TY - JOUR A1 - Hüllmann, Dino A1 - Paul, Niels A1 - Kohlhoff, Harald A1 - Neumann, Patrick P. A1 - Lilienthal, A. J. ED - Eberhardsteiner, J. ED - Růžička, M. ED - Cosmi, F. T1 - Measuring rotor speed for wind vector estimation on multirotor aircraft N2 - For several applications involving multirotor aircraft, it is crucial to know both the direction and speed of the ambient wind. In this paper, an approach to wind vector estimation based on an equilibrium of the principal forces acting on the aircraft is shown. As the thrust force generated by the rotors depends on their rotational speed, a sensor to measure this quantity is required. Two concepts for such a sensor are presented: One is based on tapping the signal carrying the speed setpoint for the motor controllers, the other one uses phototransistors placed underneath the rotor blades. While some complications were encountered with the first approach, the second yields accurate measurement data. This is shown by an experiment comparing the proposed speed sensor to a commercial non-contact tachometer. T2 - 34th Danubia Adria Symposium on Advances in Experimental Mechanics CY - Trieste, Italy DA - 19.09.2017 KW - Wind vector estimation KW - Rotor speed KW - UAV KW - Tachometer PY - 2018 UR - https://www.sciencedirect.com/science/article/pii/S2214785318321114 DO - https://doi.org/10.1016/j.matpr.2018.08.139 SN - 2214-7853 VL - 5 IS - 13 SP - 26703 EP - 26708 PB - Elsevier CY - Amsterdam, Netherlands AN - OPUS4-47097 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hüllmann, Dino A1 - Kohlhoff, Harald A1 - Erdmann, Jessica A1 - Neumann, Patrick P. ED - Emri, Igor T1 - Current-independent torque control of permanent-magnet synchronous motors N2 - A current-independent torque equation for the permanent-magnet synchronous motor (PMSM) aiming at direct-drive servo applications is derived from a first principles model. Instead of measuring currents, all required control parameters are derived from optical incremental encoder measurements. The results are verified on a real system in test series showing the effect of static friction and proving the obtained torque model. T2 - 33rd Danubia Adria Symposium on Advances in Experimental Mechanics CY - Portorož, Slovenia DA - 20.09.2016 KW - BLDC KW - Motor control KW - PMSM KW - Servo drive PY - 2017 UR - http://www.sciencedirect.com/science/article/pii/S2214785317308271 DO - https://doi.org/10.1016/j.matpr.2017.06.052 SN - 2214-7853 VL - 4 IS - 5 SP - 5821 EP - 5826 PB - Elsevier CY - Amsterdam, Netherlands AN - OPUS4-41580 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ullner, Christian A1 - Reimann, E. A1 - Kohlhoff, Harald A1 - Subaric-Leitis, Andreas T1 - Effect and measurement of the machine compliance in the macro range of instrumented indentation test N2 - The contribution concerns the strong effect of the machine compliance in the upper macro range of the instrumented indentation test on hard materials. To achieve a minimum uncertainty in determination of the machine compliance the measurement and analysis needed for the determination are studied in detail. Based on the assumption that the hardness and/or the indentation modulus are force independent, four methods on the determination of the machine compliance are described. Experimental results of a commercial testing machine up to 2500 N and of a standard machine up to 200 N are analyzed. The results show that the uncertainty of the compliance is usually higher than requested for a precisely enough determination of hardness and further materials parameters. Especially for the calibration of reference materials with high hardness and/or Young’s modulus, the machine compliance should be limited in ISO 14577 part 3, 2003 [1]. KW - Instrumented indentation test KW - Compliance KW - Uncertainty PY - 2010 DO - https://doi.org/10.1016/j.measurement.2009.09.009 SN - 0263-2241 SN - 1873-412X VL - 43 IS - 2 SP - 216 EP - 222 PB - The Institute of Measurement and Control CY - London AN - OPUS4-20671 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kohlhoff, Harald A1 - Knapp, Jürgen T1 - Pneumatischer Schrittmotor für EMV-Tests KW - EMV-Prüfung PY - 2000 SN - 0177-7297 VL - 36 IS - 9 SP - 52 EP - 54 PB - b-Quadrat-Verl.-GmbH CY - Kaufering AN - OPUS4-905 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mansurova, Maria A1 - Johann, Sergej A1 - Kohlhoff, Harald A1 - Rurack, Knut A1 - Bartholmai, Matthias A1 - Bell, Jérémy T1 - On-Site Analytical Tool Based on Crude Oil Fluorescence and Chemometrics for the Rapid Determination of the Nature and Essential Properties of Oil Spills N2 - With the reduction of large oil spills because of stricter regulations and safety measures, the question of how to manage smaller oil spills arises. Few on-site analytical tools are available for first responders or other law enforcement personnel to rapidly test for crude oil in the early management of localized polluted areas. The approach reported here relies on well-described computer-assisted multivariate data analysis of the intrinsic fluorescence fingerprints of crude oils to build a multivariate model for the rapid classification of crude oils and the prediction of their properties. Thanks to a dedicated robust portable reader, the method allowed classification and accurate prediction of various properties of crude oil samples like density (according to API, the American Petroleum Institute and viscosity as well as composition parameters such as volume fractions of paraffins or aromatics. In this way, autonomous operation in on-site or in-the-field applications becomes possible based on the direct (undiluted and untreated) measurement of samples and a rapid, tablet-operated readout system to yield a robust and simple analytical test with superior performance. Testing in real-life scenarios allowed the successful classification and prediction of a number of oil spill samples as well as weathered samples that closely resemble samples collected by first responders. KW - Oil spills KW - Fluorescence KW - PCA KW - Petroleum KW - Rapid test KW - Portable PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595442 DO - https://doi.org/10.1021/acsestwater.3c00648 VL - 4 IS - 2 SP - 621 EP - 627 PB - American Chemical Society (ACS) AN - OPUS4-59544 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Kohlhoff, Harald A1 - Neumann, Patrick P. A1 - Rudolph, Michael A1 - Schoppa, André A1 - Storm, Sven-Uwe A1 - Szczepaniak, Mariusz T1 - Auswirkungen von Behälterversagen bei alternativen PKW-Antrieben - Teil 3: Auswirkungen des Versagens von 11-kg-Propangasbehältern im Feuer N2 - In Deutschland gibt es eine große Anzahl von Kraftfahrzeugen, die mit alternativen Antrieben (z. B. LPG (Liquefied Petroleum Gas), CNG (Compressed Natural Gas)) ausgerüstet sind. In zahlreichen Großversuchsserien untersucht die Bundesanstalt für Materialforschung und -prüfung (BAM) im Rahmen des internen Forschungsprojekts CoFi-ABV (Complex Fires – Auswirkungen von Behälterversagen) die Auswirkungen beim Versagen der Treibstoffbehälter dieser alternativen Antriebe. Ziel dieser Untersuchungen ist eine ganzheitliche Auswirkungsbetrachtung, um die Risiken für Feuerwehren und Rettungskräfte besser abschätzen zu können. Im Vorfeld zu den Versuchen für LPG- und CNG-Tanks wurden in einer weiteren Versuchsserie 15handelsübliche 11-kg-Propangasflaschen ohne Sicherheitseinrichtung unterfeuert. Alle 15 Behälter haben – wie zu erwarten war – versagt. Neben den Zustandsdaten des Behälters zum Versagenszeitpunkt (Temperatur des Behältermantels, Innendruck und -temperatur) wurden die Auswirkungen auf die Umgebung hinsichtlich Druckwirkung und Fragmentierung (Anzahl, Masse, Distanz, Richtung) dokumentiert. KW - Behälterversagen KW - Gassicherheit KW - Feuerwehr KW - Propan KW - Auswirkungsbetrachtung PY - 2017 SN - 2191-0073 VL - 7 IS - 11/12 SP - 25 EP - 32 PB - Springer-VDI-Verlag GmbH & Co. KG CY - Düsseldorf AN - OPUS4-43270 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Kohlhoff, Harald A1 - Krüger, Simone A1 - Neumann, Patrick P. A1 - Rudolph, Michael A1 - Schoppa, André A1 - Storm, Sven-Uwe A1 - Szczepaniak, Mariusz T1 - Experimental investigation