT (High Temperature Task Group) of CCT-WG5 (radiation thermometry) in drawing together the appropriate methods for accessing thermodynamic temperature above the silver point involving direct radiometric measurements on the one hand and indirect extrapolation, interpolation, and least-squares fitting on the other. An examination of the uncertainties and a brief discussion of the advantages and disadvantages of the various approaches are given. A summary of the remaining issues to be resolved concludes the article. Y1 - 2010 U6 - https://doi.org/10.1007/s10765-010-0834-5 VL - 31 IS - 8-9 SP - 1779 EP - 1788 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Bloembergen, P A1 - Yamada, Y A1 - Yamamoto, N T1 - Realizing the High‐Temperature Part of a Future ITS with the Aid of Eutectic Metal‐Carbon Fixed Points T2 - AIP Conference Proceedings (684) N2 - In the proposed scheme temperatures are defined by interpolation and extrapolation with respect to two reference fixed points (n=2), with assigned temperatures. The definition includes one full‐range and two sub‐ranges in temperature. The scheme in question will be compared with two alternatives referred to (1) as n=1, using one reference point only, as in the ITS‐90, and (2) as n=0, involving direct measurement of the thermodynamic temperature by means of absolute radiometry. Y1 - 2003 SN - 0-7354-0153-5 SP - 291 EP - 296 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Machin, G A1 - Beynon, G A1 - Edler, F A1 - Fourrez, S A1 - Lowe, D A1 - Morice, R A1 - Sadli, M A1 - Villamanan, M T1 - HIMERT BT - A pan‐European project for the development of metal‐carbon eutectics as temperature standards T2 - AIP Conference Proceedings N2 - Metal‐carbon eutectic mixtures show much promise for high‐temperature standards applications. A research project, Novel, High temperature, Metal‐carbon Eutectic fixed points for Radiation Thermometry, Radiometry and Thermocouples (HIMERT) was accepted by the European Union (submitted under the Framework 5 Growth Programme) with a view to developing a unified European approach to these standards. The objectives of the project are to develop fixed‐point cells both for radiation thermometry/radiometry and contact thermometry calibration applications. In total three sets of cells will be developed, two for radiation thermometry (by BNM‐INM and NPL) and one for contact sensors (by BNM‐LNE) and comparisons performed of the differing crucible designs. The cells developed for radiation thermometry will be calibrated according to the ITS‐90 and measured radiometrically by a third participant (PTB … Y1 - 2003 SN - 0-7354-0153-5 SP - 285 EP - 290 PB - American Institute of Physics ER - TY - JOUR A1 - Hartmann, Jürgen A1 - Manara, Jochen A1 - Zipf, Matthias A1 - Stark, Thomas A1 - Arduini, Mariacarla A1 - Ebert, Hans-Peter A1 - Tutschke, Andreas A1 - Hallam, Andrew A1 - Hanspal, Jagdevinder A1 - Langley, Mark A1 - Hodge, D. T1 - Long wavelength infrared radiation thermometry for non-contact temperature measurements in gas turbines JF - Infrared Physics & Technology N2 - The objective of the EU project “Sensors Towards Advanced Monitoring and Control of Gas Turbine Engines (acronym STARGATE)” is the development of a suite of advanced sensors, instrumentation and related systems in order to contribute to the developing of the next generation of green and efficient gas turbine engines. One work package of the project deals with the design and development of a long wavelength infrared (LWIR) radiation thermometer for the non-contact measurement of the surface temperature of thermal barrier coatings (TBCs) during the operation of gas turbine engines. For opaque surfaces (e.g. metals or superalloys) radiation thermometers which are sensitive in the near or short wavelength infrared are used as state-of-the-art method for non-contact temperature measurements. But this is not suitable for oxide ceramic based TBCs (e.g. partially yttria stabilized zirconia) as oxide ceramics … Y1 - 2017 UR - https://www.sciencedirect.com/science/article/pii/S1350449516303395 IS - 80 SP - 120 EP - 130 ER - TY - CHAP A1 - Hartmann, Jürgen T1 - Investigation of the Accuracy of the ITS‐90 with Reference to Thermodynamic Temperature in the Range from 400° C up to 600° C T2 - AIP Conference Proceedings (684) N2 - For several years Physikalisch‐Technische Bundesanstalt (PTB) has performed thermodynamic temperature measurements on a large area blackbody applying filter radiometers (FR) based on silicon photodiodes and interference filters with center wavelengths at 676 nm, 800 nm, 900 nm, and 1000 nm. These FRs were used for the determination of possible systematic deviations of temperatures measured according to the International Temperature Scale of 1990 (ITS‐90), T90, and the thermodynamic temperatures T. The measurements in 1995 with the 676‐nm‐FR and the 800‐nm‐FR revealed a difference of 50 mK of T−T90 at temperatures around the freezing point of silver (961.78 °C). The observed difference decreases with decreasing temperatures, indicating that it may be attributed to a systematic deviation in the ITS‐90 from T due to the gas thermometric temperature measurement at 457 °C, which has … Y1 - 2003 SN - 0-7354-0153-5 SP - 7 EP - 12 PB - American Institute of Physics ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Fischer, Joachim ED - Rozlonski, Andrés E. ED - Dinwiddie, Ralph B. T1 - Calibration and investigation of infrared camera systems applying blackbody radiation T2 - Thermosense XXIII N2 - An experimental facility is presented, which allows calibration and detailed investigation of infrared camera systems. Various blackbodies operating in the temperature range from -60 degree(s)C up to 3000 degree(s)C serve as standard radiation sources, enabling calibration of camera systems in a wide temperature and spectral range with highest accuracy. Quantitative results and precise long-term investigations, especially in detecting climatic trends, require accurate traceability to the International Temperature Scale of 1990 (ITS-90). For the used blackbodies the traceability to ITS- 90 is either realized by standard platinum resistance thermometers (in the temperature range below 962 degree(s)C) or by absolute and relative radiometry (in the temperature range above 962 degree(s)C). This traceability is fundamental for implementation of quality assurance systems and realization of different standardizations, for … Y1 - 2001 UR - https://www.spiedigitallibrary.org/conference-proceedings-of-spie/4360/0000/Calibration-and-investigation-of-infrared-camera-systems-applying-blackbody-radiation/10.1117/12.421018.short?SSO=1 IS - 4360 SP - 402 EP - 411 PB - International Society for Optics and Photonics - Proceedings of SPIE ER - TY - CHAP A1 - Hartmann, Jürgen T1 - Optimized strategies for thermal re-activation of LaF3/Pt-sensors based on photothermal characterization T2 - AIP Conference Proceedings (463) N2 - Gas sensors based on a semiconductor-supported LaF3/Pt-structure require regular re-activation by thermal treatment. A convenient way to accomplish this is by applying an electrical current pulse to the Pt-electrode and controlling re-activation by the amount of Joule heat deposited. Pulse length has to be chosen to balance the requirements of thermal energy needed for re-activation and the constraints in peak thermal power to prevent damage. Prerequisite to optimization is a knowledge of the thermal response of the complicated thin film sensor system consisting of several layers with unknown thermal properties. Modulated photothermal microscopy was used to detect inhomogenities in thin film heating and early stages of failure under thermal load. It was found that the formation of gas bubbles in the film is one of the major sources of failure. These measurements were complemented by measurements of … Y1 - 1999 SP - 398 EP - 400 PB - American Institute of Physics ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Moritz, W. A1 - Roth, U. A1 - Heyde, M. A1 - Rademann, K. A1 - Reichling, M. T1 - Nanosecond Range Heating and Temperature Measurement on Thin Layers BT - Experiment and Simulation T2 - Proceedings of the International Conference on Modeling and Simulation of Microsystems, Semiconductors, Sensors and Actuators N2 - A chemical semiconductor sensor for oxygen gas was activated by thermal treatment. The thin Pt layer of the n-Si/SiO2/Si3N4/LaF3/Pt field effect structure was used as the gate electrode for sensitivity measurements, heating resistance and temperature sensor. Taking advantage of using the gate electrode for heating only the sensitive two layer system LaF3/Pt (thickness only 300 nm) has to be at high temperature. The reactivation was shown to be a very fast process. Within a period of 10µs the structure was heated and the activation process was completed. The temperature measurement was done using the voltage drop at the gate and the current of the heating impulse. For the temperature measurement a resolution on the time scale of nanoseconds was achieved. The time dependent temperature distribution in the sensor multi layer structure was simulated using the CFD-ACE+ software of CFDRC. For the µs-impulses the temperature increase of only the thin layers and not the silicon bulk was shown. Y1 - 1999 UR - https://www.researchgate.net/profile/Juergen_Hartmann3/publication/238109507_Nanosecond_Range_Heating_and_Temperature_Measurement_on_Thin_Layers_Experiment_and_Simulation/links/0a85e52e8b51b9126e000000/Nanosecond-Range-Heating-and-Temperature-Measurement-on-Thin-Layers-Experiment-and-Simulation.pdf SP - 655 EP - 658 PB - MSM 99 ER - TY - JOUR A1 - Hartmann, Jürgen A1 - Zipf, Matthias A1 - Manara, Jochen A1 - Stark, Thomas A1 - Arduini, Mariacarla A1 - Ebert, Hans-Peter T1 - Identification of wavelength regions for non-contact temperature measurement of combustion gases at high temperatures and high pressures JF - High Temperatures – High Pressures N2 - Stationary gas turbines are still an important part of today's power supply. With increasing temperature of the hot combustion gas inside a gas turbine, the efficiency factor of the turbine increases. For this reason, it is intended to operate turbines at the highest possible gas temperature. Therefore, in the combustion chamber and especially at the position of the first stage guide vanes the gas temperature needs to be measured reliably. To determine the gas temperature, one promising approach is the application of a non-contact measurement method using a radiation thermometer. A radiation thermometer can measure the gas temperature remotely from outside of the harsh environment. At ZAE Bayern, a high temperature and high pressure gas cell has been developed for this purpose in order to investigate gases and gas mixtures under defined conditions at high pressures and high temperatures. This gas cell can … Y1 - 2020 VL - 49 IS - 3 SP - 241 EP - 260 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Zipf, Matthias A1 - Manara, Jochen A1 - Stark, Thomas A1 - Arduini, Mariacarla A1 - Ebert, Hans-Peter T1 - Berührungslose Temperaturmessung an Verbrennungsgasen bei hohen Temperaturen und hohen Drücken T2 - 20. GMA/ITG-Fachtagung Sensoren und Messsysteme 2019 N2 - Stationäre Gasturbinen sind von großer Bedeutung für die heutige Energieversorgung. Der Wirkungsgrad einer Gasturbine steigt mit zunehmender Heißgastemperatur an. Turbinenhersteller bzw. Kraftwerksbetreiber sind daher bestrebt, Turbinen bei der höchsten materialtechnisch möglichen Heißgastemperatur einzusetzen. Eine entsprechende Prozessoptimierung des Turbinenbetriebs setzt somit die exakte Kenntnis der Gastemperaturen während des Betriebs und damit eine verlässliche Messung derselben voraus. Zur Messung der Gastemperatur werden derzeit in der Regel Thermoelemente unmittelbar im Abgasstrom platziert. Aufgrund der dort vorherrschenden extremen Bedingungen degradieren diese Sensoren allerdings sehr schnell. Ein alternativer Ansatz sieht die Entwicklung eines berührungslosen Messverfahrens auf der Grundlage von Strahlungsthermometern vor. Für die Umsetzung dieses Vorhabens ist die genaue Kenntnis des Verhaltens der infrarot-optischen Emissions- und Transmissionsspektren der im Abgasstrom enthaltenen Gase bei hohen Temperaturen und Drücken eine wesentliche Voraussetzung. Aus diesem Grund wurde am ZAE Bayern eine Hochtemperatur-Hochdruck-Gaszelle entwickelt, die es in Verbindung mit einem FTIR-Spektrometer erlaubt, Gase und Gasgemische hinsichtlich dieser Gesichtspunkte zu charakterisieren. In dieser Arbeit wird die neue Messapparatur vorgestellt und Gasgemische, die für die Turbinenanwendungen relevant sind, werden analysiert. Zur Identifizierung eines geeigneten Wellenlängenbereichs für die geplante berührungslose Temperaturmessung wurden erste Messungen durchgeführt, auf deren Grundlage ein adäquater Wellenlängenbereich ermittelt werden konnte. Y1 - 2019 UR - 10.5162/sensoren2019/2.4.2 SN - 978-3-9819376-0-2 SP - 183 EP - 190 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Manara, Jochen A1 - Zipf, Matthias A1 - Stark, Thomas A1 - Knopp, Kevin A1 - Zänglein, Marc A1 - Schreiber, Ekkehard A1 - Schmidt, Franz A1 - Brunner, Martin A1 - Müller, Michael T1 - Experimental set-up for dynamic material investigation at high temperatures T2 - Sensors and Measuring Systems; 19th ITG/GMA-Symposium N2 - Energy efficiency and operation safety in energy conversion, process technology, and aerospace engineering requires advanced material investigation, in particular at high temperatures to characterize the materials and components. Additionally, modern additive manufacturing methods, in particular the 3D metal laser printer requires a detailed control of the melting temperature. Many applications are based on a layered structures, e.g. thermal barrier coatings in gas turbines. Also components manufactured by additive manufacturing pose a layered structure. In these structures the mechanical contact between the layers and to the substrate is of high interest. Besides, the complete characterisation of the additive manufactured component is important for its later application. To cope with these new demands, the University of Applied Sciences Wuerzburg - Schweinfurt (FHWS) and the Bavarian Center for Applied … Y1 - 2018 UR - https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=8436229 SN - 978-3-8007-4683-5 SP - 516 EP - 519 PB - VDE Verlag ER - TY - JOUR A1 - Hartmann, Jürgen A1 - Manara, Jochen A1 - Stark, Thomas A1 - Zipf, Matthias A1 - Arduini, Mariacarla A1 - Ebert, Hans-Peter A1 - Tutschke, Andreas A1 - Hallam, Andrew A1 - Hanspal, Jagdevinder A1 - Langley, Mark T1 - Entwicklung und Test eines langwelligen Strahlungsthermometers zur berührungslosen Temperaturmessung in Gasturbinen während des Betriebs JF - tm - Technisches Messen N2 - The aim of this work was the development of a long wavelength infrared radiation thermometer for the non-contact measurement of surface temperatures in stationary gas turbines during operation within the EU-project „Sensors Towards Advanced Monitoring and Control of Gas Turbine Engines (acronym STARGATE)“. In this work, the infrared-optical properties of the thermal barrier coatings and the combustion gases were determined at ZAE Bayern at high temperatures up to 1600 K and pressures up to 13 bar. Based on these experimental characterizations, a suitable spectral range could be identified which lies around 10 μm for the long-wavelength infrared radiation thermometer. According to these findings, a laboratory setup with suitable optical components (filters, IR-fibers, etc.) was firstly realized and verified. Subsequently, a prototype for measurements in gas turbines during operation of the turbines has … N2 - Das Ziel dieser Arbeit bestand in der Entwicklung eines langwelligen Strahlungsthermometers zur berührungslosen Messung von Oberflächentemperaturen in stationären Gasturbinen während des Betriebs der Turbinen innerhalb des EU-geförderten Projektes „Sensors Towards Advanced Monitoring and Control of Gas Turbine Engines (Acronym STARGATE)“. Im Rahmen der Arbeit wurden die infrarot-optischen Eigenschaften der Wärmedämmschichten und der vorhandenen Brenngase am ZAE Bayern bei hohen Temperaturen bis 1600 K und Drücken bis 13 bar bestimmt. Mit Hilfe dieser experimentellen Charakterisierungen konnte ein geeigneter Spektralbereich um 10 μm für das langwellige Strahlungsthermometer identifiziert werden. Entsprechend dieser Erkenntnisse wurde zunächst ein Laboraufbau mit geeigneten optischen Bauteilen (Filter, IR-Wellenleiter, etc.) realisiert und verifiziert. Anschließend wurde ein Prototyp für Messungen in Gasturbinen während des Betriebs der Turbinen entwickelt und in einem Turbinenteststand der Firma Siemens AG in Berlin erfolgreich getestet. Abschließend wurde eine Unsicherheitsanalyse durchgeführt, die eine erweiterte Messunsicherheit der gemessenen Temperaturen von etwa ± 30 K ergab. T2 - Development and test of a long wavelength infrared radiation thermometer for non-contact temperature measurements in gas turbines during operation KW - Berührungslose Temperaturmessung KW - Strahlungsthermometrie KW - Wärmedämmschicht KW - Gasturbine KW - Emissionsgrad KW - Infrarot-Strahlung KW - Non-contact temperature measurement KW - radiation thermometry KW - thermal barrier coating KW - gas turbine KW - emissivity KW - infrared radiation Y1 - 2017 U6 - https://doi.org/https://doi.org/10.1515/teme-2017-0077 VL - 85 IS - 1 SP - 28 EP - 39 PB - Oldenbourg Wissenschaftsverlag CY - Berlin/Boston ER - TY - CHAP A1 - Hartmann, Jürgen T1 - Eutektische Hochtemperatur-Fixpunkte für die Dynamische Differenzkalorimetrie N2 - Eutektische Metall-Kohlenstoff-(M-C)-Fixpunkte erweitern den Temperaturbereich in dem Hochtemperaturfixpunkte eingesetzt werden können vom höchsten Temperaturfixpunkt der derzeit gültigen Internationalen Temperaturskala von 1990 (ITS-90) der Erstarrungstemperatur von Kupfer bei 1357.77 K bis hin zu Temperaturen von bis zu 3500 K. Bislang sind diese Hochtemperaturfixpunkte ausschließlich eingesetzt worden, um die Kalibrierung von Strahlungsthermometern und Thermoelementen zu vereinfachen. Herkömmlicherweise ist das Fixpunktmaterial dabei in einem Graphittiegel, in den ein Hohlraumzylinder eintaucht, gefasst. Der Hohlraumzylinder dient dabei als Schwarzkörper für ein Strahlungsthermometer und als Tauchrohr für Anwendungen in der Berührungsthermometrie. Oberhalb von 1300 K würde auch die Messung thermophysikalischer Eigenschaften, d.h. Methoden der thermischen Analyse wie die dynamische Differenzkalorimetrie (DSC), die Laserflash-Methode oder die Dilatometrie, signifikant von der in-situ Anwendung der eutektischen Metallkohlenstoff-Fixpunkte profitieren. Der Beitrag präsentiert die Entwicklung und Untersuchung von Metallkohlenstoff-Hochtemperaturfixpunkten für die Anwendung in DSC Messapparaturen im Temperaturbereich bis 2300 K. Im Gegensatz zu der etablierten Anwendung in Strahlungsthemometrie und Berührungsthemometrie sind die Materialmengen, die für eine Temperaturkalibrierung benötigt werden, in der thermischen Analyse mit einigen Milligramm Fixpunktmaterial sehr gering. Spezielle Verfahren wurden dabei für die effektive Präparation solch kleiner, und für den Einsatz als Temperaturfixpunkt hochreiner, Probenmassen entwickelt. Y1 - 2010 PB - Sensoren und Messsysteme 2010 - 15. ITG/GMA-Fachtagung ER - TY - CHAP A1 - Hartmann, Jürgen T1 - Optische Hochtemperaturmesstechnik für die Thermometrie, Radiometrie und Photometrie N2 - Die Temperaturmessung über die emittierte Wärmestrahlung ist seit über hundert Jahren ein innovatives Feld der Messtechnik und der Grundlagenphysik. Ein erster Höhepunkt war Gustav Kirchhoffs theoretisches Prinzip eines Schwarzen Körpers mit idealen - von Material und Form unabhängigen - Emissionseigenschaften für Wärmestrahlung. Diese frühen Entwicklungen gipfelten in Max Planck’s berühmtem Strahlungsgesetz, das die Emission von Wärmestrahlung exakt beschreibt und den Beginn der modernen Quantenphysik einleitet. Die quantitative Messung von Wärmestrahlung erfordert die Kenntnis von Quellen- und Detektoreigenschaften. Im Bereich der Erzeugung von Wärmestrahlung werden noch heute die gleichen Prinzipien benutzt wie zu Zeiten Plancks, d. h. es werden technologisch weiter entwickelte Hohlraumstrahler zur Realisierung Schwarzer Körper eingesetzt. Im Bereich der Detektion von Wärmestrahlung haben sich jedoch durch die Entwicklung der Halbleitertechnik grundsätzlich andere physikalische Prinzipien durchgesetzt. Während zu Plancks Zeiten thermische Empfänger eingesetzt wurden, finden im Hochtemperaturbereich heute - neben thermischen Empfängern - fast ausschließlich photoelektrische Empfänger Anwendung. Einen weiteren entscheidenden Schritt in Richtung höchster Genauigkeit bedeutete die Entwicklung eines elektrischen Substitutionsradiometers bei sehr tiefen Temperaturen, des so genannten Kryoradiometers. Die Erfindung des Kryoradiometers als primärer Detektorstandard Ende der 1970er Jahre ermöglichte die Messung optischer Strahlungsleistung mit einer relativen Unsicherheit von unter 10-4. Basierend auf diese Strahlungsleistungsmessung ist heute die Kalibrierung der spektrale Empfindlichkeit von Detektoren mit relativen Unsicherheiten bis zu 10-4 möglich. Moderne Halbleiterempfänger liefern einen strahlungsleistungsproportionalen Photostrom. Zur Messung der Wärmestrahlung über einen weiten Temperatur- und Wellenlängenbereich müssen Photoströme von fA bis mA mit kleinster Unsicherheit bestimmt werden. Das stellt hohe experimentelle Anforderungen an die elektrische, geometrische und optische Messtechnik. Der Beitrag beschreibt kurz die historische Entwicklung der optischen Temperaturmessung über die ausgesandte Wärmestrahlung und geht dann auf die experimentellen und physikalischen Grundlagen dieser Methode ein. Abschließend werden Möglichkeiten zur Implementierung der im Metrologielabor erreichbaren niedrigen Messunsicherheiten in den praktischen messtechnischen Alltag vorgestellt. Y1 - 2010 PB - Sensoren und Messsysteme 2010 - 15. ITG/GMA-Fachtagung ER - TY - CHAP A1 - Hartmann, Jürgen T1 - Progress with the development of high temperature fixed-points in the EU through the Himert project N2 - The EU FP5 funded research project HIMERT (Novel High temperature Metal-carbon Eutectic fixed points for Radiation Thermometry, Radiometry and Thermocouples) aims to develop high temperature fixed points above the freezing point of copper to approximately 2500 deg C with a repeatability of less than 0.1 deg C. NPL and BNM-INM have constructed fixed-point blackbody sources, while BNM-LNE has constructed cells up to 1950 deg C (Ru-C) for the calibration of contact sensors. PTB will perform absolute radiometry of the cells constructed by NPL and BNM-INM. Pt-Pd thermocouple studies will be undertaken by PTB and BNM-LNE. Also a major materials compatibility study has been undertaken by BNM-LNE to identify thermocouple sheath materials that are compatible with graphite to 1950 deg C. The University of Valladolid is investigating the background physics of the eutectic process and seeking to develop physically realistic models. The two industrial companies will test whether improved traceability at lower uncertainties can be achieved by using metal-carbon eutectics. This paper describes the HIMERT project and current progress. (authors) Y1 - 2003 ER - TY - JOUR A1 - Hartmann, Jürgen T1 - A novel lens free high-accuracy InGaAs radiation thermometer for radiation temperatures above 300°C JF - VDI Berichte (1784) N2 - A novel high-accuracy radiation thermometer designed for laboratory applications and based on an InGaAs photon detector is presented. In contrast to other radiation thermometers, no imaging optics is used for collecting the radiation. By using a set of two equally sized optical apertures at fixed distances from the detector and a short distance of the thermometer from the radiation source, the size-of-source effect of the instrument is minimized. The radiation thermometer is designed for temperature measurements from 300°C upwards. Technical details of the radiation thermometer together with the measured reference function according to the ITS-90 up to 962°C and its temporal stability are presented. The size-of-source effect of the novel lens-free radiation thermometer is compared with the lens-based InGaAs reference radiation thermometer of the Physikalisch-Technische Bundesanstalt. Y1 - 2003 SP - 155 EP - 162 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Manara, Jochen A1 - Zipf, Matthias A1 - Stark, Thomas A1 - Arduini, Mariacarla A1 - Ebert, Hans-Peter A1 - Tutschke, Andreas A1 - Hallam, Andrew A1 - Hanspal, Jagdevinder A1 - Langley, Mark T1 - Development and validation of a long wavelength infrared (LWIR) radiation thermometer for contactless temperature measurements in gas turbines during operation T2 - EVI-GTI and PIWG Joint Conference on Gas Turbine Instrumentation N2 - A collection of slides from the author's conference presentation is given. The presentation introduces the infrared-optical characterization of thermal barrier coatings and the development of LWIR pyrometer for measuring temperature in an operating gas turbine. The test facility for evaluating the LWIR pyrometer is also presented. This presentation includes the experimental setup for LWIR calibration and measurement. Y1 - 2016 UR - https://ieeexplore.ieee.org/abstract/document/7827904 SP - 1 EP - 26 PB - IET ER - TY - CHAP A1 - Hartmann, Jürgen T1 - The PriTeRa facility of PTB for spectral radiance and irradiance calibrations and radiation thermometry in the range from À170 C up to 3200 C and from 200 nm up to 50 μm T2 - Proc. Newrad N2 - Blackbody radiators provide calculable spectral radiance and irradiance if their temperature and their emissivity is well known. Due to technical restrictions, one single blackbody can cover only a limited temperature range and therefore limited wavelengths for spectral radiance and irradiance calibrations. Space borne instruments for measuring the solar emission usually need calibrations from the UV to the near Infrared part of the optical spectrum [1] whereas remote sensing experiments for measuring earth surface temperatures for climate prediction or spaceborne instruments that deliver evidence for water on the surface of planet Mars [2] require calibration in the far infrared spectral range. To achieve these complementary requirements, PTB has set-up a series of blackbody based instrumentations, which are combined in the Primary Temperature Radiator facility (PriTeRa). To cover the whole wavelength range from 200 nm up to 800 µm different blackbody designs have to be applied. Y1 - 2008 UR - https://www.researchgate.net/profile/Juergen_Hartmann3/publication/313447537_The_PriTeRa_facility_of_PTB_for_spectral_radiance_and_irradiance_calibrations_and_radiation_thermometry_in_the_range_from_-170_C_up_to_3200_C_and_from_200_nm_up_to_50_mm/links/5f8580b2299bf1b53e230e35/The-PriTeRa-facility-of-PTB-for-spectral-radiance-and-irradiance-calibrations-and-radiation-thermometry-in-the-range-from-170-C-up-to-3200-C-and-from-200-nm-up-to-50-mm.pdf SP - 13 EP - 16 ER - TY - JOUR A1 - Hartmann, Jürgen T1 - The composition analysis of YBa2Cu3O7-δ or PrBa2Cu3O7-δ thin films and (YBa2Cu3O7-δ/PrBa2Cu3O7-δ) n heterostructures prepared by CVD JF - Fresenius' journal of analytical chemistry N2 - Some YBa2Cu3O7-δ films and heterostructures prepared by Chemical Vapor Deposition (CVD) were analyzed in our laboratories by EPMA-EDX or WDX, RBS, SNMS and AES. It was found that in some cases the results of composition analysis can significantly deviate from each other. At least two main reasons for these deviations exist: the different lateral resolution and the application of different reference samples for the calibration. Y1 - 1997 UR - https://link.springer.com/article/10.1007/s002160050305 VL - 357 IS - 8 SP - 1061 EP - 1065 ER - TY - RPRT A1 - Hartmann, Jürgen T1 - Improvement of the active layers of a field effect sensor for fluorine N2 - The quantitative determination of fluorine in gases is of great importance as this gas is often used in various industrial processes, but is toxic even at low concentrations. Therefore, there is a great demand for sensors for this gases and alarm systems controlling the environment. Recently, the auhtors reported on first results with a new field effect sensor for the determination of F {sub 2}. A silicon substrate was used with a thin layer of LaF {sub 3} in direct contact to the semiconductor and platinum electrode on the top. In early results, a good sensitivity was achieved but an insufficient stability and limit of detection required further improvements. The corresponding findings and fundamental investigations on the sensor mechanism will be given in this paper. Y1 - 1996 ER - TY - JOUR A1 - Hartmann, Jürgen T1 - Thermal resistance of thermal barriers in polycrystalline diamond JF - Progress in Natural Science N2 - Micrometer resolved photoțhermal measurements on chemical vapour deposited (CVD) diamond are presented. It is shown that the thermal conductivity inside the grains is as high as that of natural IIa diamond. Using two different approaches we measure the thermal resistance of thermal barriers like grain boundaries or microcracks and obtain values of the order of 10" m'Kw. A simple model is presented, relating the overall thermal conductivity for one-dimensional heat flow to the thermal resistance at barriers and the average size of the grains. Good agreernent between predictions and literature data is found, ... Y1 - 1996 IS - 6 SP - 297 ER - TY - JOUR A1 - Hartmann, Jürgen T1 - Development and test of a long wavelength infrared radiation thermometer for non-contact temperature measurements in gas turbines during operation JF - Technisches Messen N2 - The aim of this work was the development of a long wavelength infrared radiation thermometer for the non-contact measurement of surface temperatures in stationary gas turbines during operation within the EU-project, Sensors Towards Advanced Monitoring and Control of Gas Turbine Engines (acronym STARGATE)". In this work, the infrared-optical properties of the thermal barrier coatings and the combustion gases were determined at ZAE Bayern at high temperatures up to 1600 K and pressures up to 13 bar. Based on these experimental characterizations, a suitable spectral range could be identified which lies around 10 mu m for the long-wavelength infrared radiation thermometer. According to these findings, a laboratory setup with suitable optical components (filters, IR-fibers, etc.) was firstly realized and verified. Subsequently, a prototype for measurements in gas turbines during operation of the turbines has … Y1 - 2018 VL - 85 IS - 1 SP - 28 EP - 39 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Harrer, S. A1 - Dotterweich, C. A1 - Zink, Markus H. A1 - Hemberger, Frank A1 - Ebert, Hans-Peter A1 - Schnitzler, Tim T1 - Phase change materials for use in thermally and electrically stressed insulation for high voltage applications T2 - 2016 IEEE Electrical Insulation Conference N2 - The temperature of high voltage equipment is often the limiting factor when transmitting electrical energy because the electrical insulation can get severely aged when the temperature is exceeding a certain limit. Hence, cooling has to be improved or heat generation must be reduced to avoid damage of the insulation. In this paper a new method was examined by investigating electrically insulating phase change materials which are able to store latent heat during a phase change from the solid to liquid state in times of high energy demand. To verify the electrically insulating properties of paraffins, one class of phase change materials, a special test cell was designed allowing the determination of breakdown voltage of phase change materials. The measurements on one paraffin sample proved the promising electrical insulating properties and it was shown that the breakdown voltage in the liquid state is comparable … Y1 - 2016 UR - https://ieeexplore.ieee.org/iel7/7541933/7548553/07548675.pdf SN - 978-1-4673-8706-4 SP - 605 EP - 608 PB - IEEE ER - TY - CHAP A1 - Hartmann, Jürgen T1 - I3. 4-Radiometric calibration of the NIRSpec instrument on the James Webb Space Telescope in the wavelength range from 0.7 μm to 5.0 μm T2 - SENSOR+TEST Conference 2009 - IRS² 2009 Proceedings Y1 - 2009 UR - http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.1019.284&rep=rep1&type=pdf SP - 249 EP - 254 ER - TY - JOUR A1 - Hartmann, Jürgen T1 - Strahlungsthermometrie BT - Temperaturen berührungslos messen JF - PTB-Mitteilungen 117 N2 - Der prinzipielle Aufbau eines Strahlungsthermometers ist in Bild 2 dargestellt. Eine Optik bildet das Messobjekt mittels der Wärmestrahlung auf die Gesichtsfeldblende vor dem Detektor ab. Die Aperturblende und die Gesichtsfeldblende definieren den Raumwinkel und die Fläche (Messfeld) der vom Detektor nachgewiesenen Strahlung. Bei den meisten Strahlungsthermometern wird ein Spektralfilter zur Eingrenzung des Wellenlängenbereiches der auf den Detektor treffenden Strahlung verwendet. Dieser Spektralfilter wird oft unmittelbar vor dem Detektor angeordnet oder ist als Fenster in das Detektorgehäuse integriert. Bei hochwertigen Strahlungsthermometern wird der Detektor und manchmal auch zusätzlich der Spektralfilter temperiert. Interne Referenzstrahlungsquellen oder nur die Messung und Verarbeitung der internen Temperatur des Detektors oder der optischen Komponenten sorgen im allgemeinen für eine stabile Anzeige von Messwerten der Strahlungstemperatur innerhalb eines weiten Eigentemperaturbereichs des Strahlungsthermometers. Die Leistungsfähigkeit eines Strahlungsthermometers wird wesentlich von der Güte seiner Optik und der Empfindlichkeit seines Strahlungsempfängers bestimmt. Hochwertige Strahlungsthermometer arbeiten mit einem festen Fokus, der dem empfohlenen Messabstand entspricht, oder mit variablem Fokus zur Anpassung an den Messabstand. Aus der abstandsabhängigen Einstellung des Fokus resultiert ein Messfeld, in dem die mittlere Strahlungstemperatur des Messobjektes ermittelt wird. Genaue Messungen der Strahlungstemperatur sollten mit abbildenden optischen Systemen erfolgen … Y1 - 2007 UR - http://www.relativity.li/uploads/pdf/weitere/PTB_2007_Heft_3.pdf#page=53 VL - 117 IS - 3 SP - 272 EP - 281 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Taubert, Dieter Richard A1 - Monte, C. A1 - Gutschwager, B. A1 - Hollandt, Jörg T1 - Traceable calibration of radiation sources from the visible to the far infrared for space borne applications at PTB T2 - Proceedings of SPIE Volume 7474, Sensors, Systems, and Next-Generation Satellites XIII N2 - The Physikalisch-Technische Bundesanstalt (PTB) has developed dedicated instrumentations and methods for the traceable calibration of space borne instruments in terms of the three fundamental radiometric units, i.e. spectral radiance (radiation temperature), spectral radiant intensity and spectral photon flux. The traceable calibration under conditions similar to the space environment is achieved by use of two major radiometric calibration facilities of PTB, the Spectral Radiance Comparator Facility (SRCF) and the Reduced Background Calibration Facility (RBCF) which are part of the Primary Temperature Radiator Facility of PTB and cover the wavelength range from the UV to the FIR (THz range). The improved detector instrumentations of the SRCF and RBCF, detailed calibration schemes and results of calibrations for space missions are presented. Y1 - 2009 UR - https://doi.org/10.1117/12.830082 ER - TY - CHAP A1 - Hartmann, Jürgen ED - Zvizdic, D. T1 - Long term stability of the spectral responsivity of filter radiometers at the PTB T2 - Proc. of TEMPMEKO N2 - The Physikalisch-Technische Bundesanstalt (PTB) uses calibrated filter radiometers to measure the thermodynamic temperature of blackbodies applied for the realisation and dissemination of the spectral radiance and spectral irradiance. This paper presents the PTB experience with the stability of the spectral responsivities of two different sets of filter radiometers, a set of four broad-band filter radiometers with centroid wavelengths in the visible spectral range (437 nm, 510 nm, 558 nm and 728 nm), using a combination of coloured glass filters as wavelength selective elements and a set of five narrow-band interference filter radiometers with centroid wavelengths in the visible and in the near infrared wavelength range (676 nm, 802 nm, 903 nm and 1003 nm). The time period of their continuous investigation with respect to the relevant stability parameters, the integrated spectral responsivity and the centroid wavelength, is about seven years for the broad-band filter radiometers and up to ten years for the narrow-band interference filter radiometers. Both types of filter radiometers show sufficient stability for their application as high-accuracy temperature measurement instruments. Relative changes in the integrated spectral responsivity up to some parts in 103 and for the interference filter radiometers a linear increase of the centroid wavelength with time in the order of several ten picometers per year have been observed. A comparison between the two types of filter radiometers is given, with respect to the contribution of the stability of these parameters to the uncertainty budget of thermodynamic temperature determination. Reasons for the observed … Y1 - 2004 UR - https://www.researchgate.net/profile/Juergen_Hartmann3/publication/259810265_Long_Term_Stability_of_the_Spectral_Responsivity_of_Filter_Radiometers_at_the_PTB/links/5f4cc8dba6fdcc14c5f4740e/Long-Term-Stability-of-the-Spectral-Responsivity-of-Filter-Radiometers-at-the-PTB.pdf SP - 977 EP - 982 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - McEvoy, H.C. A1 - Machin, Graham A1 - Friedrich, R. A1 - Hollandt, Jörg T1 - Comparison of the New NPL Primary Standard Ag Fixed‐Point Blackbody Source with the Primary Standard Fixed Point of PTB T2 - AIP Conference Proceedings (684) N2 - Above the freezing point of silver (961.78 °C), the International Temperature Scale of 1990 is defined in terms of Planck’s radiation law. The scale is maintained and disseminated using a validated and linear pyrometer in conjunction with a blackbody reference source at either the Ag, Au (1064.18 °C) or Cu (1084.62 °C) freezing point. In order to realize the scale with the highest precision high quality, well‐characterised, reproducible fixed‐point blackbody sources are required. Such sources have been maintained at NPL for a number of years, but it was felt that improvements to the design would be beneficial. A new Ag point blackbody source has therefore been constructed. The new design will improve the quality and reproducibility of the melting and freezing plateaux and reduce errors due to the ‘out‐of‐focus’ size‐of‐source effect which is difficult to measure and to eliminate. Full details of the design of the new … Y1 - 2003 UR - https://aip.scitation.org/doi/abs/10.1063/1.1627244 SN - 0-7354-0153-5 SP - 909 EP - 914 PB - American Institute of Physics ER -