TY - JOUR A1 - Hurtado-Hurtado, G. A1 - Morales-Velazquez, L. A1 - Valtierra-Rodríguez, M. A1 - Otremba, Frank A1 - Jáuregui-Correa, J. C. T1 - Frequency Analysis of the Railway Track under Loads Caused by the Hunting Phenomenon JF - Mathematics N2 - Hunting is a potentially dangerous phenomenon related to the lateral oscillation of the wheels that impacts the rails and causes the wear of the infrastructure’s components. Therefore, the analysis and timely detection of hunting can lead to the application of corrective maintenance tasks, reducing damages, and costs and even derailments as a result. In this work, the vibration response of a finite element model of a rail with hunting-induced loads by a single wheel is analyzed in three directions: longitudinal, lateral, and vertical. The contact patch forces are calculated by means of Simpack® using the Kalker linear theory and the contact Hertz theory. The system is solved by using the Newmark-_ approach. The results of the deflection and vibration analysis, following the proposed methodology, show how the different characteristics of the loads impact the rail. KW - Continuous wavelet transform KW - Empirical mode decomposition KW - Finite element method KW - Frequency analysis KW - Hunting phenomenon KW - Mechanical modelling KW - Rail vibrations PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-551517 UR - https://www.mdpi.com/2227-7390/10/13/2286/htm# DO - https://doi.org/10.3390/math10132286 VL - 10 IS - 13 SP - 1 EP - 17 PB - MDPI AN - OPUS4-55151 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Romero Navarrete, J. A. A1 - Otremba, Frank A1 - Lozano Guzmán, A. A. T1 - Experimental-theoretical modelling of the lateral sloshing in rail tankers JF - International Journal of Heavy Vehicle Systems N2 - The objective of this paper is to describe and to validate a simplified pendulum-analogy model to simulate the interaction of a liquid cargo with ist carrying vehicle. The resulting testing rig consists of a rectangular container, spring supported on a two wheelset-bogie having a scale down of 1/10 with respect to a full-size equipment. The testing rig is used to validate a simple pendulum-based, simplified three degree-of-freedom mathematical model of the response of a partially filled container to lateral accelerations. The length of the pendulum is set according to validated methodologies. The resulting mathematical scheme reveals a high correlation with the experimental output, on the order of 99%, while some other performance measures, related to the peak forces and the range of variation of the wheel-rail forces, also show good concordance with the experimental results. KW - Sloshing KW - Rail tankers KW - Pendulum analogy KW - Experimental modelling KW - Mechanical fatigue PY - 2021 DO - https://doi.org/10.1504/ijhvs.2021.117504 VL - 28 IS - 3 SP - 435 EP - 454 AN - OPUS4-53101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Romero Navarrete, J. A. A1 - Otremba, Frank A1 - Lozano Guzmán, A. A. T1 - Liquid cargo effect on load transfer under orthogonal accelerations JF - International journal of heavy vehicle systems N2 - A methodology is proposed for the experimental analysis of the liquid cargo effect under combined orthogonal accelerations. To simultaneously subject the vehicle-cargo system to longitudinal and lateral accelerations, the vehicle is set obliquely on a tilt table. The experimental outputs suggest that there is a significant effect of the liquid cargo on the lateral load transfer ratio (LTR), on the order of 20%, which is attributable to the resulting shifting of the liquid cargo’s centre of gravity. That is, the peak LTR values due exclusively to sloshing were not significant, in such a way that the liquid cargo would only pose a safety risk under a steady acceleration input. Also, the inverse of the product of the magnitude of the acceleration times the free surface length, correlates with the liquid cargo effect. That is, the magnitude of the input acceleration is not fully determinant for greater load transfers. KW - Sloshing KW - Liquid cargo KW - Cargo shifting KW - Lateral load transfer KW - Braking in a turn manoeuvre KW - Experimental methods KW - Transport safety PY - 2022 DO - https://doi.org/10.1504/ijhvs.2022.127011 SN - 1744-232X VL - 29 IS - 3 SP - 213 EP - 226 PB - Inderscience Enterprises CY - Geneva AN - OPUS4-56016 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jauregui-Correa, J. C. A1 - Morales-Velazquez, L. A1 - Otremba, Frank A1 - Hurtado-Hurtado, G. T1 - Method for predicting dynamic loads for a health monitoring system for subway tracks JF - Frontiers in mechanical engineering N2 - This paper presents a method for processing acceleration data registered on a train and determining the health condition of a subway’s substructure. The acceleration data was converted into a dynamic deformation by applying a transfer function defined using the Empirical Mode Decomposition Method. The transfer function was constructed using data produced on an experimental rig, and it was scaled to an existing subway system. The equivalent deformation improved the analysis of the dynamic loads that affect the substructure of the subway tracks because it is considered the primary load that acts on the track and substructure. The acceleration data and the estimated deformations were analyzed with the Continues Wavelet Transform. The equivalent deformation data facilitated the application of a health monitoring system and simplified the development of predictive maintenance programs for the subway or railroad operators. This method better identified cracks in the substructure than using the acceleration data. KW - Health monitoring KW - Transfer function KW - Railroad KW - Substructure failures KW - Dynamic loads PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-557480 DO - https://doi.org/10.3389/fmech.2022.858424 SN - 2297-3079 VL - 8 SP - 1 EP - 16 PB - Frontiers Media CY - Lausanne AN - OPUS4-55748 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Borch, Jörg A1 - Otremba, Frank T1 - Der neue Jetfire-Prüfstand der BAM JF - Technische Sicherheit N2 - Die BAM – Bundesanstalt für Materialforschung und -prüfung führt schon seit vielen Jahren auf zwei Brand- prüfständen Brandprüfungen z.B. an Transport- und Lagerbehältern für radioaktive Stoffe oder zur Prüfung von Brandschutzbeschichtungen durch. Als Brandmedium wird auf diesen Prüfständen Flüssiggas (Propan- Butan-Gemisch C) eingesetzt, mit dem die Prüfobjekte simulierten Unfallfeuern ausgesetzt werden. Mit dem neuen Jetfire – Prüfstand der BAM können seit Anfang 2018 diverse Belastungsszenarien nach den Anforde- rungen der ISO22899-1:2007 [1] simuliert werden. KW - Jetfire KW - Prüftstand PY - 2018 UR - https://www.technische-sicherheit.de/ts/article.php?data[article_id]=89195 SN - 2191-0073 VL - 8 IS - 4 SP - 25 EP - 27 PB - Springer-VDI-Verl. CY - Düsseldorf AN - OPUS4-44814 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Romero-Navarrete, José A. A1 - Otremba, Frank T1 - A testing facility to assess railway car infrastructure damage JF - International Journal of development and intergration N2 - Wheel forces generate stresses in the rail as a function of several vehicle and infrastructure characteristics and operating conditions. The different components of the wheel forces develop strains in the rail which contain an elastic and hysteretic (irreversible) components. The irreversible deformations of the rail would be associated with locomotive energy losses. In this paper, a testing facility is proposed to indirectly characterize the level of stresses in the rail, in terms of the energy that is lost during tuming maneuvers. Different potentially influential factors are considered, including the friction at the Center plate, the wheelbase length, the distance between bogies and the radius of the curved track. The change in the potential energy during a U-turn displacement is measured. In this respect, an experimental model under this operating principle, aimed at validating such a principle of Operation, reveals a significant effect of the friction at the center plate on the energy lost during turning maneuvers, and consequently, on the level of stresses in the rail. T2 - COMPRAIL 2020 - 17th International Conference on Railway Engineering Design & Operation 2020 CY - Online meeting DA - 01.07.2020 KW - Energy losses in transportation KW - Experimental methods KW - Friction energy KW - Rail damage KW - Turning forces KW - Wheel forces PY - 2020 DO - https://doi.org/10.2495/TDI-V4-N2-142-151 SN - 2058-8305 VL - 4 IS - 2 SP - 142 EP - 151 PB - WitPress AN - OPUS4-51125 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bradley, Ian A1 - Scarponi, G. E. A1 - Otremba, Frank A1 - Birk, A. M. T1 - An overview of test standards and regulations relevant to the fire testing of pressure vessels JF - Process safety and environmental protection N2 - Fire exposure of storage and transportation vessels of hazardous materials (including pressure liquefied gases) can result in BLEVEs and other high-consequence incidents with large societal and economic impacts. To reduce risk most countries have numerous regulations, codes of practice and guidance notes covering the design, operation and maintenance of vessels and thermal protection systems. Yet despite such regulations there remains no internationally accepted fire test procedure for pressure vessel and accompanying thermal protection systems that is capable of meeting a range of regulatory requirements. This paper considers some of the regulations in place in the western world and considers the origin of these based on large and medium-scale testing conducted to date. It examines conditions found in these tests to propose a set of recommendations on which to base a standard method of test. These recommendations are proposed as being representative of a credible large pool fire scenario that may occur. KW - LPG KW - Pressure vessel KW - Test KW - BLEVE KW - Fire PY - 2021 DO - https://doi.org/10.1016/j.psep.2020.07.047 SN - 0957-5820 VL - 145 SP - 150 EP - 156 PB - Elsevier CY - Amsterdam AN - OPUS4-51139 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Romero-Navarrete, José A. A1 - Otremba, Frank T1 - A method to assess the gravity response efficiency of a truck JF - International journal of environmental science N2 - In spite that transport activities do not represent the biggest contributor of pollutants emissions, their reduction has been a priority as some other externalities are associated to such emissions and to the transport itself. A crucial element to characterize the behavior of the vehicles against the environment are the losses that such vehicles exhibit in a passive way, that is, without any involvement of power conditions. The energy loses due to the rolling, the drag and to the friction in mechanical components, have been assessed so far in terms of the stopping acceleration when the vehicle idles on a ramp. However, such a testing procedure produces some uncertainties due to the dynamic conditions that are considered. To avoid such critical limitations, in this paper a testing procedure and facility are proposed, which are based on static conditions of the vehicle at the initiation and at the ending of the test, which are assumed to provide a better reliability to the testing. Some preliminary theoretical analysis should be made in order to validate the operational principles proposed herein for such testing facility. KW - Road tankers KW - Energy efficiency KW - Environmental assessment KW - Gravity response KW - Transportation energy KW - Rolling resistance KW - Drag resistance PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511530 UR - https://www.iaras.org/iaras/home/caijes/a-method-to-assess-the-gravity-response-efficiency-of-a-truck SN - 2367-8941 VL - 5 SP - 213 EP - 219 PB - IARAS CY - Sofia AN - OPUS4-51153 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Romero-Navarrete, José A. A1 - Otremba, Frank A1 - Lozano Guzman, A. A. T1 - Estimation of the effect of the driving style on pollutants emission by heavy trucks JF - International journal of environmental science N2 - Different approaches have been attempted so far to reduce fuel consumption and linked pollutants, including vehicle equipment and design, with rational driving style being recognized as a potential source of fuel savings. However, no specific methodology had been suggested so far to assess fuel economy of driving other than the fuel consumed itself. In this paper, the Standard deviation of driving acceleration has been found to be directly associated to fuel consumption, so that the less dispersion of the driving acceleration, produces the lower fuel consumptions and emissions. Such metric could be thus used to assess driving style. KW - Driving style KW - Fuel consumption KW - Stored energy KW - GPS data KW - Simulation KW - Particle emissions PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511540 UR - https://www.iaras.org/iaras/home/caijes/estimation-of-the-effect-of-the-driving-style-on-pollutants-emission-by-heavy-trucks SN - 2367-8941 VL - 5 SP - 220 EP - 226 PB - IARAS CY - Sofia AN - OPUS4-51154 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Romero-Navarrete, José A. A1 - Otremba, Frank A1 - Hurtado-Hurtado, G. ED - Romero-Navarrete, José A. T1 - A Conceptual Design of a Self-Centering Centre Plate JF - International Journal of Aerospace and Mechanical Engineering N2 - Turning maneuvers originate higher forces exerted on the rail and the loss of locomotive energy, at a rate that is function of several parameters that influence the magnitude of the developed horizontal wheel-rail forces, including the friction at the centre plate and the bogie´s yaw stiffness. However, such a friction at the contact surfaces of the centre plate is needed to mitigate the Hunting phenomenon when the train moves on straight track segments. In this paper, a self-centering centre plate is proposed, consisting of a lubricated centre plate, equipped with a spring- and damper-based self-centering mechanism. Simulation results of the proposed mechanism suggest that the energy performance in turns of a train car equipped with such self-centering centre plate is comparatively better, as the peak friction forces linked to the dry friction at the contact surfaces of current centre plate designs, are avoided. The assessment of the hunting performance of the proposed device in straight track segments is proposed as the continuation of this work. KW - Bogie´s yaw stiffness KW - Bogie´s yaw friction KW - Centre plate KW - Self-centering mechanism KW - Turning PY - 2020 UR - https://publications.waset.org/aerospace-and-mechanical-engineering SN - 1307-6892 VL - 14 IS - 9 SP - 376 EP - 382 AN - OPUS4-51241 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Otremba, Frank A1 - Romero-Navarrete, José A. T1 - A lowering friction treatment for railway materials JF - Advanced materials letters N2 - A facility is proposed in this paper to apply a selective carburizing process to the lateral faces of a railways´ head, aiming to increase its carbon content and to decrease the friction coefficient in case that the flange of the railway car wheel gets in contact with the rail during turning. Such a treatment would reduce the energy that is lost during the turning maneuvers performed by the vehicle, further improving the energy efficiency of the railway car. The facility consists of a furnace, which should be set next to the rails´ hot-rolling facility, in order to use the available enthalpy. The proposed furnace is equipped with what is necessary to avoid the decarbonization of the remaining rail material, based upon batteries of oxy-acetylene burners that are installed at the bottom of the furnace, on the opposite side to the carburizing surface. An experimental facility is necessary to validate the operational principles for the equipment proposed in this paper. On the other hand, a study should also be carried out to assess the effect of any rail welding process on the carburized surfaces. KW - Transport efficiency KW - Dry friction KW - Carburizing KW - Selective carburizing KW - Decarbonization KW - Furnace design PY - 2020 DO - https://doi.org/10.5185/amlett.2020.041498 VL - 11 IS - 4 SP - 2004198 PB - IAAM - VRBI Press AN - OPUS4-50958 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kutz, Philipp A1 - Otremba, Frank A1 - Werner, Jan T1 - Mechanical and Thermal Properties of Composite Material and Insulation for a Single Walled Tank for Cryogenic Liquids JF - Advanced Materials Letters N2 - This paper describes the testing methods used to determine the thermal properties of insulation materials and mechanical properties of materials used for the load-bearing structure for pressure tanks (up to 4 bar, relative) and cryogenic liquids (LNG, −166 °C to -157 °C at atmospheric pressure). Goal is to design a transportation tank that does not exceed 4 bars (relative) within 10 h, starting at atmospheric pressure. PUR-foam is a suitable material for the insulation. A 12,5 l small scale tank prototype reached 4 bar (relative) within 87 minutes, which is, regarding the influence of the size, a satisfying result. The mechanical properties change significantly at cryogenic temperatures. The bending modulus is similar at first, but decreases at a certain point by appr. 50 %. However, the maximum stress is much higher and could not be reached within this testing setup. T2 - 26th Assembly Advanced Materials Congress CY - Stockholm, Sweden DA - 10.06.2019 KW - GFRP KW - LNG KW - Lightweight design KW - Thermal properties KW - Mechanical prtoperties PY - 2020 DO - https://doi.org/10.5185/amlett.2020.011457 VL - 11 IS - 1 SP - 1 EP - 6 PB - VBRI Press AN - OPUS4-50216 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kutz, Philipp A1 - Werner, Jan A1 - Otremba, Frank T1 - Testing of Composite Material for Transport Tanks for LNG JF - Key Engineering Materials N2 - To reduce the emission of carbondyoxide (CO2) of combustion engines, liquefied natural gas (LNG) is used as an alternative fuel. LNG is transported via truck, ship or railway for long distances. Double walled stainless steel tanks are used for transportation, which are heavy and expensive. The vacuum insulation between the two walled structure ensures that the LNG stays liquid over the transportation time (boiling point of LNG: -162 ◦C). This causes a high temperature difference between the transported good and the ambient air. A simplified tank construction is used to reduce the weight and price of the tank. Instead of stainless steel, glass fiber reinforced plastic (GFRP) is used. The design is changed to a single walled construction with a solid insulation material outside on the GFRP structure. Goal of this work is the characterization of a suitable insulation material and configuration as well as the analysis of the mechanical properties of GFRP under cryogenic conditions. Several experiments are carried out. Numerical models of these experiments can then be used for parameter studies. KW - GFRP KW - Lightweight design KW - LNG PY - 2019 DO - https://doi.org/10.4028/www.scientific.net/KEM.809.625 SN - 1662-9795 VL - 809 SP - 625 EP - 629 PB - Trans Tech Publications Ltd. AN - OPUS4-48271 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Romero-Navarrete, José A. A1 - Otremba, Frank T1 - Vehicle’s components damage JF - Journal of Automobile Engineering N2 - The failure of vehicle’s suspension components has contributed to road crashes, while their defective operation can deteriorate the fuel efficiency of the vehicles. In this context, and when compared with solid cargo transporters, the road tankers would tend to produce larger roll forces during turning, as the curved shape of the liquid cargo container, shifts upwards the centre of gravity of the cargo. With reference to a rectangular cargo container representing the solid cargo situation, the increase in the position due to elliptical and circular tank shapes, can attain a value of 17% (100% fill, circular tank). In this study, experimental results comparing the lateral load transfer due to solid and liquid cargoes, indicate that the average force increase on the vehicle’s load-receiver side due to a liquid cargo, is 4.3%. To analyse the fullscale situation of both situations, that is, the higher position of the centre of gravity and the shifting of the liquid cargo, a simplified model is developed. The outputs from such a model when subjected to realistic operating conditions (speed and turning radius), suggest that the higher position of the centre of gravity due to using a non-rectangular cargo container generates an average force increase of 4.9% on the side receiving the load transfer. The incorporation of the effect of the liquid cargo, through the simple pendulum analogy, suggests that such an average increases to 6.76%, with a maximum of 8.35% in the case of the elliptical tank at 75% fill level. It is found that the average liquid cargo effect is 5.44%, which should be compared with the 4.3% of the experiments. Road tankers components would thus have a relatively shorter load cycle life than those of the solid cargo trucks. KW - Liquid cargo KW - Load transfer KW - Roll reactions KW - Experimental modelling KW - Pendulum-analogy PY - 2020 DO - https://doi.org/10.1177/0954407020960543 VL - 235 IS - 2-3 SP - 446 EP - 454 PB - Sage Journals AN - OPUS4-51386 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Otremba, Frank A1 - Romero-Navarrete, José A. A1 - Lozano Guzmán, A. A. T1 - Modelling of a Partially Loaded Road Tanker during a Braking-in-a-Turn Maneuver JF - Actuators N2 - This paper describes a theoretical model to simulate the effects of a sloshing cargo on the safety performance of a vehicle that performs a braking-in-a-turn maneuver when travels at a partial fill level. The fundamental assumption of the model consists of the superposition of the effects of two simplified mechanical-analogy models that represent a liquid cargo on a vehicle, including one for the roll motion and another one for the pitch motion. The distinctive characteristics of the mechanical models, however, is that they are based upon a validated formulation to establish the properties of the pendulum (length). The results suggest a small effect of the sloshing cargo on the braking efficiency of the cargo, while the load transfer is moderately affected. However, such results should be put into a perspective, according to which such small variations can represent the avoidance of a rear-end crash or a rollover. In this respect, a specialized ABS system could be considered to improve the performance of such kind of vehicles when performing such maneuvers. Validation of the proposed methodology should be performed as a continuation of this research effort. KW - ABS KW - Braking-in-a-turn maneuver KW - Cargo sloshing KW - Road tankers KW - Load transfer KW - Simulation KW - Turning maneuvers PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-456908 DO - https://doi.org/10.3390/act7030045 VL - 7 IS - 45 SP - 1 EP - 14 PB - MDPI CY - Basel AN - OPUS4-45690 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pötzsch, Sina A1 - Krüger, Simone A1 - Sklorz, Christian A1 - Borch, Jörg A1 - Hilse, Thilo A1 - Otremba, Frank T1 - The fire resistance of lightweight composite tanks depending on fire protection systems JF - Fire Safety Journal N2 - To save weight and resources lightweight tanks with complex geometries made of glass-fibre reinforced plastics (GFRP) are a promising innovation for the transportation of dangerous goods. To realise the use of polymer tanks for such applications, their fire safety must be guaranteed. This paper presents solutions to protect fibre-reinforced plastic tanks from fire. The fire resistance of six GFRP tanks with different fire protection systems was tested in an outdoor full-scale fire test facility according to the regulation stipulated in the ADR (European agreement concerning the national carriage of dangerous goods by road). All tanks feature a complex geometry and a holding capacity of 1100 litres. The fire protection systems are composed of specialised resins as well as two intumescent coatings. All systems had a protective impact. The best results were achieved by the epoxy based intumescent coating, which was able to prolong the time needed to reach 150 °C inside the tank by 20 min. The emergence of a temperature holding point inside the tank due to condensation effects was observed at temperatures around 100 °C. KW - Fire safety composite tanks PY - 2018 UR - https://www.sciencedirect.com/science/article/pii/S0379711218301644 DO - https://doi.org/10.1016/j.firesaf.2018.08.007 SN - 0379-7112 SN - 1873-7226 VL - 100 SP - 118 EP - 127 PB - Elsevier Ltd. AN - OPUS4-45697 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Borch, Jörg-Peter A1 - Otremba, Frank T1 - Jetfire-Prüfstand ergänzt die bereits vorhandenen Brandprüfstände JF - Technische Sicherheit N2 - Seit zehn Jahren führt die Bundesanstalt für Materialforschung und -prüfung (kurz: BAM) auf zwei Prüfständen Brandprüfungen z. B. an Transport-und Lagerbehältern für radioaktive Stoffe oder zur Prüfung von Brandschutzbeschichtungen durch. Als Brandmedium wird Flüssiggas (Propan-Butan-Gemisch C) eingesetzt, mit dem die Prüfobjekte simulierten Unfallfeuern ausgesetzt werden. Seit Anfang 2018 verfügt die BAM darüber hinaus auch über einen Jetfire-Prüfstand, der die Anforderungen der ISO 22899-1:2007 1) erfüllt. KW - JetFire KW - Prüfstand PY - 2018 SN - 2191-0073 SP - 28 EP - 30 PB - Springer-VDI-Verl. CY - Düsseldorf AN - OPUS4-46566 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fraňa, K. A1 - Attia, S. H. A1 - Otremba, Frank T1 - A numerical simulation of the filling process in the pressure bottle JF - International journal of mechanical engineering and robotics research N2 - A filling process of the pressure bottle used for the air storage was investigated by numerical simulations. During the filling process, the temperature was rising up to maximal value and after that started to decline. The good match was found between experimental and numerical results. In order to reproduce the experimental conditions, the process of the filling bottle was controlled by the pressure which varied in time. This filling strategy influenced furthermore the mass flow rate and the air flow velocity. Because of the geometrical symmetry, the simulation was calculated as an axisymmetric problem. KW - Filling procedere KW - Receptacle PY - 2018 UR - http://www.ijmerr.com/index.php?m=content&c=index&a=show&catid=162&id=997 DO - https://doi.org/10.18178/ijmerr.7.5.558-563 SN - 2278-0149 VL - 7 IS - 5 SP - 558 EP - 563 PB - IJMERR CY - Rowland Heights, CA, USA AN - OPUS4-46021 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Camplese, Davide A1 - Scarponi, Giordano Emrys A1 - Chianese, Carmela A1 - Hajhariri, Aliasghar A1 - Eberwein, Robert A1 - Otremba, Frank A1 - Cozzani, Valerio T1 - Modeling the performance of multilayer insulation in cryogenic tanks undergoing external fire scenarios JF - Process Safety and Environmental Protection N2 - Multilayer Insulation (MLI) is frequently used in vacuum conditions for the thermal insulation of cryogenic storage tanks. The severe consequences of the degradation of such materials in engulfing fire scenarios were recently evidenced by several large-scale experimental tests. In the present study, an innovative modelling approach was developed to assess the performance of heat transfer in polyester-based MLI materials for cryogenic applications under fire conditions. A specific layer-by-layer approach was integrated with an apparent kinetic thermal degradation model based on thermogravimetric analysis results. The modeling results provided a realistic simulation of the experimental data obtained by High-Temperature Thermal Vacuum Chamber tests reproducing fire exposure conditions. The model was then applied to assess the behavior of MLI systems for liquid hydrogen tanks in realistic fire scenarios. The results show that in intense fire scenarios degradation occurs rapidly, compromising the thermal insulation performances of the system within a few minutes. KW - Multilayer Insulation KW - Cryogenic Vessels KW - Liquefied Hydrogen KW - Liquefied Natural Gas KW - Safety KW - Fire PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599418 DO - https://doi.org/10.1016/j.psep.2024.04.061 SN - 0957-5820 VL - 186 SP - 1169 EP - 1182 PB - Elsevier B.V. AN - OPUS4-59941 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Camplese, D. A1 - Chianese, C. A1 - Scarponi, G. A1 - Eberwein, Robert A1 - Otremba, Frank A1 - Cozzani, V. T1 - Analysis of high temperature degradation of multi-layer insulation (MLI) systems for liquid hydrogen storage tanks JF - Chemical engineering transachtions N2 - The interest in hydrogen-based green energy is increasing worldwide, and the same is true for hydrogen-powered vehicles. Among the possible solutions to store hydrogen in such vehicles, cryogenic tanks equipped with multi-layer insulation (MLI) are the most promising to increase the amount of energy stored per unit volume. However, MLI is affected by severe deterioration when exposed to an external source of heat such as a fire following a car accident, leaving the tank unprotected and leading to failure in a relatively short time. In this work, a one-dimensional model to evaluate MLI thermal degradation when a liquid hydrogen tank is exposed to fire is presented. The relevance of taking MLI degradation into account when simulating the pressure increase due to external fire exposure is here demonstrated through the analysis of several case studies. The results show that MLI systems performance depletes within a few minutes of exposure to hydrocarbon poolfire. T2 - ICheaP 16 CY - Naples, Italy DA - 21.05.2023 KW - LH2 KW - MLI KW - Tiefkalt KW - Fire KW - Tank PY - 2023 SN - 2283-9216 VL - 2023 SP - 1 EP - 6 PB - AIDIC Servizi S.r.l. AN - OPUS4-57584 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hurtado-Hurtado, G. A1 - Morales-Velazquez, L. A1 - Otremba, Frank A1 - Jáuregui-Correa, J. C. T1 - Railcar Dynamic Response during Braking Maneuvers Based on Frequency Analysis JF - Applied Sciences N2 - The dynamic response of a vehicle during braking is influenced by the tangential forces developed at the wheel-rail’s contact surface. The friction coefficient affects the load transfer from the wheel’s tread to the vehicle. In this work, the vibrations of a scale-down railway vehicle are monitored during braking and their relationship with the friction coefficient between wheel and rail is found out. The vehicle is instrumented with encoders, accelerometers, and is controlled via Bluetooth. The tests are carried out with clean and friction-modified rails. The tangential forces transmitted from the wheel to the railcar’s body are visualized in time and frequency using a proposed correlation algorithm based on the outputs of the ContinuousWavelet Transform (CWT). The results demonstrate that tangential forces have a significant impact on railway vehicles under conditions of high friction coefficients and large creep values. KW - Railway vibration measurements KW - Vibration signal analysis KW - Wheel-rail tangential forces KW - Railway braking forces KW - Wheel-rail friction coefficient PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572309 DO - https://doi.org/10.3390/app13074132 VL - 13 IS - 7 SP - 1 EP - 15 PB - MDPI AN - OPUS4-57230 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -