TY - CHAP A1 - Martins-Wagner, Magda A1 - Wagner, Marcus A1 - Haufe, André A1 - Liebold, Christian T1 - A Graphical User Interface for Simulating Resin-Transfer-Molding Combining LS-DYNA and OpenFOAM T2 - 10th European LS-DYNA Conference 2015, Würzburg, Germany N2 - The paper describes parts of the joint research project Swim-RTM including several industrial and academic partners. Its goal is to combine LS-DYNA and the open-source CFD solver OpenFOAM to simulate the production process of continuous fiber-reinforced plastics, particularly the resin-transfer-molding (RTM) process, in which the layers of dry fabric (unidirectional or woven) are formed in the mold (draping) and then filled with liquid resin with high pressure at injection points. Through a combined analysis of both the structural mechanical and the fluid dynamical phases, a better prediction and thereby optimization of the textile components properties as well as injection points can be achieved, improving the manufacturing process. The draping simulation of the fabric layers is carried out with LS-DYNA, while the injection simulation of the matrix material is performed in full 3D with OpenFOAM. A key question in this research project is how local porosities can be derived from the structural computation in the draping step. The purpose of the presented subproject is to develop a graphical user interface (GUI) to enable the simulation of the entire RTM process of long-fiber-reinforced components including the transfer of results between the draping and injection phases. The complete simulation task is relatively complex and involves several software packages, meaning a high effort for the user to get familiarized with. To circumvent this, the GUI aims at requiring from the user only the minimum necessary input data, creating and running the simulation and mapping tasks in the background, and showing graphically all demanded intermediate and final results. For the draping step several current fabric materials such as *MAT_034, *MAT_234, *MAT_235, *MAT_249 are available. Several modelling techniques for the composite setup are also conceivable, including a workflow similar to metal forming applications. In the injection step the fabric is modelled as a porous medium and different transport models and liquid resin types are at hand. For the data transfer between the draping and injection models, i.e. the mapping of data between shell and volume meshes within the developed GUI, first the OpenFOAM volume mesh is converted to LS-DYNA format and the necessary passing parameters are extracted from the output files, then the mapping tool DYNAmap [3] from DYNAmore GmbH is invoked, and finally the OpenFOAM command files are created. After the injection simulation is started and successfully terminated, information, such as the distribution of air inclusions or the shear stress distribution to analyze the reorientation of component fibers, is available and can be transferred from the 3D fluid mesh to an LS-DYNA shell mesh for further computations, for instance a crash simulation. This backward data mapping between volume and shell meshes can then be performed inside the GUI. Y1 - 2015 UR - https://www.researchgate.net/publication/280836408_A_Graphical_User_Interface_for_Simulating_Resin-Transfer-Molding_Combining_LS-DYNA_and_OpenFOAM ER - TY - JOUR A1 - Broser, Christian A1 - Falter, Thomas A1 - Ławrowski, Robert Damian A1 - Altenbuchner, Amelie A1 - Vögele, Daniel A1 - Koss, Claus A1 - Schlamp, Matthias A1 - Dunnweber, Jan A1 - Steffens, Oliver A1 - Heckner, Markus A1 - Jaritz, Sabine A1 - Schiegl, Thomas A1 - Corsten, Sabine A1 - Lauer, Norina A1 - Guertler, Katherine A1 - Koenig, Eric A1 - Haug, Sonja A1 - Huber, Dominik A1 - Birkenmaier, Clemens A1 - Krenkel, Lars A1 - Wagner, Thomas A1 - Justus, Xenia A1 - Saßmannshausen, Sean Patrick A1 - Kleine, Nadine A1 - Weber, Karsten A1 - Braun, Carina N. A1 - Giacoppo, Giuliano A1 - Heinrich, Michael A1 - Just, Tobias A1 - Schreck, Thomas A1 - Schnabl, Andreas A1 - Gilmore, Amador Téran A1 - Roeslin, Samuel A1 - Schmid, Sandra A1 - Wellnitz, Felix A1 - Malz, Sebastian A1 - Maurial, Andreas A1 - Hauser, Florian A1 - Mottok, Jürgen A1 - Klettke, Meike A1 - Scherzinger, Stefanie A1 - Störl, Uta A1 - Heckner, Markus A1 - Bazo, Alexander A1 - Wolff, Christian A1 - Kopper, Andreas A1 - Westner, Markus A1 - Pongratz, Christian A1 - Ehrlich, Ingo A1 - Briem, Ulrich A1 - Hederer, Sebastian A1 - Wagner, Marcus A1 - Schillinger, Moritz A1 - Görlach, Julien A1 - Hierl, Stefan A1 - Siegl, Marco A1 - Langer, Christoph A1 - Hausladen, Matthias A1 - Schreiner, Rupert A1 - Haslbeck, Matthias A1 - Kreuzer, Reinhard A1 - Brückl, Oliver A1 - Dawoud, Belal A1 - Rabl, Hans-Peter A1 - Gamisch, Bernd A1 - Schmidt, Ottfried A1 - Heberl, Michael A1 - Gänsbauer, Bianca A1 - Bick, Werner A1 - Ellermeier, Andreas A1 - Monkman, Gareth J. A1 - Prem, Nina A1 - Sindersberger, Dirk A1 - Tschurtschenthaler, Karl A1 - Aurbach, Maximilian A1 - Dendorfer, Sebastian A1 - Betz, Michael A. A1 - Szecsey, Tamara A1 - Mauerer, Wolfgang A1 - Murr, Florian ED - Baier, Wolfgang T1 - Forschung 2018 T3 - Forschungsberichte der OTH Regensburg - 2018 KW - Forschung KW - Forschungsbericht Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-13826 SN - 978-3-9818209-5-9 CY - Regensburg ER - TY - CHAP A1 - Hollweck, Christoph A1 - Leidinger, Lukas A1 - Hartmann, Stefan A1 - Li, Liping A1 - Wagner, Marcus A1 - Wüchner, Roland T1 - Systematic assessment of isogeometric sheet metal forming simulations based on trimmed, multi-patch NURBS models in LS-DYNA T2 - 14th European LS-DYNA Conference, October 18 and 19, 2023, Baden-Baden, Germany N2 - Isogeometric sheet metal forming simulation is a numerical simulation technique that is used to predict the behavior of sheet metal parts during the forming process [1] and tries to tighten the link with the Computer Aided Design (CAD) description. This technique uses the isogeometric analysis (IGA) approach, which combines the well-established framework of traditional finite element analysis (FEA) and the power of non-uniform rational B-splines (NURBS). In contrast to the approach in a “classical” FEA framework, IGA directly uses the ansatzspace of the CAD geometry for analysis, which opens the possibility to work directly on the exact geometry. Furthermore, the smoothness of the NURBS basis functions results in a more accurate simulation [2]. A powerful method to reduce the computational effort is adaptive mesh refinement, that has been developed and optimized for sheet metal forming applications over several years for standard Finite Elements. However, it remains an open question how an efficient local adaptive mesh refinement strategy can be implemented for complex industrial sheet metal forming simulations based on trimmed NURBS models, which are typically the description in Boundary Representation (B-Rep) CAD-models [3]. First investigations for explicit dynamics have been made in [4]. In this contribution, a detailed comparison between FEA and IGA sheet metal forming applications is conducted. The state of the art for FEA and IGA will be contrasted and the need for an efficient adaptive mesh refinement strategy will be discussed. The goal of our research is to develop an efficient adaptive mesh refinement strategy for isogeometric sheet metal forming simulations in LS-DYNA. This will contribute to closing the efficiency gap between IGA and FEA in explicit dynamics, accelerate the product development process and enable the application of IGA in industrial sheet metal forming simulations. Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-68228 PB - DYNAmore ER - TY - CHAP A1 - Wiesent, Lisa A1 - Geith, Markus A. A1 - Wagner, Marcus T1 - Simulation of Fluid-Structure Interaction between injection medium and balloon catheter using ICFD T2 - 11th European LS-DYNA Conference 2017, 9 - 11 May, Salzburg, Austria N2 - Arteriosclerosis is a major health issue worldwide. While it is commonly treated by the implantation of an balloon-expandable stent, micro injuries may occur during stent deployment, and induce in-stent restenosis, whose consequence can be fatal. Studying this undesirable phenomenon is usually limited as experimental data is hard to obtain on ethical ground. Numerical simulation are performed to better understand this problem. To construct a more realistic simulation of a balloon-expandable stent, a partitioned strongly-coupled FSI simulation of the balloon deployment was set up using the ICFD solver of LS-DYNA, - a quite innovative approach. The complex balloon configuration as well as the interaction of the injection medium and the balloon structure was considered. The balloon structure consisting of shell elements was obtained from preliminary balloon folding and pleating simulations. The balloon consists of a flexible thin walled polyamide. The injection fluid is implemented using volume elements. Balloon deployment was initiated by a pressure boundary condition inducing a volume flow into the balloon. The initial feasibility analysis showed promising result including a continuous balloon deployment and a reasonable development of the fluid pressure and velocity field. However, applying this FSI approach to a more complex balloon structure led to a non convergent solution. The non-convergence could be mainly reduced to mechanical factors including the low wall thickness of the balloon (< 0.05 mm) and the flexibility of the polyamide. Further, the ICFD solver shows less accuracy concerning the FSI conditions when dealing with thin flexible structures as well as enclosed volumes. A shell thickness of 0.06 mm is believed to result in a convergent solution. KW - Koronare Herzkrankheit KW - Stent KW - Ballondilatation KW - Numerische Strömungssimulation Y1 - 2017 UR - https://www.dynalook.com/conferences/11th-european-ls-dyna-conference/icfd-solver-and-fsi/simulation-of-fluid-structure-interaction-between-injection-medium-and-balloon-catheter-using-icfd SN - 978-3981621549 ER - TY - JOUR A1 - Geith, Markus A. A1 - Swidergal, Krzysztof A1 - Hochholdinger, Bernd A1 - Schratzenstaller, Thomas A1 - Wagner, Marcus A1 - Holzapfel, Gerhard A. T1 - On the importance of modeling balloon folding, pleating, and stent crimping: An FE study comparing experimental inflation tests JF - International Journal for Numerical Methods in Biomedical Engineering N2 - Finite element (FE)–based studies of preoperative processes such as folding,pleating, and stent crimping with a comparison with experimental inflation tests are not yet available. Therefore, a novel workflow is presented in which residual stresses of balloon folding and pleating, as well as stent crimping, and the geometries of all contact partners were ultimately implemented in an FE code to simulate stent expansion by using an implicit solver. The numerical results demonstrate that the incorporation of residual stresses and strains experienced during the production step significantly increased the accuracy of the subsequent simulations, especially of the stent expansion model. During the preoperative processes, stresses inside the membrane and the stent material also reached a rather high level. Hence, there can be no presumption that balloon catheters or stents are undamaged before the actual surgery. The implementation of the realistic geometry, in particular the balloon tapers, and the blades of the process devices improved the simulation of the expansion mech-anisms, such as dogboning, concave bending, or overexpansion of stent cells. This study shows that implicit solvers are able to precisely simulate the mentioned preoperative processes and the stent expansion procedure without a preceding manipulation of the simulation time or physical mass. KW - Catheter KW - Coronary KW - Crimping KW - Finite element KW - Stent KW - Stent KW - Implantation KW - Simulation KW - Finite-Elemente-Methode Y1 - 2019 U6 - https://doi.org/10.1002/cnm.3249 N1 - This study was funded by the Bavarian Research Foundation within the project “PIZ‐225‐18” VL - 35 IS - 11 PB - Wiley ER - TY - GEN A1 - Geith, Markus A. A1 - Swidergal, Krzysztof A1 - Schratzenstaller, Thomas A1 - Holzapfel, Gerhard A. A1 - Wagner, Marcus T1 - Numerical analysis of stent delivery systems during pre- and intraoperative processes T2 - 15. Deutsches LS-DYNA Forum, 15.-17.10.2018, Bamberg Y1 - 2018 UR - https://www.researchgate.net/publication/335260823_Numerical_analysis_of_stent_delivery_systems_during_pre-_and_intraoperative_processes ER - TY - CHAP A1 - Schmailzl, Anton A1 - Amann, Thomas A1 - Glockner, Markus A1 - Fandanelli, Martin A1 - Wagner, Marcus A1 - Hierl, Stefan ED - CADFEM GmbH, ED - ANSYS Germany GmbH, T1 - Finite element analysis of thermoplastic probes under tensile load using ls-dyna compared to ansys workbench 14 in correlation to experimental investigations T2 - ANSYS Conference & 30th CADFEM Users' Meeting - ACUM, 24.-26- Oktober 2012, Kassel N2 - Joining thermoplastic requisitions is a popular technique to build sophisticated plastic applications. Therefore the laser-transmission welding process is used to join thermoplastic polymers in visible regions. The clamping force in this case plays a decisive role when it comes to the weld quality. Simulating the clamping pressure with finite element techniques is therefore highly attractive to understand the principal of the process. Thermoplastic polymers under tensile load often show a brittle behavior coupled with softening. Simulating such materials is quite difficult for FEM programs. In this case a finite element study of the tensile test in LS-DYNA and ANSYS Wb 14 with respect to the material models was analysed. The experimental data get validated in comparison with the FEM solution for a tensile test. The material models and the problems in simulating softening behavior for thermoplastic polymers were discussed Y1 - 2012 UR - https://www.oth-regensburg.de/fileadmin/media/fakultaeten/m/labore/FEM/pdf/fb-2012_paper_acum.pdf N1 - DVD-ROM SP - 1 EP - 10 CY - Grafing bei München ER - TY - JOUR A1 - Wagner, Marcus A1 - Pinsky, Peter M. A1 - Malhotra, Manish T1 - A multiple-frequency partial-field method for exterior acoustics based on Padé via lanczos approximants JF - Proceedings of the ASME Noise Control and Acoustics Division - 2001 : presented at the 2001 ASME International Mechanical Engineering Congress and Exposition, November 11 - 16, 2001, New York, New York N2 - A solution methodology is introduced for the efficient computation of the acoustic field over restricted domains and for a frequency window. Typically, such partial field solutions include, for example, surfaces enclosing the radiating structure or even single points in the computational domain. The multiple-frequency partial-field (MFPF) method starts out by reformulating the finite element matrix system into a suitable shifted form. The DtN map is used as a radiation boundary condition and is interpreted as a low rank update of the matrix problem. The shifted standard form is then approximated by a rational matrix-valued Padé approximant and solved simultaneously over a frequency range. To obtain the Padé approximation, a banded unsymmetric Lanczos process is applied on the standard shifted form exploiting the matrix Padé-via-Lanczos connection. Numerical examples show the feasibility of the outlined procedure. Y1 - 2001 SN - 0-7918-3551-0 U6 - https://doi.org/10.1115/IMECE2001/NCA-23524 IS - 28 SP - 229 EP - 234 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Ottawa, Patrycja A1 - Romano, Marco A1 - Ehrlich, Ingo A1 - Wagner, Marcus A1 - Gebbeken, Norbert T1 - The influence of ondulation in fabric reinforced composites on dynamic properties in a mesoscopic scale T2 - 11. LS-DYNA Forum, 9. - 10. Oktober 2012, Ulm N2 - Structural mechanic properties of fiber reinforced plastics depend on the single components’ properties, namely matrix and fiber [5]. Simple micromechanic homogenization theories reach a limit when a laminate consists of fabric reinforced layers instead of unidirectional layers. The ondulations of warp and fill yarn caused by the textile semi-finished product are the reason why the mesoscopic scale, which is in between the microscopic and the macroscopic scale, has to be taken into account when mechanically characterizing fabric reinforced composites [3]. In this scale a mesomechanic kinematic can be derived analytically. Especially, when considering free damped vibrations of structures the repeated acting of the kinematic correlation significantly affects the damping behaviour to higher values compared to theoretically predicted damping ratios. The model is investigated using Finite-Element-Analyses and basically validated experimentally. Y1 - 2012 UR - https://www.dynamore.de/de/download/papers/dynamore/de/download/papers/ls-dyna-forum-2012/documents/materials-5-2 SP - 171 EP - 172 ER - TY - RPRT A1 - Hederer, Sebastian A1 - Wagner, Marcus ED - Baier, Wolfgang T1 - Entwicklung und Implementierung eines konstitutiven Modells zur Beschreibung der Plastizität von Dualphasenstähle bei großen plastischen Deformationen T2 - Forschungsbericht 2018 / Ostbayerische Technische Hochschule Regensburg Y1 - 2018 UR - https://doi.org/10.35096/othr/pub-1382 SN - 9783981820911 SP - 68 EP - 69 ER - TY - RPRT A1 - Thumann, Philipp A1 - Swidergal, Krzysztof A1 - Wagner, Marcus ED - Baier, Wolfgang T1 - Experimentelle Ermittlung von Materialkennwerten und numerische Untersuchungen an einem gefüllten Elastomer T2 - Forschungsbericht 2015 / Ostbayerische Technische Hochschule Regensburg Y1 - 2015 UR - https://doi.org/10.35096/othr/pub-1386 SN - 978-3-00-048589-3 SP - 49 EP - 50 ER - TY - CHAP A1 - Koch, F. A1 - Thumann, Philipp A1 - Wagner, Marcus T1 - Simulation with implicit time integration of high loaded areas of a forming tool for large presses using LS-DYNA T2 - 13. LS-DYNA Forum 2014, 6.-8. Oktober, Bamberg Y1 - 2016 ER - TY - CHAP A1 - Thumann, Philipp A1 - Swidergal, Krzysztof A1 - Wagner, Marcus T1 - Calculation and validation of material tests with specimens made out of filled elastomers T2 - 10th European LS-DYNA Conference 2015, Würzburg N2 - In deep-drawing dies for steel sheet parts of car bodies huge masses are moved. To prevent vibrations, which occur by sudden acceleration or stopping of those masses, elastomeric tubular dampers [1] are used. The dampers are made out of carbon filled elastomers. A good knowledge about the material behaviour of metals is available. But for the numerical investigation of complete deep-drawing dies the elastomeric dampers must be taken into account, too. To characterize the material behaviour of the elastomers tensile tests and pressure tests were carried out. The received material data from the tests were read into LS-DYNA [2]. Simulation models of the tensile test and the pressure test were created for LS-DYNA according to the real dimensions and boundary conditions. For validation purposes, calculations of loading cycles were done to enable a comparison between test data and simulation results. For the calculations the implemented material model *MAT_SIMPLIFIED_RUBBER_WITH_DAMAGE (*MAT_183) was used. The comparison shows a good fitting between the test data and the calculation results with respect to the mechanical material behaviour by using this material model in single loading cases. The settings from the simulations of material tests were transferred to simulations of dampers, which are used in deep-drawing dies. Y1 - 2015 UR - https://www.semanticscholar.org/paper/Calculation-and-validation-of-material-tests-with-Thumann-Swidergal/7502f1c70a07654c8238f4a6bd436aa5bd4c051f ER - TY - JOUR A1 - Ledentsov, Dmitry A1 - Düster, Alexander A1 - Volk, Wolfram A1 - Wagner, Marcus A1 - Heinle, Ingo A1 - Rank, Ernst T1 - Model adaptivity for industrial application of sheet metal forming simulation JF - Finite Elements in Analysis and Design N2 - finite element simulation of sheet metal forming, shell elements are widely used. The limits of applicability of the shell elements are sometimes disregarded, which leads to an error in predictions of important values such as springback geometry. The underlying kinematic assumptions of the shell elements do not hold where the thickness of In the metal sheet approaches the value of the radius of curvature. Complex three-dimensional material behavior effects cannot be represented precisely as the result of the simplified kinematics. Here we present a model adaptivity scheme based on a model error indicator. The model-adaptive technique presented in this paper aides to resolve only the critical areas of the structure with a three-dimensional discretization while keeping reasonable computational cost by utilizing shell elements for the rest of the structure. The model error indicator serves as a guide for subsequent automatic adaptive re-meshing of the work-piece followed by a model-adaptive finite element analysis. The accuracy of the approximation obtained by the model-adaptive technique coincides well with that of a more expensive solution obtained with solid elements only. KW - Finite elements KW - Model adaptivity KW - Coupled analysis KW - Model error KW - Sheet metal forming Y1 - 2010 U6 - https://doi.org/10.1016/j.finel.2010.02.006 VL - 46 IS - 7 SP - 585 EP - 600 ER - TY - CHAP A1 - Wegh, Niels A1 - Wagner, Marcus A1 - Gaudlitz, Daniel A1 - Finckh, Hermann A1 - Klein, Markus T1 - Numerical Simulation of Filling Process in Resin Transfer Molding T2 - 13th International Conference on Flow Processes in Composites Materials (FPCM-13), Kyoto, Japan Y1 - 2016 UR - https://www.fose1.plymouth.ac.uk/sme/fpcm/fpcm13/Abstracts/FPCM-13_extended_abstract_21.pdf ER - TY - CHAP A1 - Meckl, D. A1 - Lubeseder, Christian A1 - Zausinger, C. A1 - Wurmb, Ingo von A1 - Meinhardt, Josef A1 - Swidergal, Krzysztof A1 - Wagner, Marcus T1 - Simulation of press dies for large presses using the flexible multibody dynamics in Recurdyn T2 - 4th RecurDyn TechnologyDays 2014, München Y1 - 2014 ER - TY - CHAP A1 - Geith, Markus A. A1 - Wagner, Marcus T1 - Numerical Analysis Of Stent Delivery Systems During Pre- And Intraoperative Processes T2 - Deutsches LS-DYNA Forum 2018, Bamberg Y1 - 2018 ER - TY - CHAP A1 - Thumann, Philipp A1 - Schmauser, Philipp A1 - Buchner, Stefan A1 - Wagner, Marcus T1 - Festigkeitsbewertung von hochbeanspruchten Kupferkomponenten T2 - Tagung Auslegung von Bauteilen aus Kupfer und Kupferlegierungen, 14. und 15. Mai 2025, Goslar N2 - Es wird gezeigt, wie durch ein ganzheitliches Konzept, beginnend mit der Modellerstellung eines umfangreichen FE-Berechnungsmodells bis hin zur Festigkeitsbewertung unter Verwendung speziell ermittelter Werkstoffkenndaten, die Betriebssicherheit von hochbeanspruchten Kupferkomponenten sichergestellt werden kann. Mit den durchgeführten Werkstoffversuchsreihen an wärmebehandelten und weichgeglühten Kupferproben aus Cu-ETP R250 wurden neben den Standard-Werkstoffkenndaten wie Streckgrenze Rp, Zugfestigkeit Rm, Bruchdehnung A und Elastizitätsmodul E Parameter zur Beschreibung des Werkstoffverhaltens bei zyklischer Belastung bestimmt. Zusätzlich wurde wurde in Abhängigkeit der Wärmebehandlung und der damit verbundenen Ver- oder Entfestigung die Schwingfestigkeit eruiert. Somit ist mit der vorgestellten methodischen Vorgehensweise unter Verwendung tatsächlicher Werkstoffsteifigkeiten und umfangreicher Schwingfestigkeitsdaten eine Betriebsfestigkeitsbewertung möglich. KW - zyklischer Werkstoffversuch KW - Kupfer KW - Schwingfestigkeit Y1 - 2025 U6 - https://doi.org/10.48447/Cu-2025-569 PB - Deutscher Verband für Materialforschung und -prüfung e.V. ER - TY - BOOK A1 - Wagner, Marcus T1 - Lineare und nichtlineare FEM BT - Eine Einführung mit Anwendungen in der Umformsimulation mit LS-DYNA® N2 - Einführung in die lineare FEM - Mechanische Größen der Strukturmechanik - Mathematische Modellierung über Energieprinzipien - Diskretisierung mit Finiten Elementen - Finite-Elemente-Klassen - Mathematische und numerische Aspekte der FEM - Geometrische Nichtlinearität - Materielle Nichtlinearität - Kontaktmodellierung - Gleichungslösung bei nichtlinearen statischen Problemen - Zeitintegration von nichtlinearen dynamischen Problemen - Blechumformsimulation - Anhang: Mathematische Hilfsmittel - Einführung in die Simulation mit LS-DYNA® Die Zielgruppen- Studierende aus Bachelor- und Masterstudiengängen der Ingenieurwissenschaften an Hochschulen und Technischen Universitäten - Ingenieure und Techniker KW - Blechumformen KW - Finite-Elemente-Methode KW - Nichtlineare Finite-Elemente-Methode KW - Strukturmechanik Y1 - 2022 SN - 978-3-658-36521-9 U6 - https://doi.org/10.1007/978-3-658-36522-6 VL - 2022 PB - Springer Fachmedien; Springer Vieweg CY - Wiesbaden ET - 3.,überarbeitete und erweiterte Auflage ER - TY - CHAP A1 - Schneider, Sebastian A1 - Mühlbauer, Christian A1 - Sittl, Christopher A1 - Rottengruber, Hermann A1 - Rabl, Hans-Peter A1 - Wagner, Marcus A1 - Verhey, Jesko L. ED - Rottengruber, Hermann ED - Luft, Tommy ED - Schneider, Sebastian T1 - Tickergeräuschanalyse an einem Otto-DI-Motor mittels empirischer Bewertungsformel T2 - Motor- und Aggregate-Akustik: 11. Magdeburger Symposium, Tagungsband N2 - Beim Kauf eines Pkw wird der akustische Qualitätseindruck eines Fahrzeugantriebstrangs stetig relevanter. Die wahrgenommene Geräuschqualität des Motoraggregates nimmt hierbei eine Schlüsselrolle ein. Aufgrund der Ausprägung einzelner Störgeräusche wird jene Geräuschqualität negativ beeinflusst. Diese als unangenehm empfundenen Geräuschkomponenten gilt es im Rahmen der Fahrzeugentwicklung weiter zu reduzieren, wobei die Identifikation und Bewertung störender Geräuschanteile am Motorgesamtgeräusch Voraussetzungen für eine effektive Akustikoptimierung sind. Vor allem das impulshafte Tickergeräusch wird bei Otto-DI-Motoren als besonders lästig eingestuft, weswegen dieser Beitrag darauf abzielt, die tickernden Geräuschanteile aus dem Gesamtgeräusch zu analysieren und zu bewerten. Hierzu wurde eine empirische Formel entwickelt, welche die tickernden Geräuschanteile in ihrer Intensität in Grenzen einstufen kann. Diese ist rein empfindungsbasiert und besteht aus der Impulshaftigkeit, der Lautheit sowie der Schärfe des Motorgesamtgeräusches. Wie auch bei anderen psychoakustischen Bewertungsskalen wurde die Benotung von 1 (sehr tickernd) bis 10 (nicht tickernd) vorgenommen. Anhand von Hörversuchen mithilfe einer Expertenjury konnte die Tickergeräuschbewertungsformel anschließend verifiziert werden. Hiernach kann präzise ausgesagt werden, in welchen Motorkennfeldbereichen das Tickergeräusch die Angenehmheit des Motorgesamtgeräusches untergräbt. KW - Messtechnik KW - Geräuschentwicklung KW - Psychoakustik KW - Schallentstehung Y1 - 2021 SN - 978-3-948749-02-6 U6 - https://doi.org/10.25673/36611 SP - 65 EP - 86 PB - Otto-von-Guericke-Universität CY - Magdeburg ER - TY - BOOK A1 - Wagner, Marcus T1 - Lineare und nichtlineare FEM BT - Eine Einführung mit Anwendungen in der Umformsimulation mit LS-DYNA® N2 - Dieses Lehrbuch bringt im ersten Teil leicht verständlich die Merkmale und Eigenschaften linearer finiter Elemente aus dem Bereich der Elastostatik und Dynamik und erläutert Vorgehensweisen bei der Erstellung von Simulationsmodellen. Im zweiten Teil liegt der Schwerpunkt auf nichtlinearen zeitabhängigen Vorgängen und Lösungsverfahren. Praxisbeispiele aus der Umformtechnik werden anschaulich mit der Software LS-DYNA® gelöst. Der Fokus liegt auf einer Erklärung der Zusammenhänge, die für Anwender kommerzieller Software notwendig sind. Theoretische Grundlagen werden in dem Umfang dargestellt, der für das Verständnis der Benutzung eines Programms notwendig ist. Y1 - 2017 SN - 978-3-658-17865-9 U6 - https://doi.org/10.1007/978-3-658-17866-6 PB - Springer CY - Wiesbaden ER - TY - BOOK A1 - Wagner, Marcus T1 - Lineare und nichtlineare FEM N2 - Einführung in die lineare FEM - Mechanische Größen der Strukturmechanik - Mathematische Modellierung über Energieprinzipien - Diskretisierung mit Finiten Elementen - Finite-Elemente-Klassen - Mathematische und numerische Aspekte der FEM - Geometrische Nichtlinearität - Materielle Nichtlinearität - Kontaktmodellierung - Gleichungslösung bei nichtlinearen statischen Problemen - Zeitintegration von nichtlinearen dynamischen Problemen - Blechumformsimulation - Anhang: Mathematische Hilfsmittel - Einführung in die Simulation mit LS-DYNA® Die Zielgruppen- Studierende aus Bachelor- und Masterstudiengängen der Ingenieurwissenschaften an Hochschulen und Technischen Universitäten - Ingenieure und Techniker KW - Blechumformen KW - Finite-Elemente-Methode KW - LS-DYNA KW - Nichtlineare Finite-Elemente-Methode KW - Strukturmechanik Y1 - 2019 SN - 978-3-658-25051-5 U6 - https://doi.org/10.1007/978-3-658-25052-2 PB - Springer Fachmedien; Springer Vieweg CY - Wiesbaden ET - 2. Auflagae ER -