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 - 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 - 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 - JOUR A1 - Hartmann, Jürgen A1 - Zipf, Matthias A1 - Manara, Jochen A1 - Stark, Thomas A1 - Arduini, Mariacarla A1 - Ebert, Hans-Peter T1 - Infrared-optical characterization of emitting and absorbing gases at high temperatures and high pressures JF - High Temperatures – High Pressures N2 - In the context of the optimization of stationary gas turbines, the surface temperatures of the turbine blades have to be measured by a non-contact technique using radiation thermometers during operation of the turbine. Nowadays turbine blades are protected by thermal barrier coatings. The infrared-optical properties of these coatings require the usage of the MIR or LWIR region for non-contact measurement of the surface temperatures. For performing such measurements and for properly analyzing the derived data, the transmission and absorption spectra of the combustion gas mixture within the turbine were determined at the local conditions during operation of the turbine. Therefore, subject of this work is the measurement of the transmission spectra of carbon dioxide and water vapor at high temperatures and high pressures to identify a wavelength range, which is almost free of absorption and emission effects. In … Y1 - 2018 VL - 47 IS - 1 SP - 3 EP - 21 ER - TY - JOUR A1 - Jürgen, Hartmann A1 - Arduini, Mariacarla A1 - Manara, Jochen A1 - Stark, Thomas A1 - Ebert, Hans-Peter T1 - Development and Evaluation of an Improved Apparatus for Measuring the Emissivity at High Temperatures JF - Sensors N2 - An improved apparatus for measuring the spectral directional emissivity in the wavelength range between 1 µm and 20 µm at temperatures up to 2400 K is presented in this paper. As a heating unit an inductor is used to warm up the specimen, as well as the blackbody reference to the specified temperatures. The heating unit is placed in a double-walled vacuum vessel. A defined temperature, as well as a homogenous temperature distribution of the whole surrounding is ensured by a heat transfer fluid flowing through the gap of the double-walled vessel. Additionally, the surrounding is coated with a high-emitting paint and serves as blackbody-like surrounding to ensure defined boundary conditions. For measuring the spectral directional emissivity at different emission angles, a movable mirror is installed in front of the specimen, which can be adjusted by a rotatable arrangement guiding the emitted radiation into the attached FTIR-spectrometer. The setup of the emissivity measurement apparatus (EMMA) and the measurement procedure are introduced, and the derived measurement results are presented. For evaluating the apparatus, measurements were performed on different materials. The determined emissivities agree well with values published in literature within the derived relative uncertainties below 4% for most wavelengths. KW - emissivity KW - reflectivity KW - infrared radiation KW - high temperature KW - Temperatur KW - Emissivität Y1 - 2021 UR - https://www.mdpi.com/1424-8220/21/18/6252 U6 - https://doi.org/10.3390/s21186252 SN - 1424-8220 VL - 21 IS - 18 ER - TY - JOUR A1 - Manara, Jochen A1 - Hartmann, Jürgen A1 - Kerwagen, Fabian A1 - Maak, Christoph A1 - Muscio, Albert A1 - Paeth, Heiko A1 - Ebert, Hans-Peter T1 - Passive Radiative Cooling Materials with Special Focus on the Reduction of Urban Heat Island Effect: A Current Summarized Classification of Need, Approaches and Characterization Methods JF - International Journal of Thermophysics N2 - Rapidly rising global temperatures and the intensification of the urban heat island (UHI) effect necessitate new, energy-efficient solutions to mitigate heat stress in cities. Passive radiative cooling (PRC) offers a highly promising, low-energy pathway to achieve sub-ambient temperatures by reflecting incoming solar radiation while emitting long-wave infrared radiation through the atmospheric infrared window. This review summarizes key aspects of PRC and its role in reducing UHI impacts. Furthermore the fundamental physics of heat transfer and radiative heat exchange, including the materials properties such as solar reflectance and thermal emissivity which are correlated with the figures of merit, temperature drop below ambient temperature and cooling power. A comprehensive classification of current PRC materials is presented based on both structural architectures and physical effects. Additionally an overview on measurement techniques are employed to determine the performance of PRC materials, focusing on the key performance indicators. For this purpose in-field as wells as laboratory measurement techniques are introduced and opportunities in standardizing testing protocols are highlighted. Finally, future research directions are outlined, focusing on novel material development, theoretical advancements, scalable fabrication processes, and integration strategies within urban infrastructures. These innovations are important for enhancing building energy efficiency, reducing urban heat stress, and promoting sustainable urban development in the face of climate change. Y1 - 2025 U6 - https://doi.org/10.1007/s10765-025-03529-1 VL - 46 IS - 58 ER -