of consequences of LPG vehicle tank failure under fire conditions N2 - In case of a vehicle fire, an installed LPG (liquefied petroleum gas) tank with a malfunctioning safety device poses severe hazards. To investigate the consequences in case of tank failure, we conducted 16 tests with toroidal shaped LPG vehicle tanks. Three tanks were used for a Hydraulic Burst Test under standard conditions. Another three tanks were equipped with a statutory safety device and were subjected to a gasoline pool fire. The safety device prevented tank failure, as intended. To generate a statistically valid dataset on tank failure, ten tanks without safety devices were exposed to a gasoline pool fire. Five tanks were filled to a level of 20 %; the re-maining five were filled to a level of 100 %. In order to gain information on the heating process, three tem-perature readings at the tank surface, and three nearby flame temperatures were recorded. At distances of l = (7; 9; 11) m to the tank, the overpressure of the shock wave induced by the tank failure and the unsteady tem-peratures were measured. All ten tanks failed within a time of t < 5 min in a BLEVE (boiling liquid expanding vapor explosion). Seven of these resulted directly in a catastrophic failure. The other three resulted in partial failure followed by catastrophic failure. A near field overpressure at a distance of l = 7 m of up to p = 0.27 bar was measured. All ten tests showed massive fragmentation of the tank mantle. In total, 50 fragments were found. These 50 fragments make-up 88.6 % of the original tank mass. Each fragment was georeferenced and weighed. Fragment throwing distances of l > 250 m occurred. For the tanks with a fill level of 20 %, the average number of fragments was twice as high as it was for the tanks that were filled completely. KW - Blast wave KW - BLEVE KW - Consequences KW - Explosion KW - LPG PY - 2018 UR - https://authors.elsevier.com/a/1XnFv_Ld32ewKu DO - https://doi.org/10.1016/j.jlp.2018.09.006 SN - 0950-4230 VL - 56 SP - 278 EP - 288 PB - Elsevier CY - Kidlington - Oxford AN - OPUS4-46238 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Kohlhoff, Harald A1 - Neumann, Patrick P. A1 - Storm, Sven-Uwe A1 - Rudolph, Michael A1 - Schoppa, André A1 - Sczepaniak, Mariusz T1 - Mobile gas cylinders in fire: Consequences in case of failure N2 - Commercial, off-the shelf propane cylinders are subjected to high safety regulations. Furthermore, those cylinders are equipped with safety devices like pressure relief valves (PRV). Despite these regulations and safety measures, a failure of the container is possible if exposed to an intense fire. The result of this is severe hazard for users, rescue forces and infrastructure. Within the framework of a destructive test series, 15 identical propane cylinders, without pressure relief devices, were exposed to an intensive fire in horizontal position until failure. Each cylinder was filled with a mass of m =11 kg of liquid propane. Three different fire sources were used (wood, petrol, propane). The experiments revealed the failure of all cylinders in a time period t < 155 s. The failure lead to a fragmentation into several major parts with throwing distances of up to l =262 m. In all trials, the temperature of the cylinder wall (top, side, bottom), of the liquid phase inside and of the surrounding fire (top, side, bottom) was recorded. In addition, the inner cylinder pressure and the induced overpressure of the blast wave after the failure were recorded. Overpressures of up to p=0.27 bar were recorded close to the cylinder (l =5 m). All tests were documented by video from several positions (general view, close-up, high-speed 5000 fps). This test series creates the basis for further experimental studies in the field of alternative fuels for vehicles. The aim of this test series is to assess and analyse the consequences of the failure of gas vessels (for LPG, CNG, CGH2) in the aftermath of severe incidents. KW - Explosion KW - Gas cylinders KW - Consequences PY - 2017 UR - http://www.sciencedirect.com/science/article/pii/S037971121730098X