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Anthropogenic sound in Florida's waters and coastal waterways is most commonly caused by overwater development, marine traffic, and military activity. Overwater construction has increased over the years as a result of aging infrastructure and rising expansions around the United States, including more than forty US Naval facilities containing tens of thousands of feet of pier. Construction methodology, such as pile driving, has risen in shallow waters to build structures such as bridges, piers, and wind farms, with significant consequences for marine life and the environment. More precisely, pile driving activities generate significant decibel levels in the surrounding marine environment. Measurements taken from hydrophones placed in the water near the construction site indicate that the high sound pressure levels produced may be harmful to marine life and the environment. As a result, standards have been established to help alleviate and decrease the possible harm that high decibel sound levels may produce. However, these additional steps increase the overall cost of the construction project. This thesis focuses on replicating the pile driving process using finite element modeling to hydroacoustic parametric study of pile driving-induced anthropogenic sound in neighboring Florida seas, as well as the possible environmental impact of the state's numerous naval base piers. The modeling predictions can then be used to identify the distance from the pile at which marine life and the environment are no longer adversely affected. In addition, computer modeling can reduce construction costs when compared to on-site sensors and monitoring. / Master of Science / Over recent years there has been an increase in the amount of manmade noise in Florida and its coastal waterways due to overwater construction, marine traffic, and military activities. Pile driving construction has increased in shallow waters to build infrastructure, which includes bridges, piers, and wind farms, resulting in a negative impact for marine life and the environment. Federal agencies have established guidelines to ease the harmful effects construction has on marine life and the environment. However, there is concern that these recent guidelines may not properly consider all the geometric and hydrographic variables of manmade noise that affect the high sound exposure levels during pile driving. With a more accurate understanding of the sound generation produced from pile driving, predictions can assist with sound mitigation to ensure less harm to the marine life and environment. In turn, construction companies and government agencies informed with this enhanced understanding can make better decisions that lead to fewer (or possibly eliminate) transmission loss discrepancies and costly noise mitigation measures. Consideration of the marine environment is one of the United States Navy's top priorities with naval stations located throughout the State of Florida that possess thousands of feet of waterfront structures, including piers, requiring routine maintenance and construction. This thesis models the pile driving process through finite element modeling in COMSOL Multiphysics computer software, testing the various parameters that Florida waters may encounter with pile driving on the surrounding coast as well as naval bases.

In order to fully understand the functionality of conformal devices, it is critical to develop computational models built from engineered models of 3-dimensional objects. This thesis established a scanning procedure to engineering 3D digital model for whole organs, known as template engineering. The resultant scanning data enabled designing, manufacturing, and modeling of novel organ healthcare devices. Specifically, we applied template engineering and structured-light scanning techniques to capture the 3D topographical information for whole organ systems. Sequentially, we developed multiphysics models for understanding the device functionality, including the function of devices for microfluidic interface and whole organ mechanical stabilization. / Master of Science / This study facilitated the development of computational models for whole organ healthcare devices. In order to develop a fundamental understanding of conforming biomedical devices for kidney assessment computational models were developed that simulate the interaction between the device and the soft organ. In this work, we generated a digital reconstruction of a porcine kidney model by surface scanning techniques that served as the domain two types of organ-devices interaction simulations: 1) organ-fluid contact problems and 2) organ-solid contact problems. This study proved that multiphysics modeling offers the potential toward the design and modeling of next-generation biomedical devices for whole organ healthcare.

L’objectif de ce travail est d'étudier expérimentalement la formation du capillaire durant le perçage et le soudage par faisceau laser, et de développer une simulation numérique permettant de reproduire la dynamique de formation et d'évolution du capillaire. Nous avons fait le choix d’utiliser comme matériau test le Zinc, en raison de ses propriétés thermodynamiques. Afin de simplifier le problème, nous avons étudié dans un premier temps le mécanisme de perçage. Deux méthodes expérimentales ont été utilisées pour caractériser l'évolution de la géométrie du capillaire : La méthode DODO (Direct Observation of Drilled hOle ) permet de visualiser le capillaire après perçage pour différentes durées et la méthode Zn-Quartz permet d’observer directement son évolution temporelle par camera rapide à travers une lame de quartz. Puis nous avons utilisé cette évolution pour mettre au point une simulation du mécanisme de perçage. Après avoir étudié le dépôt de puissance à l’intérieur d’un capillaire en tenant compte des réflexions multiples et estimé l'importance de la perte d'énergie et de matière lors du processus, nous avons développé une simulation en utilisant le logiciel Comsol Multiphysics couplant l'équation thermique, l'équation de Navier Stokes et prenant en compte le déplacement du métal fondu sous l’action de la pression de recul. Dans ce cas, on observe la formation d’un bourrelet important au bord du trou et une augmentation de la profondeur du capillaire. Ensuite nous avons étudié la formation du capillaire durant le soudage laser, c'est-à-dire avec déplacement de la source. A partir des techniques mises en œuvre pour l’étude du perçage nous avons obtenu l’évolution de la forme du capillaire dans le cas du soudage Zn/Quartz. Nous avons réalisé une simulation relativement simple en supposant la géométrie et la température du capillaire connues a priori. Nous avons constaté qu’un modèle simple, modélisant uniquement les transferts thermiques par conduction, permet de bien simuler la forme de la zone fondue pour les couples Zn/Zn et Zn-quartz. / The aim of the present work is to study experimentally the formation of the capillary during the drilling and welding by laser beam and to develop the numerical simulation which allows following the dynamics and the evolution of the keyhole. The zinc was chosen as a test material because its thermodynamical properties are well known. To simplify the problem, in the first place the drilling mechanism was studied. Two experimental methods were used to characterize the evolution of the keyhole: the Direct Observation of Drilled Hole method, which allows the visualization of the keyhole after the application of laser pulses of different durations, and Zn-Quartz method, which allows the direct observation of keyhole evolution with CCD camera through the layer of quartz. Then, the information on keyhole evolution was used to develop the simulation of drilling mechanism. After studying the beam power deposition inside the capillary with taking in account the multiple photon reflections, and after estimation of the energy and matter loss during the process, we developed the simulation with FEM software COMSOL Multiphysics, which contains coupled heat transfer, fluid flow and free surface problem allowing considering the effect of recoil pressure on liquid phase ejection. We could observe the formation of an important bolster surrounding the keyhole and the increase of keyhole depth with time. Next, we studied the formation of the keyhole during the laser welding, in other words, during the displacement of the heat source. Using the same technique that was developed for laser drilling, we have obtained the information on keyhole evolution during zinc-quartz welding. We have created the simple simulation, where keyhole temperature and profile were considered as known a priori. We have stated that this model, which takes in account only conduction heat transfer problem, allows to reproduce well the shape of the melted zone both for zinc-zinc and zinc-quartz couples

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I dagens samhälle ligger stort fokus på att bygga miljövänliga och energieffektiva byggnader. För att möta de allt mer skärpta energikraven måste hela klimatskalet beaktas där köldbryggor utgör en betydande del. Examensarbetet går ut på att göra en sammanställning av linjära köldbryggor (ψ) för vanligt förekommande konstruktionsdetaljer där köldbryggor finns. Sammanställningen där olika isoleringsmaterial på fasadskiva och isolertjocklekar tabelleras, ska underlätta för framtida projektering. Två simuleringsprogram för beräkning av köldbryggor har jämförts och utvärderats med varandra. Utvärderingen har gjorts med avseende på vilket program som var mest lämpat för att lösa frågeställningen. De två simuleringsprogrammen som används vid detta arbete är HEAT2 och COMSOL Multiphysics. Arbetet har resulterat i en lathund som finns tillgänglig på ELU:s intranät. Lathunden innehåller U-värde och ψ-värde med illustrering av konstruktionsdetaljerna och i detta arbete redovisas tillvägagångssätt och utförandet. En utvärdering av det lämpligaste program för utförandet av uppgiften finns också redovisad. / Currently there is a lot of focus on environmentally friendly and energy efficient buildings in our society. To face the more toughen energy requirements, the entire climate shell of the building has to be considered there thermal bridges constitute a significant part. This bachelor dissertation intends to create a compilation for Ψ-values of common construction details where thermal bridges are to be found. The compilation with a chart that includes insulating material and insulation thickness shall simplify in future projecting. Furthermore, two simulating programs for calculations of thermal bridges have been compared with each other. The two simulation programs that have been used in this dissertation are HEAT2 and COMSOL Multiphysics. This dissertation has resulted in a quick reference guide which is available at ELU`s internal network. This quick reference guide includes U-values and Ψ-values with an illustration of every construction detail and the procedure and execution is reported in this dissertation. An evaluation of which of the two programs that has been used was more appropriate for this purpose is presented as well.

Heavy forestry machines have great immediate effect on soil properties. This increases the interest to develop approaches that help understanding better the interaction between the forest machines and the terrain and consequently develop the forwarders to be gentle to the environment. The most predominant indications of soil disturbances caused by harvesting are mainly rutting and soil compaction. It is critical to understand and evaluate these damages to be able to protect the remaining trees and improve their tree growth rate. Comprehending the bearing capacity of the soil and the interaction between tire and soil are the key issues to develop forest machines that preserve the terrain. The first step to accomplish this goal is to compare the rut depth theoretical data from empirical models with the rut depth data from a full scale field test, the models suitable to predict rut depth is descripted. Tree roots reinforce the forest floor and significantly increase the bearing capacity of the soil. The contribution from root layer to the soil bearing capacity depends on the number, diameter, orientation of the roots and their mechanical properties. To improve the root tensile strength model, a root bending and stretching laboratory test has been carry out and compared with FEM-based results. The existing Valmet 860. 3 Adams MBS model is finally used to study the suitability of the model to predict rut depth. A comparison between several existing methods to predict rut depth is also shown. / Tunga skogsmaskiner har stor omedelbar effekt på markens egenskaper. Detta ökar intresset för att utveckla strategier som underlättar förståelsen av samverkan mellan skogsmaskiner och terrängen och därmed utveckla framdrivning av dessa maskiner som är skonsam mot miljön. De dominerande indikationerna på markstörningar orsakade av hjulbaserade skogsmaskiner är främst spårbildning och jordkompaktering. Det är viktigt att förstå och utvärdera dessa skador för att kunna skydda de kvarvarande träden och förbättra deras tillväxt. Att förstå markens bärighet och samspelet mellan däck och mark är de viktigaste frågorna för att utveckla skogsmaskiner som skonar terrängen. Det första steget för att uppnå detta mål är att jämföra spårdjup vilka är framtagna med empiriska modeller med data för spårdjup från ett fullskaligt fälttest, där de modeller som lämpar sig för att förutsäga spårdjup är beskrivna. Trädrötter förstärker skogsmarken och ökar avsevärt jordens bärighet. Bidraget från rotlagret till jordens bärförmåga beror på antalet rötter, deras diameter samt rötternas orientering och deras mekaniska egenskaper. För att förbättra modellen för rötternas mekaniska egenskaper har rotböjning och rottöjning studerats i ett laboratorietest och vidare jämförts med FEM-baserade resultat. Den befintliga MBS modellen av skotaren Valmet 860.3 har slutligen används för att studera lämpligheten av modellen för att förutsäga spårdjup. En jämförelse mellan flera olika metoder för att förutsäga spårdjup visas också.

The construction of infrastructures such as dams requires for the foundations to lay on stable ground. One way to do so is to grout the rock fractures present in the bedrock using concrete, and this also ensures that lower amounts of groundwater reach the infrastructure itself. However, the continuous flow of groundwater carrying various dissolved chemical compounds, will trigger over time the deterioration of the concrete grout by dissolving the mineral phases resulting from the hydration process. This study aims at determining the variations in porosity and hydraulic conductivity induced by the dissolution of portlandite content present in the grout following the groundwater flow. Eight different cases have been simulated in COMSOL Multiphysics®, based on various combinations of fracture geometry (rough and smooth), hydraulic gradient, and inflowing groundwater composition. Each model has two main components, one for the flow simulation and one for the reactive transport. The modules implemented from COMSOL Multiphysics® are Darcy’s Law, Chemistry, and Transport of Diluted Species in Porous Media. The software PHREEQC has been used to determine the chemical species concentration for both the initial and boundary conditions. The results show that, at the end of a 100-day period, the mineral concentration decreases from 56.27% to 61.27% depending on the simulation considered. This leads to an increase in porosity ranging from 1.94% to 2.23%, while hydraulic conductivity displays a minimum growth of 6.42% and a maximum of 7.43%. The sensitivity analysis results reveal that the most influencing factor on the degradation is the hydraulic gradient, which is followed by the fracture geometry, while the inflowing groundwater composition impact is not as high as the previous ones. / Byggandet av infrastrukturer som dammar kräver att grunden läggs på stabil mark. Ett sätt att uppnå detta är att fylla sprickor i berggrunden med betong, vilket också säkerställer att mindre mängder grundvatten når infrastrukturen. Det kontinuerliga flödet av grundvatten, som bär med sig olika lösta kemikalier, kan dock med tiden leda till att betongen bryts ner genom att mineralfaserna som bildas vid hydratiseringsprocessen löses upp. Denna studie undersöker hur porositeten och den hydrauliska ledningsförmågan förändras när portlandit i betongfogar löses upp av grundvattenflödet. Åtta olika scenarier har simulerats i COMSOL Multiphysics® med olika kombinationer av sprickgeometri (grov och slät), hydraulisk gradient och inkommande grundvattensammansättning. Varje modell består av två huvuddelar: en för flödessimulering och en för reaktiv transport. Modulerna från COMSOL Multiphysics® som används är Darcys lag, kemi och transport av utspädda ämnen i porösa medier. Programvaran PHREEQC har använts för att fastställa koncentrationen av kemiska ämnen för både initiala och gränsvillkor. Resultaten visar att efter 100 dagar minskar mineralkoncentrationen med mellan 56,27% och 61,27%, beroende på simuleringen. Detta leder till en ökning av porositeten med 1,94% till 2,23%, medan den hydrauliska ledningsförmågan ökar med minst 6,42% och högst 7,43%. Känslighetsanalysen visar att den hydrauliska gradienten är den mest påverkande faktorn för nedbrytningen, följd av sprickgeometrin. Sammansättningen av det inkommande grundvattnet har inte lika stor påverkan.

ANSYS ® AIMTM verbindet die Simulation mechanischer, strömungsmechanischer, thermischer und elektrischer Eigenschaften in einer neuen, intuitiven Oberfläche und einem über alle physikalischen Disziplinen gleichen Arbeitsprozess. Auf diese Weise kann die volle Breite physikalischer Fragestellungen nun auch direkt in der Produktentwicklung durch Konstrukteure und Entwicklungsingenieure genutzt werden, um ein ganzheitliches Produktverständnis zu erzielen. Wie dieser Zugang zur Produktsimulation für jeden Ingenieur mit ANSYS ® AIMTM erreicht wird, stellt der Vortrag unter folgenden Themenüberschriften heraus: - Paradigmenwechsel in der Produktentwicklung - Integriert Funktionen: • Multiphysics Simulation • Variantenanalysen • Geometriemodellierung • Prozessautomatisierung - ANSYS® AIMTM live in der Anwendung Das Produkt ANSYS® AIMTM ist seit Anfang 2015 als kommerzielles Produkt verfügbar. In den Versionen für Forschung und Lehre wird den Zugang mit der nächsten Softwareversion ermöglicht. Daher wird die Vorgehensweise in der Live Vorführung auch vielen langjährigen ANSYS ® Anwendenden neue Eindrücke geben. Im letzten Jahr wurde von CADFEM auf der SAXSIM Tagung ein allgemeiner Einblick in Möglichkeiten der gekoppelten Simulation mit ANSYS Workbench gegeben. Mittlerweile sind viele der dort genannten Anwendungsbeispiele einfacher in ANSYS ® AIMTM lösbar.