Orientador: Antonio Batocchio / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia mecanica / Made available in DSpace on 2018-08-04T09:12:59Z (GMT). No. of bitstreams: 1 Georges_MarcosRicardoRosa_D.pdf: 14421475 bytes, checksum: 9b0d8a6e3f4ee6f70d22ca5d2e3ec27f (MD5) Previous issue date: 2005 / Resumo: O presente trabalho propõe uma metodologia para conduzir o analista de simulação à criação dos modelos conceituais que são utilizados na simulação de sistema em eventos discretos. A modelagem conceitual é considerada uma das etapas mais importantes e complexas de um projeto de simulação, pois se trata de uma atividade que depende, exclusivamente, da habilidade do analista. Esta metodologia é composta de etapas que são baseadas em princípios gerais sobre modelagem que foram propostos por diversos autores. Algumas considerações sobre a coleta de dados são feitas, incluindo a aquisição do conhecimento e técnicas estatísticas de amostragem a serem utilizadas. Ao final é apresentado um estudo de caso em que a metodologia foi aplicada com sucesso, ilustrando e tomando mais fácil o entendimento da metodologia proposta / Abstract: This work proposes a methodology to lead the simulation analyst during the conceptual models creation which is used in discrete-event system simulation. The conceptual modeling is considered the most important and complex step in a simulation project because this activity depends on the analyst ability exclusively. This methodology is composed by steps which are based on general modeling principIes proposed by many authors. Some considerations about data collection are presented, including knowledge acquisition and statistical sampling techniques. At the end, a case study is shown, making easier its understanding / Doutorado / Materiais e Processos de Fabricação / Doutor em Engenharia Mecânica

Le développement des énergies renouvelables et des liaisons HVDC conduit à une augmentation de la pénétration de l’électronique de puissance dans les réseaux de transport d’électricité. Comme les convertisseurs possèdent des propriétés physiques différentes de celles des alternateurs synchrones, une évolution des contrôles employés s’avère nécessaire. Au vu de la taille des ensembles à simuler, la validation de solutions innovantes doit être réalisée par des simulations numériques et il est nécessaire d’être vigilant sur les outils utilisés afin d’éviter des temps de calcul prohibitifs. Dans cette thèse, des outils et des méthodes pour l’analyse et la simulation de réseaux de transport 100 % électronique de puissance sont développés. Une partie importante des travaux est consacrée à la modélisation des convertisseurs, ce qui permet de réaliser des simulations numériques plus ou moins précises en fonction du cahier des charges de l’étude et d’appliquer ou de développer des méthodes d’analyse de stabilité. Un modèle simplifié du réseau Irlandais est utilisé comme réseau exemple de façon à valider les méthodes et outils développés dans le cadre de la thèse. / The development of renewable generation and HVDC links lead to an important increase of the penetration of power electronics in the transmission systems. As Power Electronics converters have completely different physical behavior than synchronous machines, an evolution in the way TSOs control transmission systems is needed. It is impossible to build a real size prototype of a transmission system. The validation of the solutions must be done using dynamic numerical simulations. Because of the size of the studied systems, we have to be careful with the simulation tools that we use, in order to reduce the computation time. In this PhD tools and methods for the analysis and simulation of large transmission systems using 100% power electronics are developed. An important part of the work looks at the models of the converters. Those models allow us to do numerical simulations and to apply and develop stability and performance analysis methods for the considered system. A simple model of the Irish network will be used as an example in order to assess the developed methods.

Das Ziel der Dissertationsschrift bestand in der Entwicklung von Modellen, die notwendig waren, um eine komplexe Gebäudesimulation durchführen zu können. Dabei wurde der Schwerpunkt auf die Eigenentwicklung gelegt, während andere Modelle nur erwähnt und kurz beschrieben bzw. deren notwendige Erweiterungen erläutert wurden. Die Arbeit unterteilt sich in die Hauptpunkte Gebäude, Anlage, Modellverifizierung und Beispielrechnungen. Als Simulationswerkzeug wurde das Programmsystem TRNSYS verwendet, in welches letztendlich alle vorgestellten Modelle implementiert werden konnten.

Für die effiziente Blechtafelbearbeitung mit hoher Prozesssicherheit und Teilequalität ist die positions- und winkelgenaue Ausrichtung der Rohblechtafeln vor dem Bearbeitungsprozess erforderlich. Dieser Beitrag untersucht vibrationsbasierte Ausrichtkonzepte mittels Mehrkörpersystem-Simulation. Die entwickelten Simulationsmodelle ermöglichen die Charakterisierung und den Vergleich der Konzepte hinsichtlich der Bewegungs- und Ausrichteigenschaften sowie der erforderlichen Antriebskraft. / Efficient, reliable, and qualitative sheet metal processing requires both positional and angular alignment of the raw metal sheets prior to the manufacturing process. This paper investigates different vibration-based alignment concepts using a multi-body system simulation. The simulation model is then used to characterize and compare, with respect to the motion and alignment properties as well as the required driving force, the diverse vibration-based alignment concepts.

Ziel dieser Arbeit ist es, eine simulationsbasierte Untersuchung des Betriebs eines PEM-Brennstoffzellensystems mit besonderem Fokus auf den Wasserhaushalt zu ermöglichen. In PEM-Brennstoffzellen sind die Wechselwirkungen in Bezug auf den Feuchtehaushalt z.B. von Transportmechanismen, Degradation und Leistung abhängig. Im PEM-Brennstoffzellensystem werden die Wechselwirkungen der Feuchte durch eine mögliche Rezirkulation und/oder eine passive Befeuchtung der Kathode erweitert, Um diese Abhängigkeiten korrekt darzustellen, wurde ein PEM-Brennstoffzellen Stack-Modell entwickelt, das einerseits einen hohen Grad an Detailtreue und andererseits hohe Anforderungen an die Laufzeit erfüllt, um akzeptable Simulationszeiten für Brennstoffzellensystemsimulationen zu ermöglichen. Der Kern des Modells ist eine neuartige 2-D + 1-D Struktur, die flächenspezifische Bedingungen, wie z.B. trockene Kathodeneinlass- und feuchte Kathodenauslassbedingungen in Abhängigkeit von Gleich- oder Gegenstromstrukturen, löst. Um diesen Anforderungen an die Laufzeit gerecht zu werden, wurde ein numerischer Löser entwickelt, der speziell an die Struktur und den Inhalt angepasst ist. Das Brennstoffzellenmodell und dessen Möglichkeiten zur Integration in eine Systemsimulation werden in dieser Arbeit vorgestellt. / The aim of this work is to enable simulation based investigation of the operation of a PEM fuel cell system, with the special focus on its water management. For PEM fuel cells their multi-level interaction regarding humidity is characteristic depending e.g. on transport mechanisms, degradation and performance. In the PEM fuel cell system, the interaction of the humidity is further enhanced by a possible recirculation and passive humidification systems of the cathode. In order to display these dependencies correctly, a PEM fuel cell stack model has been developed, which on the one hand meets high degree of resulting details and on the other hand meets high requirements concerning its runtime, to enable acceptable simulation times for fuel cell system simulations. The core of the model is a novel 2-D + 1-D structure that resolves area specific conditions, such as dry cathode inlet and wet cathode outlet conditions in dependence of co- or counter flow fields. To meet those requirements regarding its runtime a numerical solver has been developed that is specially adapted to the structure and content. The fuel cell model as well as its possibilities with respect to the integration in system simulation is presented in this work.

Die Stanzbiopsie ist ein etabliertes minimalinvasives Verfahren im Rahmen der interventionellen Diagnostik, bei der Proben menschlichen Gewebes für histologische Untersuchungen zur Erkennung bzw. zum Nachweis u. a. karzinogener Gewebe entnommen werden. Zur Gewebeentnahme wird ein zweiteilig aufgebautes Nadelsystem in das Zielgewebe eingeschossen. Bei der Beobachtung dieses Prozesses sind auffällige Nadelablenkungen des Systems erkennbar. Ursächlich dafür sind die an der Nadelspitze unsymmetrisch angreifenden Kräfte in Verbindung mit der geringen Biegesteifigkeit des Nadelsystems. Im Rahmen eines öffentlich geförderten Projektes konnten an realitätsnahen Gewebephantomen experimentelle Untersuchungen zur Quantifizierung der Nadelablenkungen durchgeführt sowie ein mathematischer Ansatz zur Simulation dieses Effekts entwickelt werden. Darauf aufbauend wurde ein neuer Nadelschliff entwickelt, der eine wesentliche Verbesserung des aktuellen Status bringt. / Biopsy is an established method of the minimally invasive medicine to take human tissue samples for examination determining the presence or extent of a disease. Frequently applied method to detect a prostate or breast cancer is the punch biopsy. The components of the used devices include an inner needle with a notch sampling the tissue and an outer cannula to cut the tissue. During the biopsy, the doctor inserts the needle system into the human tissue under supervision by sonography to support the needle steering. After pushing the trigger, the components of the needle system move successively and penetrate the desired area. The device consists of a two-part spring mechanism to generate the needle movement. Observations of the needle movement by a highspeed camera shows a considerable deflection of the needle tip which makes tapping and tissue sampling more difficult. This is caused by unbalanced forces acting on the needle tip and the low bending stiffness of the needle. Publicly financed experimental studies in the quantification of the needle deflection were undertaken and a mathematical approach for the simulation of these effects was developed. The model, which consists of a flexible needle and a parameterized tissue model, is implemented in the multibody simulation software Recurdyn.

Nowadays, PEM fuel cell systems for passenger cars are always realized as hybrid systems. If the architecture of a hybrid system is given, then the dimensioning of the fuel cell and battery subsystems is crucial in terms of costs, dynamics, and driving behavior in general. In order to analyze these dependencies correctly, the ZBT fuel cell model was integrated into a fuel cell system and a full vehicle simulation. The subject of the investigation is the interaction of different drive cycles, which in part are very different, with differently dimensioned sub models for the fuel cell system and the battery. The ZBT fuel cell model is integrated into the simulation environment AVL CRUISE™ M for the fuel cell system and the vehicle. An analysis is presented that compares the different drive cycles and system dimensions and provides specific recommendations for different use cases.

Classical Continuous System Simulation (CSS) is restricted to modelling continuous flows, and therefore, cannot correctly realise a conceptual model with discrete objects. The development of Full Potential CSS solves this problem by (1) handling discrete quantities as discrete and continuous matter as continuous, (2) preserving the sojourn time distribution of a stage, (3) implementing attributes correctly, and (4) describing different types of uncertainties in a proper way. In order to apply Full Potential CSS a new software, StochSD, has been developed. This thesis evaluates StochSD's ability to model Full Potential CSS, where the points 1-4 above are included. As a test model a well-defined conceptual epidemic model, which includes all aspects of Full Potential CSS, was chosen. The study was performed by starting with a classical SIR model and then stepwise add the different aspects of the Conceptual Model. The effects of each step were demonstrated in terms of size and duration of the epidemic. Finally, the conceptual model was also realised as an Agent Based Model (ABM). The results from 10 000 replications each of the CSS and ABM models were compared and no statistical differences could be confirmed. The conclusion is that StochSD passed the evaluation.

La conception de systèmes embarqués devient de plus en plus complexe. Ces systèmes sont hétérogènes dans le sens où ils nécessitent l’intégration de composants décrits au moyen de plusieurs disciplines scientifiques, par exemple, l’électricité, l’optique, la thermique, la mécanique, la chimie ou la biologie. De plus, ces disciplines peuvent être représentées dans des domaines temporels différents, par exemple, le domaine des événements discrets, celui du temps discret, ou celui du temps continu. Face à cette situation, les concepteurs ont besoin d’outils de modélisation et de simulation efficaces pour décrire le comportement d’un système hétérogène dans un environnement de simulation unique. Nous examinons la possibilité de modéliser, de simuler et de synchroniser les systèmes multi-disciplines dans le même environnement, en utilisant comme référence la norme de simulation « SystemC Analog/Mixed-Signal (AMS) ». Nous analysons la méthode introduite par SystemC AMS pour synchroniser le domaine des événements discrets avec celui du temps discret, et nous identifions ses inconvénients. Nous proposons une formalisation du problème de synchronisation qui permet de détecter les problèmes existants dans un modèle avant la simulation. Nous proposons un prototype de simulateur appelé « SystemC Multi-Disciplinary Virtual Prototyping (MDVP) », qui est implémenté comme une extension de SystemC. Il permet la modélisation, l’élaboration, et la simulation hiérarchique de systèmes multi-disciplines au moyen de plusieurs modèles de calcul. Pour concevoir le simulateur MDVP, nous introduisons un nouveau principe de synchronisation entre plusieurs modèles de calcul. En outre, nous introduisons une méthodologie pour ajouter, dans le prototype de simulateur, des modèles de calcul représentés par plusieurs domaines temporels. Nous appliquons cette méthodologie pour ajouter un modèle de calcul « Timed Data Flow (TDF) » dans SystemC MDVP. Ce modèle de calcul repose sur la sémantique du temps discret introduite par SystemC AMS, et sur la formalisation du principe de synchronisation entre le domaine des événements discrets et celui du temps discret. Nous mettons en œuvre le modèle de calcul TDF, dans le cas d’un capteur de vibrations et son circuit numérique. Ce modèle comporte une boucle d’asservissement et plusieurs interactions entre le domaine des événements discrets et celui du temps discret. / The design of embedded systems is currently an increasingly complex problem. These systems tend to become heterogeneous in the sense that they require the integration of components described by means of different physical/engineering disciplines, for example, electrical, optical, thermal, mechanical, chemical, or biological. Besides, these disciplines can be described under different time domains, for example, Discrete Event (DE), Discrete Time (DT), or Continuous Time (CT). To address this problem, designers require modeling and simulation tools to describe the system’s components under different time domains and synchronize them in the same simulation environment. We explore the possibilities of modeling, simulating and synchronizing multi-disciplinary systems in the same environment, using as reference the SystemC Analog/Mixed-Signal (AMS) simulation standard. We analyze the method introduced in SystemC AMS for synchronizing the DE and DT domains, and we identify its drawbacks. Besides, we introduce a new formalization of the synchronization problem, which is used to detect issues in a model before simulation. We propose a simulator prototype called SystemC Multi-Disciplinary Virtual Prototyping (MDVP), which is implemented as an extension of SystemC. It allows the modeling, and the generic hierarchical elaboration and simulation of multi-disciplinary systems, by means of different Models of Computation (MoCs). To build the MDVP simulator, we introduce a synchronization principle to handle interactions between MoCs. In addition, we introduce a methodology to add, in the simulator prototype, MoCs described under different time domains. We apply this methodology to add a Timed Data Flow MoC in SystemC MDVP. This MoC implements the DT semantics introduced by the SystemC AMS standard, and is based on the synchronization principle between the DE and DT domains. Using the TDF MoC, we implement and simulate a case study of a vibration sensor model and its digital front end circuit. This case study includes a feedback loop and several interactions between the DE and DT domains.

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