DO - https://doi.org/10.1016/j.firesaf.2017.05.006 SN - 0379-7112 SN - 1873-7226 VL - 91 SP - 989 EP - 996 PB - Elsevier AN - OPUS4-40550 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krentel, Daniel A1 - Tschirschwitz, Rico A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Kohlhoff, Harald A1 - Mair, Georg W. A1 - Neumann, Patrick P. A1 - Rudolph, Michael A1 - Schoppa, André A1 - Storm, Sven-Uwe A1 - Szczepaniak, Mariusz T1 - Auswirkungen von unfallbedingtem Behälterversagen bei alternativen Pkw-Antrieben - Teil 1: Problemstellung, Stand der Technik und Voruntersuchungen N2 - Flüssige und komprimierte Gase sind in Deutschland, Europa und der Welt vielfältig als alternative Kraftstoffe im Einsatz. Diese werden unter teilweise hohem Druck in robusten Behältern an Bord gespeichert. Ein Versagen des Treibstoffbehälters im Schadensfall sollen verschiedene Sicherheitseinrichtungen, auch bei einem eventuell unfallbedingt auftretenden Fahrzeugbrand, verhindern. Sind diese Sicherheitseinrichtungen unfallbedingt beschädigt oder liegen die Belastungen dieser Einrichtung außerhalb ihres Auslegungsbereichs, ist ein Versagen des Behälters dennoch möglich. Dadurch kann es zur Bildung eines explosionsfähigen Brennstoff-Luft-Gemischs mit den entsprechenden Folgen für Fahrgäste, Einsatzkräfte und Umfeld kommen. Die Bundesanstalt für Materialforschung und -prüfung (BAM) untersucht im Forschungsprojekt "CoFi-ABV" mit umfangreichen zerstörenden Versuchsreihen im Realmaßstab die Folgen des unfallbedingten Versagens von Behältern für alternative Kraftstoffe und Maßnahmen zur Reduktion dieser Folgen im Rahmen einer ganzheitlichen Auswirkungsbetrachtung. Dieser Beitrag ist der Start einer Reihe und soll die Problemstellung sowie die Projektinhalte umfassend erläutern. KW - Alternative Antriebe KW - Alternative Kraftstoffe KW - Behälterversagen KW - Fahrzeugbrand PY - 2016 SN - 2191-0073 VL - 6 IS - 9 SP - 39 EP - 46 PB - Springer-VDI-Verlag CY - Düsseldorf AN - OPUS4-37360 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Patrick P. A1 - Kohlhoff, Harald A1 - Hüllmann, Dino A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Krentel, Daniel A1 - Mair, Georg W. A1 - Rudolph, Michael A1 - Schoppa, André A1 - Szczepaniak, Mariusz A1 - Storm, Sven-Uwe A1 - Tschirschwitz, Rico T1 - Auswirkungen von Behälterversagen bei alternativen PKW-Antrieben - Teil 2: UAV-basierte Fernerkundung von Gaswolken N2 - Verkehrsunfälle unter Beteiligung von Fahrzeugen mit alternativen Kraftstoffen wie LPG („Autogas“, Liquefied Petroleum Gas), CNG (Compressed Natural Gas, komprimiertes Erdgas) oder CGH2 (Compressed Gas Hydrogen, komprimierter Wasserstoff), bergen neue, komplexe Risiken für Passagiere, Einsatzkräfte und deren Umfeld. Im Rahmen des Projektes „CoFi-ABV“ beschäftigt sich die Bundesanstalt für Materialforschung und -prüfung (BAM) unter Berücksichtigung komplexer Brand- und Explosionsszenarien mit einer ganzheitlichen Betrachtung der Auswirkungen des unfallbedingten Versagens von Gasbehältern für alternative Kraftstoffe. Ein wichtiger Teil des Forschungsvorhabens umfasst Entwicklung, Aufbau und Validierung einer unbemannten Flugplattform (Unmanned Aerial Vehicle, UAV) zur Ferndetektion von Gaswolken. Für das sogenannte gassensitive Mini-UAV wird ein robuster Open-Path-Gasdetektor auf einer Sensorbewegungsplattform in Form eines modifizierten Kamera-Gimbals, integriert. Ziel ist es, ein leistungsfähiges und robustes Werkzeug zu entwickeln, welches Einsatzkräften im Falle eines Unfalls als Hilfe zur Abschätzung der Gefahr durch Gaswolken, ihrer Ausbreitung und der notwendigen Absperrbereiche zur Verfügung steht. Dieser Artikel ist der zweite der Reihe und legt, nach Projektvorstellung im ersten Teil, nun den Schwerpunkt auf das gassensitive Mini-UAV. KW - UAV KW - Fernerkundung KW - Open-Path-Gasdetektor KW - Alternative Antriebe/Kraftstoffe KW - Behälterversagen PY - 2016 SN - 2191-0073 VL - 6 IS - 11/12 SP - 23 EP - 28 PB - Springer-VDI-Verlag CY - Düsseldorf AN - OPUS4-38517 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -