{"id":{"repo_id":"tu-berlin","oai_identifier":"oai:depositonce.tu-berlin.de:11303/23467"},"canonical_url":"https://search.dev.ndltd.org/etd/tu-berlin/oai:depositonce.tu-berlin.de:11303/23467","repository":{"repo_id":"tu-berlin","name":"Technische Universität Berlin","base_url":"https://api-depositonce.tu-berlin.de/server/oai/request"},"display":{"title":"Implementation of a comprehensive methodology for structural dynamics and NVH simulation incorporating MBS, FEM and ray tracing","abstract":"To meet the fundamental requirements of environmental preservation, mitigating noise pollution stemming from railroad vehicles is imperative. Manufacturers and operators of rolling stock exhibit a keen interest in simulation tools tailored for calculating acoustic emissions from rails and vehicles. These tools not only furnish robust assistance and actionable insights for the early-stage development of resilient rails and vehicles but also offer cost-effective alternatives to prototype development and experimental endeavors. However, the paramount prerequisite for such a tool encompasses not only rapid computation but also the utmost accuracy achievable. Comprehensive acoustic simulation entails a highly intricate process, necessitating explicit simulation of Multi-Body Simulations (MBSs) alongside Finite Element Methods (FEMs) with millions of Degrees of Freedom (DOF). Such computations place substantial demands on computer performance. However, owing to significant advancements in computer capabilities, these once-complex models can now be readily computed on personal computers. This advancement in computational power offers an excellent assurance for numerical simulations of acoustics. In this thesis, a foundational model for calculating rolling noise is established. Initially, a comprehensive spatial vehicle-rail coupling model is developed to compute wheel-rail contact forces utilizing Timoshenko and Euler-Bernoulli beam theories, Multi-Body Dynamics (MBDs), and Hertzian nonlinear wheel-rail contact theory. This model not only corrects for the conformal contact of the wheel-rail to prevent discontinuities in contact points resulting from numerical calculations but also accounts for the influence of wheel and rail flexibility on the wheel-rail forces. Using this model, wheel-rail contact forces and Track Decay Rates (TDRs) are computed and validated through field experiments and in SIMPACK. The track parameters are predicted using an Artificial Neural Network (ANN). Subsequently, Equivalent Radiated Power Level (ERPL) of the wheel and rail under a unit force of 1N (also known as Noise Transfer Function (NTF)) as well as Panel Contribution Analysis (PCA) of the components are calculated in FEM models, providing the foundation for targeted acoustic optimization of the wheel and rail. Finally, a model of sound propagation outside the vehicle is constructed based on ray tracing theory. In this model, each wheel is treated as a blend of monopole and dipole sources, while each rail is regarded as a line source comprised of multiple monopole sources. The Sound Pressure Level (SPL) and the distribution of SPL on a reception plane, located at a distance of 7.5m, are computed. An analysis of the PCA of the rails revealed high sound radiation at the rail feet. Subsequently, the efficacy of reinforcing the UIC60 rail at this location in reducing radiated noise was explored. The results demonstrate a potential reduction in rail noise by 2.7 dB through this strategy. Additionally, the impact of rail pad stiffness and damping, as well as rail dampers, on rolling noise, was investigated. The results indicate that increasing rail pad damping can effectively compensate for the negative impact on acoustics resulting from the low stiffness of the rail pad. Moreover, employing suitable rail dampers proves to be an effective measure in reducing rolling noise. According to the calculations in this thesis, it is inferred that these two measures can reduce the noise generated by the 49E1 rail by 5.5 dB and 5.6 dB, respectively.","abstract_html":"To meet the fundamental requirements of environmental preservation, mitigating noise pollution stemming from railroad vehicles is imperative. Manufacturers and operators of rolling stock exhibit a keen interest in simulation tools tailored for calculating acoustic emissions from rails and vehicles. These tools not only furnish robust assistance and actionable insights for the early-stage development of resilient rails and vehicles but also offer cost-effective alternatives to prototype development and experimental endeavors. However, the paramount prerequisite for such a tool encompasses not only rapid computation but also the utmost accuracy achievable. Comprehensive acoustic simulation entails a highly intricate process, necessitating explicit simulation of Multi-Body Simulations (MBSs) alongside Finite Element Methods (FEMs) with millions of Degrees of Freedom (DOF). Such computations place substantial demands on computer performance. However, owing to significant advancements in computer capabilities, these once-complex models can now be readily computed on personal computers. This advancement in computational power offers an excellent assurance for numerical simulations of acoustics. In this thesis, a foundational model for calculating rolling noise is established. Initially, a comprehensive spatial vehicle-rail coupling model is developed to compute wheel-rail contact forces utilizing Timoshenko and Euler-Bernoulli beam theories, Multi-Body Dynamics (MBDs), and Hertzian nonlinear wheel-rail contact theory. This model not only corrects for the conformal contact of the wheel-rail to prevent discontinuities in contact points resulting from numerical calculations but also accounts for the influence of wheel and rail flexibility on the wheel-rail forces. Using this model, wheel-rail contact forces and Track Decay Rates (TDRs) are computed and validated through field experiments and in SIMPACK. The track parameters are predicted using an Artificial Neural Network (ANN). Subsequently, Equivalent Radiated Power Level (ERPL) of the wheel and rail under a unit force of 1N (also known as Noise Transfer Function (NTF)) as well as Panel Contribution Analysis (PCA) of the components are calculated in FEM models, providing the foundation for targeted acoustic optimization of the wheel and rail. Finally, a model of sound propagation outside the vehicle is constructed based on ray tracing theory. In this model, each wheel is treated as a blend of monopole and dipole sources, while each rail is regarded as a line source comprised of multiple monopole sources. The Sound Pressure Level (SPL) and the distribution of SPL on a reception plane, located at a distance of 7.5m, are computed. An analysis of the PCA of the rails revealed high sound radiation at the rail feet. Subsequently, the efficacy of reinforcing the UIC60 rail at this location in reducing radiated noise was explored. The results demonstrate a potential reduction in rail noise by 2.7 dB through this strategy. Additionally, the impact of rail pad stiffness and damping, as well as rail dampers, on rolling noise, was investigated. The results indicate that increasing rail pad damping can effectively compensate for the negative impact on acoustics resulting from the low stiffness of the rail pad. Moreover, employing suitable rail dampers proves to be an effective measure in reducing rolling noise. According to the calculations in this thesis, it is inferred that these two measures can reduce the noise generated by the 49E1 rail by 5.5 dB and 5.6 dB, respectively.","abstract_has_math":false,"creators":["Tian, Qiuyong"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Hecht, Markus"],"committee_chairs":[],"committee_members":[],"year":2024,"date_issued":"2024","date_published":"2024","updated_at":"2026-07-27T21:28:37Z","subjects":[],"languages":["en"],"rights":[],"rights_urls":["https://creativecommons.org/licenses/by/4.0/"],"identifier_entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://doi.org/10.14279/depositonce-22281"],"render_values":[{"text":"https://doi.org/10.14279/depositonce-22281","href":"https://doi.org/10.14279/depositonce-22281","code":true}]}]},"links":{"outbound_url":"https://depositonce.tu-berlin.de/handle/11303/23467","outbound_label":"Repository record","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Hecht, Markus"]},{"key":"dc:creator","label":"Author","values":["Tian, Qiuyong"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2024-12-10T14:12:17Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2024-12-10T14:12:17Z"]},{"key":"dc:date.issued","label":"Date","values":["2024"]},{"key":"dc:type","label":"Dc Type","values":["Doctoral Thesis"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"key":"dc:rights.uri","label":"Rights URI","values":["https://creativecommons.org/licenses/by/4.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://depositonce.tu-berlin.de/handle/11303/23467","https://doi.org/10.14279/depositonce-22281"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["To meet the fundamental requirements of environmental preservation, mitigating noise pollution stemming from railroad vehicles is imperative. Manufacturers and operators of rolling stock exhibit a keen interest in simulation tools tailored for calculating acoustic emissions from rails and vehicles. These tools not only furnish robust assistance and actionable insights for the early-stage development of resilient rails and vehicles but also offer cost-effective alternatives to prototype development and experimental endeavors. However, the paramount prerequisite for such a tool encompasses not only rapid computation but also the utmost accuracy achievable. Comprehensive acoustic simulation entails a highly intricate process, necessitating explicit simulation of Multi-Body Simulations (MBSs) alongside Finite Element Methods (FEMs) with millions of Degrees of Freedom (DOF). Such computations place substantial demands on computer performance. However, owing to significant advancements in computer capabilities, these once-complex models can now be readily computed on personal computers. This advancement in computational power offers an excellent assurance for numerical simulations of acoustics. In this thesis, a foundational model for calculating rolling noise is established. Initially, a comprehensive spatial vehicle-rail coupling model is developed to compute wheel-rail contact forces utilizing Timoshenko and Euler-Bernoulli beam theories, Multi-Body Dynamics (MBDs), and Hertzian nonlinear wheel-rail contact theory. This model not only corrects for the conformal contact of the wheel-rail to prevent discontinuities in contact points resulting from numerical calculations but also accounts for the influence of wheel and rail flexibility on the wheel-rail forces. Using this model, wheel-rail contact forces and Track Decay Rates (TDRs) are computed and validated through field experiments and in SIMPACK. The track parameters are predicted using an Artificial Neural Network (ANN). Subsequently, Equivalent Radiated Power Level (ERPL) of the wheel and rail under a unit force of 1N (also known as Noise Transfer Function (NTF)) as well as Panel Contribution Analysis (PCA) of the components are calculated in FEM models, providing the foundation for targeted acoustic optimization of the wheel and rail. Finally, a model of sound propagation outside the vehicle is constructed based on ray tracing theory. In this model, each wheel is treated as a blend of monopole and dipole sources, while each rail is regarded as a line source comprised of multiple monopole sources. The Sound Pressure Level (SPL) and the distribution of SPL on a reception plane, located at a distance of 7.5m, are computed. An analysis of the PCA of the rails revealed high sound radiation at the rail feet. Subsequently, the efficacy of reinforcing the UIC60 rail at this location in reducing radiated noise was explored. The results demonstrate a potential reduction in rail noise by 2.7 dB through this strategy. Additionally, the impact of rail pad stiffness and damping, as well as rail dampers, on rolling noise, was investigated. The results indicate that increasing rail pad damping can effectively compensate for the negative impact on acoustics resulting from the low stiffness of the rail pad. Moreover, employing suitable rail dampers proves to be an effective measure in reducing rolling noise. According to the calculations in this thesis, it is inferred that these two measures can reduce the noise generated by the 49E1 rail by 5.5 dB and 5.6 dB, respectively.","Um die grundlegenden Umweltschutzanforderungen zu erfüllen, ist es erforderlich, die Lärmbelastung von Schienenfahrzeugen zu begrenzen. Hersteller und Betreiber von Schienenfahrzeugen zeigen großes Interesse an Simulationstools zur Berechnung der Schallemissionen von Schiene und Fahrzeugen. Diese Tools bieten nicht nur eine effektive Unterstützung und Anleitung für die Entwicklung leiserer Schienen und Fahrzeuge in einer frühen Entwicklungsphase, sondern sind auch kostengünstiger im Vergleich zur Entwicklung von Prototypen und durchgeführten Experimenten. Die Hauptanforderung an ein solches Werkzeug ist jedoch nicht nur eine schnelle Berechnung, sondern auch höchstmögliche Genauigkeit. Die umfassende akustische Simulation ist ein äußerst komplexer Prozess, der nicht nur die explizite Simulation der Mehrkörperdynamik, sondern auch die implizite Finite-Elemente-Simulation mit Millionen von Freiheitsgraden erfordert, was hohe Anforderungen an die Rechenleistung des Computers stellt. Dank erheblicher Verbesserungen der Computerleistung können diese ehemals komplexen Modelle heute problemlos auf Personalcomputer berechnet werden. Dies ermöglicht eine zuverlässige numerische Simulation der Akustik. Diese Arbeit konzentriert sich auf die Entwicklung eines Basismodells zur Berechnung des Rollgeräuschs von Schienenfahrzeugen. Zunächst wird ein vollständiges räumliches Fahrzeug-Gleisgekoppeltes Modell entworfen, das auf der Timoshenko- und Euler-Bernoulli-Balkentheorie, der Mehrkörperdynamik und der nichtlinearen Hertzschen Rad-Schiene-Kontakttheorie basiert. In diesem Modell wird nicht nur der konforme Kontakt zwischen Rad und Schiene korrigiert, um durch numerische Berechnungen verursachte Sprünge in den Rad-Schiene-Kontaktpunkten zu vermeiden, sondern es wird auch der Einfluss der Flexibilität von Rad und Schiene auf die Rad-Schiene-Kräfte berücksichtigt. Mithilfe dieses Modells werden die Rad-Schiene-Kontaktkräfte und die Gleisabklingrate berechnet und durch Experimente sowie in SIMPACK validiert. Zudem werden die Gleisparameter mithilfe eines künstlichen neuronalen Netzwerks abgeschätzt. Im zweiten Schritt werden im Finite-Elemente-Modell die äquivalente Strahlungsleistung des Rades und der Schiene unter Anregung in Höhe von 1N sowie die akustische Beiträge der Fläche jedes Bauteils berechnet, um eine gezielte Optimierung von Rad und Schiene zu ermöglichen. Im letzten Schritt wird ein Modell der Schallausbreitung außerhalb des Fahrzeugs nach dem Prinzip der Raytracing-Theorie entwickelt, wobei jedes Rad als eine Mischung aus Monopol- und Bipolquellen und jede Schiene als eine Linienquelle betrachtet wird. Dabei werden der Schalldruckpegel und die Verteilung des Schalldruckpegels in einem Abstand von 7.5m berechnet. Die Analyse des Oberflächenbeitrags der Schienen ergibt, dass die Schallabstrahlung an dem Schienenfuß signifikant ist. Daher wird die Auswirkung einer Verstärkung des UIC60-Schienenprofils an dieser Stelle auf den abgestrahlten Lärm untersucht. Die Ergebnisse deuten darauf hin, dass diese Maßnahme eine Reduzierung des Lärms um 2.7 dB bewirken kann. Des Weiteren werden die Auswirkungen der Steifigkeit und Dämpfung der Zwischenlage sowie des Schienenstegdämpfers auf das Rollgeräusch untersucht. Die Ergebnisse zeigen, dass eine Erhöhung der Dämpfung der Zwischenlage die negativen Auswirkungen auf die Akustik, die durch die geringe Steifigkeit der Zwischenlage verursacht werden, effektiv kompensieren kann. Ein geeigneter Schienenstegdämpfer ist ebenfalls eine wirksame Maßnahme zur Reduzierung des Rollgeräuschs. Basierend auf den Berechnungsergebnissen dieser Arbeit lässt sich schließen, dass diese beiden Maßnahmen den von der 49E1-Schiene erzeugten Lärm um 5.5 dB bzw. 5.6 dB reduzieren können."]},{"key":"dc:title","label":"Title","values":["Implementation of a comprehensive methodology for structural dynamics and NVH simulation incorporating MBS, FEM and ray tracing"]}]}],"canonical_facts":{"dc:contributor.advisor":["Hecht, Markus"],"dc:creator":["Tian, Qiuyong"],"dc:date.accessioned":["2024-12-10T14:12:17Z"],"dc:date.available":["2024-12-10T14:12:17Z"],"dc:date.issued":["2024"],"dc:description.abstract":["To meet the fundamental requirements of environmental preservation, mitigating noise pollution stemming from railroad vehicles is imperative. Manufacturers and operators of rolling stock exhibit a keen interest in simulation tools tailored for calculating acoustic emissions from rails and vehicles. These tools not only furnish robust assistance and actionable insights for the early-stage development of resilient rails and vehicles but also offer cost-effective alternatives to prototype development and experimental endeavors. However, the paramount prerequisite for such a tool encompasses not only rapid computation but also the utmost accuracy achievable. Comprehensive acoustic simulation entails a highly intricate process, necessitating explicit simulation of Multi-Body Simulations (MBSs) alongside Finite Element Methods (FEMs) with millions of Degrees of Freedom (DOF). Such computations place substantial demands on computer performance. However, owing to significant advancements in computer capabilities, these once-complex models can now be readily computed on personal computers. This advancement in computational power offers an excellent assurance for numerical simulations of acoustics. In this thesis, a foundational model for calculating rolling noise is established. Initially, a comprehensive spatial vehicle-rail coupling model is developed to compute wheel-rail contact forces utilizing Timoshenko and Euler-Bernoulli beam theories, Multi-Body Dynamics (MBDs), and Hertzian nonlinear wheel-rail contact theory. This model not only corrects for the conformal contact of the wheel-rail to prevent discontinuities in contact points resulting from numerical calculations but also accounts for the influence of wheel and rail flexibility on the wheel-rail forces. Using this model, wheel-rail contact forces and Track Decay Rates (TDRs) are computed and validated through field experiments and in SIMPACK. The track parameters are predicted using an Artificial Neural Network (ANN). Subsequently, Equivalent Radiated Power Level (ERPL) of the wheel and rail under a unit force of 1N (also known as Noise Transfer Function (NTF)) as well as Panel Contribution Analysis (PCA) of the components are calculated in FEM models, providing the foundation for targeted acoustic optimization of the wheel and rail. Finally, a model of sound propagation outside the vehicle is constructed based on ray tracing theory. In this model, each wheel is treated as a blend of monopole and dipole sources, while each rail is regarded as a line source comprised of multiple monopole sources. The Sound Pressure Level (SPL) and the distribution of SPL on a reception plane, located at a distance of 7.5m, are computed. An analysis of the PCA of the rails revealed high sound radiation at the rail feet. Subsequently, the efficacy of reinforcing the UIC60 rail at this location in reducing radiated noise was explored. The results demonstrate a potential reduction in rail noise by 2.7 dB through this strategy. Additionally, the impact of rail pad stiffness and damping, as well as rail dampers, on rolling noise, was investigated. The results indicate that increasing rail pad damping can effectively compensate for the negative impact on acoustics resulting from the low stiffness of the rail pad. Moreover, employing suitable rail dampers proves to be an effective measure in reducing rolling noise. According to the calculations in this thesis, it is inferred that these two measures can reduce the noise generated by the 49E1 rail by 5.5 dB and 5.6 dB, respectively.","Um die grundlegenden Umweltschutzanforderungen zu erfüllen, ist es erforderlich, die Lärmbelastung von Schienenfahrzeugen zu begrenzen. Hersteller und Betreiber von Schienenfahrzeugen zeigen großes Interesse an Simulationstools zur Berechnung der Schallemissionen von Schiene und Fahrzeugen. Diese Tools bieten nicht nur eine effektive Unterstützung und Anleitung für die Entwicklung leiserer Schienen und Fahrzeuge in einer frühen Entwicklungsphase, sondern sind auch kostengünstiger im Vergleich zur Entwicklung von Prototypen und durchgeführten Experimenten. Die Hauptanforderung an ein solches Werkzeug ist jedoch nicht nur eine schnelle Berechnung, sondern auch höchstmögliche Genauigkeit. Die umfassende akustische Simulation ist ein äußerst komplexer Prozess, der nicht nur die explizite Simulation der Mehrkörperdynamik, sondern auch die implizite Finite-Elemente-Simulation mit Millionen von Freiheitsgraden erfordert, was hohe Anforderungen an die Rechenleistung des Computers stellt. Dank erheblicher Verbesserungen der Computerleistung können diese ehemals komplexen Modelle heute problemlos auf Personalcomputer berechnet werden. Dies ermöglicht eine zuverlässige numerische Simulation der Akustik. Diese Arbeit konzentriert sich auf die Entwicklung eines Basismodells zur Berechnung des Rollgeräuschs von Schienenfahrzeugen. Zunächst wird ein vollständiges räumliches Fahrzeug-Gleisgekoppeltes Modell entworfen, das auf der Timoshenko- und Euler-Bernoulli-Balkentheorie, der Mehrkörperdynamik und der nichtlinearen Hertzschen Rad-Schiene-Kontakttheorie basiert. In diesem Modell wird nicht nur der konforme Kontakt zwischen Rad und Schiene korrigiert, um durch numerische Berechnungen verursachte Sprünge in den Rad-Schiene-Kontaktpunkten zu vermeiden, sondern es wird auch der Einfluss der Flexibilität von Rad und Schiene auf die Rad-Schiene-Kräfte berücksichtigt. Mithilfe dieses Modells werden die Rad-Schiene-Kontaktkräfte und die Gleisabklingrate berechnet und durch Experimente sowie in SIMPACK validiert. Zudem werden die Gleisparameter mithilfe eines künstlichen neuronalen Netzwerks abgeschätzt. Im zweiten Schritt werden im Finite-Elemente-Modell die äquivalente Strahlungsleistung des Rades und der Schiene unter Anregung in Höhe von 1N sowie die akustische Beiträge der Fläche jedes Bauteils berechnet, um eine gezielte Optimierung von Rad und Schiene zu ermöglichen. Im letzten Schritt wird ein Modell der Schallausbreitung außerhalb des Fahrzeugs nach dem Prinzip der Raytracing-Theorie entwickelt, wobei jedes Rad als eine Mischung aus Monopol- und Bipolquellen und jede Schiene als eine Linienquelle betrachtet wird. Dabei werden der Schalldruckpegel und die Verteilung des Schalldruckpegels in einem Abstand von 7.5m berechnet. Die Analyse des Oberflächenbeitrags der Schienen ergibt, dass die Schallabstrahlung an dem Schienenfuß signifikant ist. Daher wird die Auswirkung einer Verstärkung des UIC60-Schienenprofils an dieser Stelle auf den abgestrahlten Lärm untersucht. Die Ergebnisse deuten darauf hin, dass diese Maßnahme eine Reduzierung des Lärms um 2.7 dB bewirken kann. Des Weiteren werden die Auswirkungen der Steifigkeit und Dämpfung der Zwischenlage sowie des Schienenstegdämpfers auf das Rollgeräusch untersucht. Die Ergebnisse zeigen, dass eine Erhöhung der Dämpfung der Zwischenlage die negativen Auswirkungen auf die Akustik, die durch die geringe Steifigkeit der Zwischenlage verursacht werden, effektiv kompensieren kann. Ein geeigneter Schienenstegdämpfer ist ebenfalls eine wirksame Maßnahme zur Reduzierung des Rollgeräuschs. Basierend auf den Berechnungsergebnissen dieser Arbeit lässt sich schließen, dass diese beiden Maßnahmen den von der 49E1-Schiene erzeugten Lärm um 5.5 dB bzw. 5.6 dB reduzieren können."],"dc:identifier.uri":["https://depositonce.tu-berlin.de/handle/11303/23467","https://doi.org/10.14279/depositonce-22281"],"dc:language.iso":["en"],"dc:rights.uri":["https://creativecommons.org/licenses/by/4.0/"],"dc:title":["Implementation of a comprehensive methodology for structural dynamics and NVH simulation incorporating MBS, FEM and ray tracing"],"dc:type":["Doctoral Thesis"]},"updated_at":"2026-07-27T21:28:37Z"}