TY - JOUR A1 - Chaudhuri, Somsubhro A1 - Stamm, Michael A1 - Lapšanská, Ivana A1 - Lançon, Thibault A1 - Osterbrink, Lars A1 - Driebe, Thomas A1 - Hein, Daniel A1 - Harendt, René T1 - Infrared Thermography of Turbulence Patterns of Operational Wind Turbine Rotor Blades Supported With High‐Resolution Photography: KI‐VISIR Dataset N2 - With increasing wind energy capacity and installation of wind turbines, new inspection techniques are being explored to examine wind turbine rotor blades, especially during operation. A common result of surface damage phenomena (such as leading edge erosion) is the premature transition of laminar to turbulent flow on the surface of rotor blades. In the KI-VISIR (Künstliche Intelligenz Visuell und Infrarot Thermografie—Artificial Intelligence-Visual and Infrared Thermography) project, infrared thermography is used as an inspection tool to capture so-called thermal turbulence patterns (TTPs) that result from such surface contamination or damage. To complement the thermographic inspections, high-resolution photography is performed to visualise, in detail, the sites where these turbulence patterns initiate. A convolutional neural network (CNN) was developed and used to detect and localise turbulence patterns. A unique dataset combining the thermograms and visual images of operational wind turbine rotor blades has been provided, along with the simplified annotations for the turbulence patterns. Additional tools are available to allow users to use the data requiring only basic Python programming skills. KW - Thermography KW - Thermografie KW - Wind energy KW - Leading edge erosion KW - KI PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615772 DO - https://doi.org/10.1002/we.2958 IS - e2958 SP - 1 EP - 9 PB - Wiley AN - OPUS4-61577 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Krankenhagen, Rainer A1 - Chaudhuri, Somsubhro A1 - Stamm, Michael A1 - Lapšanská, Ivana A1 - Aderhold, J. A1 - Schlüter, F. T1 - EvalTherm – Evaluierung der passiven Thermografie für die Zustandsbewertung von Rotorblättern an Windenergieanlagen N2 - Der Bericht gibt einen Überblick über im Rahmen des Projektes durchgeführte Forschungsarbeiten sowie ausgewählte Ergebnisse. Er wurde zusammen mit dem FhI für Holzforschung (WKI) erstellt. KW - Rotorblattinspektion KW - Passive Thermografie KW - Feldmessungen KW - Windturbine PY - 2025 N1 - Schlussbericht des Projektes N1 - Laufzeit: 1.9.2020 – 31.8.2024 N1 - Das Verbundprojekt wurde im Rahmen des 7. Energieforschungsprogramms "Innovationen für die Energiewende" gefördert N1 - Das Vorhaben wurde mit Mitteln des Bundesministeriums für Wirtschaft und Klima unter dem Förderkennzeichen 03EE3035A/B gefördert SP - 1 EP - 67 PB - Technische Informationsbibliothek (TIB) CY - Hannover AN - OPUS4-62647 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stamm, Michael A1 - Sridaran Venkat, Ramanan T1 - Harnessing the power of thermal imagery and visual inspection- a mean for reliable damage detection of wind turbine rotor blades N2 - Generation of green electricity as part of the energy transition is leading to a growing market in the wind energy sector all over the world. Maintenance and inspection are key to the reliability, safety and efficiency of wind turbines, the regular maintenance of rotor blades focuses on damage such as erosion on the leading edge of the profile, delamination and thermal cracks due to lightning strikes. To date, visual inspection by technicians (climbers) has been the state of the art and it is time consuming besides posing safety risk for themselves. Recently, drone-based inspections using visual cameras have become more common, enabling fast, reliable and cost-effective inspections. However, no internal damage to the rotor blades can be detected during such an inspection. Thermography is a recognised method for detecting damage beneath the surface of an object, which has been promoted and further developed at BAM for years. To enhance the accuracy and reliability of wind turbine blade inspection, the fusion o T2 - 11th European Workshop on Structural Health Monitoring CY - Potsdam, Germany DA - 10.06.2024 KW - Wind rotor blade inspection KW - Thermography KW - Data fusion KW - Drone inspection KW - Multi-sensors PY - 2024 AN - OPUS4-62515 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stamm, Michael T1 - AI-Assisted thermographic and visual classification of leading-edge erosion of wind turbine blades N2 - The wind industry is crucial for carbon neutrality, with turbines featuring blades over 100 meters long. Regular inspections, often manual and visual, struggle to capture subsurface damage or airflow dynamics. Leading-edge erosion, caused by rain and hail, significantly reduces turbine efficiency. The Federal Institute for Materials Research and Testing (BAM) in Berlin is working with industry partners to classify leading-edge damage and estimate yield loss using ground-based thermographic images. These images visualize airflow disruptions caused by erosion. AI models, trained on 1500 thermographic images, can detect and classify this damage. BAM aims to create a reference dataset by 2024, using data from 30 wind turbines. This dataset will include simultaneous thermographic and high-resolution visual images. The project also explores predicting stall and calculating performance loss due to erosion. A secure data platform facilitates data exchange and federated learning, enhancing AI systems with diverse data. KW - NDT KW - Thermography KW - Wind Turbine Blades KW - AI KW - KI-VISIR PY - 2024 UR - https://source.asnt.org/226h005/ SN - 0025-5327 VL - 82 IS - 6 SP - 14 EP - 15 AN - OPUS4-62452 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Junker, Birgit A1 - Stamm, Michael T1 - No downtime thermographic rotor blade inspection N2 - In this presentation, the KI-VISIR Reference Dataset, created by the Bundesanstalt für Materialforschung und -prüfung (BAM) will be discussed. It includes thermographic and visual inspection data of 30 operational wind turbines. This dataset aims to support the maintenance and inspection of wind turbines, which are increasingly being built across Germany and Europe. The data is publicly available and helps in the development of digital methods for damage classification and inspection. T2 - AMI Wind Turbine Blades CY - Düsseldorf, Germany DA - 10.12.2024 KW - Thermography KW - Wind Turbine Blades KW - AI KW - KI-VISIR KW - NDT PY - 2024 AN - OPUS4-62498 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stamm, Michael T1 - Damage detection of wind turbine blades with thermographic inspection and AI-based classification N2 - In this presentation, the possibilities, limitations and challenges of thermographic rotor blade inspection will be discussed. Among other things, the data from the KI-VISIR reference data set will be discussed. This data was also used to train an AI-based image recognition system. T2 - WindEurope Technology Workshop 2024 CY - Dublin, Ireland DA - 10.06.2024 KW - Thermography KW - Wind Turbine Blades KW - AI KW - KI-VISIR KW - NDT PY - 2024 AN - OPUS4-62499 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ratkovac, Mirjana A1 - Gerards-Wünsche, Paul A1 - Thiele, Marc A1 - Brackrock, Daniel A1 - Stamm, Michael T1 - Detection and monitoring of the fatigue crack growth on welds – Application-oriented use of NDT methods N2 - Early detection of fatigue cracks and accurate measurements of the crack growth play an important role in the maintenance and repair strategies of steel structures exposed to cyclic loads during their service life. Observation of welded connections is especially of high relevance due to their higher susceptibility to fatigue damage. The aim of this contribution was to monitor fatigue crack growth in thick welded specimens during fatigue tests as holistically as possible, by implementing multiple NDT methods simultaneously in order to record the crack initiation and propagation until the final fracture. In addition to well-known methods such as strain gauges, thermography, and ultrasound, the crack luminescence method developed at the Bundesanstalt für Materialforschung und -prüfung (BAM), which makes cracks on the surface particularly visible, was also used. For data acquisition, a first data fusion concept was developed and applied in order to synchronize the data of the different methods and to evaluate them to a large extent automatically. The resulting database can ultimately also be used to access, view, and analyze the experimental data for various NDT methods. During the conducted fatigue tests, the simultaneous measurements of the same cracking process enabled a comprehensive comparison of the methods, highlighting their individual strengths and limitations. More importantly, they showed how a synergetic combination of different NDT methods can be beneficial for implementation in large-scale fatigue testing but also in monitoring and inspection programs of in-service structures - such as the support structures of offshore wind turbines. T2 - Fatigue Design 2023 (FatDes 2023) CY - Senlis, France DA - 29.11.2023 KW - Fatigue KW - Welded KW - NDT KW - Crack growth PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600238 DO - https://doi.org/10.1016/j.prostr.2024.03.062 VL - 57 SP - 560 EP - 568 PB - Elsevier B.V. AN - OPUS4-60023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lay, Vera A1 - Baensch, Franziska A1 - Skłodowska, Anna A1 - Fritsch, Tobias A1 - Stamm, Michael A1 - Prabhakara, Prathik A1 - Johann, Sergej A1 - Sturm, Patrick A1 - Kühne, Hans-Carsten A1 - Niederleithinger, Ernst T1 - Multi–sensory Monitoring and Non–destructive Testing of New Materials for Concrete Engineered Barrier Systems N2 - The crucial part of nuclear waste storage is the construction of sealing structures made of reliable, safe and well–understood materials. We present an extended analysis of long-term multi–sensory monitoring and non–destructive testing (NDT) inspection of two laboratory specimens aiming at potential materials for sealing structures for nuclear waste repositories. Specimens with a volume of 340 litres made from newly developed alkali–activated materials (AAM) and established salt concrete (SC) were analysed using embedded acoustic emission and wireless radio-frequency identification (RFID) sensors, ultrasonic echo imaging, active thermography, and X–ray computed tomography. The monitoring analysis showed lower heat of reaction and 50% less acoustic emission events in AAM compared to SC. However, due to the surface effects of the AAM material, the number of acoustic emission events increased significantly after approximately two months of monitoring. Subsequently performed NDT inspections reliably located embedded sensors and confirmed the absence of major cracks or impurities. The presented laboratory results show the feasibility and potential of comprehensive NDT monitoring and inspection to characterise cementitious and alternative materials as well as the need for multi–parameter long–term monitoring. Thus, our study demonstrates that tailored NDT investigations will help to develop safe sealing structures for nuclear waste repositories. KW - Radioactive waste KW - Barrier KW - Concrete KW - AAM KW - Non-destructive testing PY - 2024 DO - https://doi.org/10.3151/jact.22.516 SN - 1347-3913 VL - 22 IS - 9 SP - 516 EP - 529 PB - Japan Concrete Institute AN - OPUS4-61461 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lay, Vera A1 - Mielentz, Frank A1 - Prabhakara, Prathik A1 - Baensch, Franziska A1 - Johann, Sergej A1 - Hofmann, Detlef A1 - Sturm, Patrick A1 - Stamm, Michael A1 - Niederleithinger, Ernst T1 - Multi-sensory monitoring and ultrasound for quality assurance at underground sealing structures N2 - Within the safety concepts of underground disposal sites of nuclear waste, engineered barriers play an important role. As these sealing structures have high demands concerning integrity, we aim at advancing the available construction materials, monitoring, and inspection techniques within the project SealWasteSafe. A specifically developed alkali-activated material is compared to classical salt concrete. A comprehensive multi-sensory monitoring scheme is used at 150-340 l specimens to monitor setting and hardening of both materials. All sensors are demonstrated to resist the highly alkaline environments. Besides cabled and wireless temperature and humidity of the materials, strain variations using fibre optic sensors and acoustic emissions are recorded over periods of at least 28 days, partly for more than eight months. After hardening of the specimens, further nondestructive evaluations using ultrasonic echo and thermographic measurements are conducted. Preliminary results proof the suitability of the tested sensors and clearly highlight differences between the tested materials. Particularly, the newly developed alkali-activated material shows lower acoustic emission activity indicating less cracking activity. Additionally, unique ultrasonic methods will enable better images of potential internal objects and cracks at in-situ sealing structures. A largescale ultrasonic system is optimised to reliably detect objects at a depth exceeding 9 m while still obtaining a good resolution. Modelling studies show the potential of further increasing the distance between individual transducer arrays. Additionally, a new ultrasonic borehole probe using phased arrays allowing for beam focussing is constructed and tested. Laboratory measurements at a halfcylindrical concrete specimen coincide well with the previous modelling. In total, the presented safe materials, detailed monitoring approaches and ultrasonic quality assurance methods will help to obtain safe sealing structures within salt as a host rock. The concepts can partly be transferred to sealing structures in alternative host rocks and will also be valuable for non-nuclear waste repositories. T2 - NDE NucCon CY - Espoo, Finland DA - 25.01.2023 KW - SealWasteSafe KW - Engineered barriers KW - Monitoring KW - Embedded sensors KW - Ultrasonic imaging PY - 2023 SP - 2 EP - 10 AN - OPUS4-56928 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chaudhuri, Somsubhro A1 - Krankenhagen, Rainer A1 - Lapšanská, Ivana A1 - Stamm, Michael T1 - WTB-IRT: Modelling and Measurement of Thermal Contrast in Wind Turbine Rotor Blades (WTBs) N2 - The rapid growth of wind energy infrastructure over the past two to three decades has led to an urgent need for advanced non-destructive testing (NDT) methods—both for newly installed wind turbine blades (WTBs) and for ageing components nearing the end of their service life. Among emerging techniques, passive infrared thermography (IRT) offers a promising solution by enabling contactless, time-efficient inspection based on naturally occurring thermal variations. The effectiveness of passive IRT depends on the presence of sufficient thermal contrast to distinguish surface features, subsurface structures, and defects. To better understand the possibility of obtaining such contrast in composite structures such as WTBs, a controlled study was carried out on a blade section exposed to programmed temperature transients in a climate chamber. Infrared measurements were recorded, and the thermal behaviour of the specimen was simulated using finite element models (FEM) in COMSOL Multiphysics 6.3. Although direct validation is limited by measurement uncertainties and transient effects, the comparison provides insight into the capabilities and limitations of FEM in replicating real-world thermal behaviour. This paper focuses specifically on the challenges related to the modelling approach. T2 - 18th International Workshop on Advanced Infrared Technology and Applications (AITA 2025) CY - Kobe, Japan DA - 15.09.2025 KW - Thermography KW - Wind energy KW - Wind turbine rotor blades KW - Windenergie Anlage Rotorblätter KW - FEA PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-642308 DO - https://doi.org/10.3390/proceedings2025129015 VL - 129 IS - 1 SP - 1 EP - 5 PB - MDPI CY - Basel AN - OPUS4-64230 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stamm, Michael T1 - The KI-VISIR Reference Dataset: A Compilation of Thermal and Visual Inspection Data for Quantifying Leading Edge Rain Erosion N2 - This presentation introduces thermography (thermal imaging) as a key method for non-destructive testing (NDT) of wind turbine rotor blades. By leveraging solar heating and aerodynamic effects, passive thermography detects internal defects, delaminations, and surface issues like leading edge erosion. We discuss field measurements, the role of AI/Machine Learning (LATODA) for automated defect classification, and its importance for improving O&M efficiency and lifetime extension in the wind energy sector. T2 - WindEurope Annual Event 2025 CY - Copenhagen, Denmark DA - 08.04.2025 KW - Thermography KW - Wind Turbine Blades KW - AI KW - NDT KW - KI-VISIR PY - 2025 AN - OPUS4-64721 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stamm, Michael T1 - Einführung thermografischer Methoden in die Ermüdungsprüfung unter Laborbedingungen sowie bei Ganzblatt-Rotorblattprüfungen N2 - Der Vortrag der Bundesanstalt für Materialforschung und -prüfung (BAM) stellt die Einführung und Anwendung thermografischer Methoden zur Ermüdungsprüfung und Ganzblatt-Rotorblattprüfung vor. Die BAM, tätig in Forschung, Prüfung und Beratung, trägt zur technischen Sicherheit bei und unterstützt die Energiewende. Die Abteilung 8.3 "Thermographic Methods" arbeitet an der Forschung, Entwicklung und Anwendung thermografischer Prüf- und Überwachungstechniken. Passive Thermografie ist eine bildgebende Messung der Oberflächentemperatur, die Informationen über das Innere von Bauteilen liefert. Durch Nutzung von Sonneneinstrahlung und Temperaturschwankungen können auch große Strukturen wie Rotorblätter geprüft werden. Thermische Inspektionen visualisieren Temperaturunterschiede, die durch Material-, Struktur-, Aerodynamik- und Oberflächeneigenschaften sowie Reibungswärme entstehen. Bei rotierenden Rotorblättern wird die Thermografie eingesetzt, um Strömungsphänomene (laminar/turbulent), Oberflächendefekte (z.B. Regen-Erosion) und innere Defekte zu erkennen. Ein Schlüsselprojekt ist die AI-gestützte Bildklassifizierung (LATODA) von über 1200 Roh-Infrarotbildern für die Mangeldetektion. Ziel ist die Entwicklung von zuverlässigen, automatisierten, robotergestützten Verfahren, um Schäden schnell zu erkennen und so Effizienzverluste (AEP-loss) zu vermeiden und die Lebensdauer von Windenergieanlagen zu verlängern. T2 - Mitgliederversammlung des BWE- Sachverständigenbeirates CY - Hannover, Germany DA - 5.9.2025 KW - Thermografie KW - Wind KW - Rotorblätter KW - Inspektion PY - 2025 AN - OPUS4-64719 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -