TY - JOUR A1 - Qiao, Linan A1 - Neumann, Martin A1 - Komann, Steffen A1 - Ballheimer, Viktor T1 - Dynamic and quasi-static FE calculation of impact from 9 metre drop of spent fuel transport cask JF - Packaging, transport, storage & security of radioactive materials (RAMTRANS) N2 - The drop from 9 m height onto a rigid target is one of the required proofs of safety for packages of radioactive materials. Direct dynamic finite element method (FEM) calculations and combined two step analytical quasi-static finite element (FE) calculations are both applied for the simulation of a 9 m drop test. This paper gives a comparative example of both approaches for the 9 m side drop simulation of the spent fuel transport cask with wood filled impact limiter. The model for dynamic FEM consists of cask body and impact limiter. Detailed material properties and geometry descriptions from each component of the impact limiter are required. The results (stress fields in the cask body) are obtained directly from the calculation. The combined method provides as intermediate results the force-deformation characteristic of impact limiter. The maximum impact limiter force determined by the law of energy conservation during the drop is then - in a second step - applied on the cask body in a quasi-static FE model in order to calculate the stresses. In this paper, the rigid body deceleration and the maximum stress in the middle of the cask body are used for the comparison between the dynamic FEM and the combined method. Similar maximum rigid body deceleration-time curves were obtained by both methods for the horizontal 9 m free fall. Concerning the stress in the cask body the dynamic FEM results oscillate about values calculated by the combined quasi-static approach. If the combined quasi-static approach is used in the safety assessment of a cask, a suitable factor has to be applied on its results to take into account the additional dynamic effects. KW - Drop test KW - Spent fuel transport cask KW - Finite element calculation KW - Dynamic simulation KW - Impact limiter KW - Wood PY - 2009 DO - https://doi.org/10.1179/174650909X12553336148026 SN - 1746-5095 SN - 1746-5109 SN - 0957-476X VL - 20 IS - 4 SP - 174 EP - 178 PB - Ramtrans Publ. CY - Ashford AN - OPUS4-20819 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dreßler, Martin A1 - Nofz, Marianne A1 - Dörfel, Ilona A1 - Saliwan Neumann, Romeo T1 - Diffusion of Cr, Fe, and Ti ions from Ni-base alloy inconel-718 into a transition alumina coating JF - Thin solid films N2 - Heat treating metals at high temperatures trigger diffusion processes which may lead to the formation of oxide layers. In this work the diffusion of Cr, Fe and Ti into an alumina coating applied to Inconel-718 is being investigated. Mass gain measurements, UV–vis spectroscopy and transmission electron microscopy were applied in order to study the evolution of the diffusion process. It was found that mainly Cr as well as minor amounts of Fe and Ti are being incorporated into the alumina coating upon prolonged heat treatment at 700 °C. It could be shown that alumina coatings being void of Cr have the same oxidation related mass gain as uncoated samples. However, incorporation of Cr into the alumina coating decreased their mass gain below that of uncoated substrates forming a Cr oxide scale only. KW - Diffusion KW - UV–vis spectroscopy KW - Transmission electron microscopy KW - Alumina coatings KW - Sol-gel deposition PY - 2012 DO - https://doi.org/10.1016/j.tsf.2012.02.006 SN - 0040-6090 VL - 520 IS - 13 SP - 4344 EP - 4349 PB - Elsevier CY - Amsterdam AN - OPUS4-25830 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Komann, Steffen A1 - Neumann, Martin A1 - Ballheimer, Viktor A1 - Wille, Frank A1 - Weber, Mike A1 - Qiao, Linan A1 - Droste, Bernhard T1 - Mechanical assessment within type B packages approval: application of static and dynamic calculation approaches JF - Packaging, transport, storage & security of radioactive materials (RAMTRANS) N2 - This paper demonstrates exemplarily how numerical and experimental approaches can be combined reasonably in mechanical assessment of package integrity according to the IAEA regulations. The paper also concentrates on the question about how static mechanical approaches can be applied, and what their problems are in relation to dynamic calculation approaches. Under defined impact tests, which represent accident transport conditions, the package has to withstand impact loading, e.g. resulting from a 9 m free drop onto an unyielding target in sequence with a 1 m puncture drop test. Owing to the local character of the interaction between the puncture bar and the cask body, it is possible to develop a dynamic numerical model for the 1 m puncture drop which allows an appropriate simulation of the interaction area. Results from existing experimental drop tests with prototype or small scale cask models can be used for verification and validation of applied analysis codes and models. The link between analysis and experimental drop testing is described exemplarily by considering a regulatory 1 m puncture bar drop test onto the cask body of a recently approved German high level waste transport package. For the 9 m drop test of the package, it is difficult to develop a dynamic numerical model of the package due to the complexity of the interaction between cask body, impact limiters and unyielding target. Dynamic calculations require an extensive verification with experimental results. The simulation of a 9 m drop of a package with impact limiters is thereby often more complex than the simulation of a 1 m puncture drop onto the cask body. A different approximation method can be applied for the consideration of dynamic effects on the impact loading of the package. In a first step, maximum impact force and rigid body deceleration of the cask body during the impact process can be calculated with simplified numerical tools. This rigid body deceleration can subsequently be applied on a verified static numerical model. Dynamic effects, which cannot be covered by the static numerical analysis, have therefore to be considered by using an additional dynamic factor. The paper describes this approach exemplarily for a 9 m horizontal drop of a typical spent fuel cask design. KW - Package assessment KW - Package KW - Packaging KW - Structural analysis PY - 2011 DO - https://doi.org/10.1179/1746510911Y.0000000012 SN - 1746-5095 SN - 1746-5109 SN - 0957-476X VL - 22 IS - 4 SP - 179 EP - 183 PB - Ramtrans Publ. CY - Ashford AN - OPUS4-26448 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Musolff, André A1 - Müller, Karsten A1 - Neumann, Martin A1 - Kadji, Arsène Brice A1 - Droste, Bernhard T1 - Results of full scale CONSTOR® V/TC prototype 9 m horizontal drop test JF - Packaging, transport, storage & security of radioactive materials (RAMTRANS) KW - Drop testing KW - Impact limiter KW - Finite element method KW - Full scale cast PY - 2008 DO - https://doi.org/10.1179/174651008X382951 SN - 1746-5095 SN - 1746-5109 SN - 0957-476X VL - 19 IS - 4 SP - 228 EP - 232 PB - Ramtrans Publ. CY - Ashford AN - OPUS4-18625 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Martin A1 - Herter, Jürgen A1 - Droste, Bernhard A1 - Hartwig, S. T1 - Compressive behaviour of axially loaded spruce wood under large deformations at different strain rates JF - European journal of wood and wood products N2 - Impact limiting components of packages for the transport of radioactivematerials are often designed as wood filled steel constructions. Wood absorbs major part of the impact energy in order to minimise the impact load acting upon the containment. Dynamic impact experiments with wood filled impact limiters showed different crushing mechanisms for axially loaded wood depending on their lateral constraint. Tests on spruce wood samples (Picea abies) were performed in order to clarify the influence of strain rate from static to 30 s-1 on a) compression strength, b) stress at a global strain level of 50%, and c) energy absorption capacity at 50% deformation, including statistical evaluation of the results. Results were as follows: strain rate increase led to significantly higher compression strength, stress and strain energy at a strain level of 50%. Lateral strain restriction had no effect on compression strength; it had a significant effect on stress and strain energy at strain level of 50%. Therefore, the definition of a general yield curve for wood under large deformations is not possible, the yield curve has to be chosen taking into account lateral constraints. KW - Compression KW - Wood KW - Spruce KW - Picea abies KW - Impact PY - 2011 DO - https://doi.org/10.1007/s00107-010-0442-x SN - 0018-3768 VL - 69 IS - 3 SP - 345 EP - 357 PB - Springer CY - Berlin ; Heidelberg AN - OPUS4-22980 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Patrick P. A1 - Kohlhoff, Harald A1 - Hüllmann, Dino A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Dzierliński, M. A1 - Lilienthal, A. J. A1 - Bartholmai, Matthias T1 - Aerial-based gas tomography – from single beams to complex gas distributions JF - European Journal of Remote Sensing N2 - In this paper, we present and validate the concept of an autonomous aerial robot to reconstruct tomographic 2D slices of gas plumes in outdoor environments. Our platform, the so-called Unmanned Aerial Vehicle for Remote Gas Sensing (UAV-REGAS), combines a lightweight Tunable Diode Laser Absorption Spectroscopy (TDLAS) gas sensor with a 3-axis aerial stabilization gimbal for aiming at a versatile octocopter. While the TDLAS sensor provides integral gas concentration measurements, it does not measure the distance traveled by the laser diode’s beam nor the distribution of gas along the optical path. Thus, we complement the set-up with a laser rangefinder and apply principles of Computed Tomography (CT) to create a model of the spatial gas distribution from a set of integral concentration measurements. To allow for a fundamental ground truth evaluation of the applied gas tomography algorithm, we set up a unique outdoor test environment based on two 3D ultrasonic anemometers and a distributed array of 10 infrared gas transmitters. We present results showing its performance characteristics and 2D plume reconstruction capabilities under realistic conditions. The proposed system can be deployed in scenarios that cannot be addressed by currently available robots and thus constitutes a significant step forward for the field of Mobile Robot Olfaction (MRO). KW - Aerial robot olfaction KW - Mobile robot olfaction KW - Gas tomography KW - TDLAS KW - Plume PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-487843 DO - https://doi.org/10.1080/22797254.2019.1640078 SP - 1 EP - 16 PB - Taylor & Francis CY - London AN - OPUS4-48784 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 - 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 JF - Journal of Loss Prevention in the Process Industries 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 JF - Fire Safety Journal 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 - 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, Miachael A1 - Schoppa, André A1 - Storm, Sven-Uwe A1 - Szczepaniak, Mariusz ED - Aga, Diana ED - Daugulis, Andrew ED - Li Puma, Gianluca ED - Lyberatos, Gerasimos ED - Tay, Joo Hwa ED - Lima, Éder Claudio T1 - Hazards from failure of CNG automotive cylinders in fire JF - Journal of Hazardous Materials N2 - Compressed natural gas (CNG) is a widely used automotive fuel in a variety of countries. In case of a vehicle fire where the safety device also malfunctions, a failure of the CNG automotive cylinder could occur. Such a cylinder failure is associated with severe hazards for the surrounding environment. Firstly, a comprehensive analysis is given below, summarizing various accidents involving CNG automotive cylinders and their consequences. In an extensive experimental program, 21 CNG automotive cylinders with no safety device were tested. Of the 21, burst tests were carried out on 5 Type III and 5 Type IV cylinders. Furthermore, fire tests with 8 Type III and 3 Type IV cylinders were conducted. Apart from cylinder pressure, inner temperature and cylinder mantle temperature, the periphery consequences, such as nearfield blast pressure and fragmentation are documented. The maximum measured overpressure due to a Type III cylinder failure was p = 0.41 bar. Each traceable fragment was georeferenced. All-in-all, fragment throw distances of d > 300 m could be observed. As one key result, it can be stated that the tested Type IV CNG cylinders showed less critical failure behavior then the Type III cylinders under fire impingement. KW - CNG KW - Composite cylinder KW - Gas cylinder KW - Tank failure KW - Fragments PY - 2019 DO - https://doi.org/10.1016/j.jhazmat.2018.12.026 SN - 0304-3894 SN - 1873-3336 VL - 367 SP - 1 EP - 7 PB - Elsevier CY - New York City, New York, USA AN - OPUS4-47135 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Martin A1 - Gleim, Tobias A1 - Gradt, Thomas T1 - Friction coefficients for wood-wood and wood-steel high pressure contact under temperatures between -40 °C and 90 °C JF - Tribologie + Schmierungstechnik N2 - Wood is widely used in impact limiters of Transport casks for radioactive material. Encapsulated by an outer and inner Steel structure, spruce wood is offen applied in layers of altemating direction. The friction at the interfaces between these layers is of crucial importance for the impact and energy absorption e.g., at an accidental impact of a cask against a hard component. In order to get detailed Information for corresponding numerical calculations, in this study the friction coefficient for the combinations wood-wood and wood-steel was measured in the temperature ränge between -40 °C and 90 °C according to the relevant stress conditions for such casks. Results show decreasing friction with increasing temperature, ranging from 0.43 at -40 °C to 0.22 for 90 °C for wood-steel combinations and from 0.3 at -40 °C to 0.24 at 90 °C to for a wood-wood combination. KW - Wood KW - Friction KW - Transport cask KW - Radioactive material PY - 2023 DO - https://doi.org/10.24053/TuS-2023-0007 SN - 0724-3472 VL - 70 IS - 2 SP - 5 EP - 12 PB - expert verlag AN - OPUS4-57787 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -