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Ion Permeation through Membrane Channels: Molecular Dynamics Simulations StudiesMustafa, Morad 10 July 2008 (has links) (PDF)
Molecular dynamics simulation was used to study ion permeation through different membrane proteins embedded in a lipid bilayer (DMPC) with different saline solutions. The potential of mean force (PMF) for ion transport was obtained by umbrella sampling simulations. A revised MacKerell force field for tryptophan residues was studied using gramicidin A (gA) channel as a test model. The revised force field contribution to the Na+ PMF was consonant with the prediction from the experimental results, but in stark contrast to the prediction of the CHARMM force field, version 22, for the tryptophan side-chain. A new grid-based correction map algorithm by MacKerell group, called CMAP, was introduced into the CHARMM force field, version 31. The CMAP algorithm focused on optimizing phi, psi dihedral parameters for the peptide backbone. The CMAP corrections reduced the excessive translocation barrier. Decomposition demonstrated the reduction in the translocation barrier was due to effects on the K+ PMFH2O rather than on K+ PMFgA. The presence of negatively charged sulfonate group at the entrance and exit of the gA channel affected the depth and the location of the highly occupied sites. The negatively charged sulfonate group produced a strong attraction for the cations in the bulk towards the channel mouth. In the M2 transmembrane domain channel (M2-TMD), three M2-TMD structures were studied, differing only in whether the selectivity-filter (four His37 side-chains) was uncharged, +2 charged, or +3 charged. M2-TMD structural properties were compared with the structural properties of other models extracted from NMR and X-ray studies. The spontaneous cation and anion entry into the charged selectivity-filter was different from that into a neutral selectivity-filter. Cl- ions had a lower free-energy barrier in the selectivity-filter than either Na+ or NH4+ ions through the M2-TMD channel. NH4+ ions had a lower free-energy barrier in the selectivity-filter than Na+ ions. Based on accessible rotamer conformations, a revised conductance mechanism was proposed. In this conductance mechanism, the His37 side-chain functioned as an acceptor and donor group, whereas the Trp41 side-chain functioned as a carrying group.
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MULTIBODY APPROACH FOR RAILWAY DYNAMIC ANALYSISElsayed Abdel Hameed Amer Shaltout, Ramy 14 March 2013 (has links)
En este trabajo se ha llevado a cabo el desarrollo de una herramienta computacional para la simulación dinámica de vehículos ferroviarios. El modelo está basado en técnicas multicuerpo debidas a Shabana. Con respecto a otras metodologías existentes, la propuesta hace uso de un conjunto de sistemas de referencia que permite el empleo de coordenadas independientes sin la posibilidad de configuraciones singulares debidas a grandes giros. El conjunto de sistemas de referencia sirve de base para formular de manera precisa el problema de contacto rueda-carril. El programa está diseñado para considerar de forma flexible distintas configuraciones de vehículo así como diversas geometrías de trazado. La estructura del programa está abierta a cambios orientados a la mejora del modelo de contacto rueda-carril o a la implementación de la dinámica estructural de la vía. Se ha implementado un modelo eficiente que permite detectar con precisión las coordenadas de los puntos en contacto localizados en la interfase entre la rueda y el carril. La herramienta de simulación desarrollada en esta tesis se ha aplicado para diferentes casos-estudio con el objetivo de validar la idoneidad de la metodología propuesta en el análisis del sistema ferroviario. Se ha realizado una comparación entre los resultados obtenidos por la herramienta de simulación presentada y los resultados ofrecidos por varios programas comerciales de simulación dinámica en el análisis del vehículo de Manchester Benchmark. Además, la herramienta se ha empleado para desarrollar un análisis dinámico del vehículo de la locomotora TGV y los resultados obtenidos se han comparado con los ofrecidos por el programa comercial SIMPACK para el mismos modelo de vehículo, bajo las mismas condiciones de operación. Finalmente, sobre la base de la calidad de los resultados, se puede concluir que la herramienta de simulación es fiable y eficiente para emplearse en el análisis dinámico de los diferentes sistemas ferroviarios. / Elsayed Abdel Hameed Amer Shaltout, R. (2013). MULTIBODY APPROACH FOR RAILWAY DYNAMIC ANALYSIS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/27622
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Parametric CAD Modeling to aid Simulation-Driven Design : An evaluation and improvement of methods used at ScaniaGrandicki, Andreas, Lokgård, Mattias January 2017 (has links)
This report documents a thesis conducted at Scania CV AB in Södertälje, Sweden. The main purpose of the thesis has been to examine and improve upon current practices of parametric CAD-modeling at Scania, with the ultimate goal of increased design automation and simulation-driven design. The thesis was initiated with a literature study, mainly covering the fields of parametric CAD-modeling, design automation and knowledge-based engineering. Furthermore, a questionnaire and multiple interviews were conducted to assess the awareness and mind-set of the employees. Finally, a case-study was carried out to follow current methodologies, and address any deficiencies found. Some of the most important findings were that while parametric modeling has considerable potential in enabling design automation, it is crucial, and most beneficial in terms of automation efficiency, to start with the fundamentals, namely achieving a uniform modeling practice. With these findings, a new proposed methodology has been introduced, as well as a recommended plan for a widespread implementation of parametric modeling at Scania. Such implementation would allow for shorter lead-times, faster adaptation to changing conditions, and reduced development expenditures.
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Estudo da inferência de carregamento em histórias de vôos simulados na liga de Al aeronáutico SAE-AMS 7475 T7351 / Loading study of inference in a simulated flights history using an SAE-AMS 7475 T7351 aluminum alloy.Ruchert, Cassius Olivio Figueiredo Terra 28 March 2007 (has links)
Este trabalho discutiu o estudo da inferência de carregamento e a reconstrução fratográfica da taxa de propagação da trinca por fadiga em histórias de vôos simulados do tipo Twist, mini-Twist, Falstaff e mini-Falstaff. O material estudado foi uma liga de alumínio de grau aeronáutico SAE-AMS 7475 T7351 na qual foram obtidas as propriedades mecânicas a partir dos ensaios de tração e dureza, análise química, metalográfica. Foram realizados ensaios de amplitude constante de carregamento em corpos de prova com geometria tipo C(T) extraídos de um bloco e ensaios de amplitude variável em corpos de prova com geometria tipo M(T) extraídos de uma placa. Corpos de prova do tipo C(T) foram extraídos da orientação L-T e T-L, à temperatura ambiente com diferentes espessuras para a realização de ensaios de propagação de trinca por fadiga (da/dN vs. ΔK) com distintos valores de razão de carregamento,R (0,1;0,3; 0,5; 0,7 e 0,8) de acordo com a norma ASTM-E647 (1993). Foram realizados dois tipos de ensaios de fadiga com amplitude constante de carregamento. Primeiro, o ensaio com ΔP constante para obtenção dos dados dos estágios II e III das curvas da/dN vs. ΔK para distintos valores de R e, posteriormente, o ensaio com ΔK constante e R crescente para ser utilizado no estudo da inferência de carregamento de amplitude constante a partir da relação entre a morfologia da estria, H/s e a razão de carregamento R. Adicionalmente foram realizados ensaios de tenacidade à fratura, nas direções L-T e T-L, conforme a norma ASTME1820 (1999). As taxas de propagação macroscópica e microscópica foram comparadas e boas correlações foram obtidas para um intervalo entre 0,1 a 1,0 μm/ciclo, mesmo com distintos R. Através da técnica proposta por Berkovitz (1995), o espectro de carregamento foi estimado para distintos valores de R, através da técnica de parametrização do fator K e os resultados foram comparados ao espectro de carregamento real imposto pela máquina de ensaio. Após os ensaios de amplitude constante de carregamento foram realizados ensaios de amplitude variável com a aplicação em corpos de prova M(T) de espectros de vôos simulados padronizados pela NLR do tipo Twist e Falstaff e seus vôos reduzidos, mini-Twist e mini- Falstaff, em uma máquina servohidráulica de ensaios dinâmicos. A partir destes ensaios notou-se que suprimir os vôos com os carregamentos menos severos influencia muito a vida da propagação da trinca de fadiga, quando vôos simulados do tipo Twist e mini-Twist, fato este não observado para o Falstaff e mini-Falstaff. Foi possível observar também o efeito da aceleração e desaceleração da trinca por fadiga observando os gráficos de d2a/dvôo vs. a obtidos dos ensaios de amplitude variável. Foi realizado um estudo da superfície de fratura do CP05 por meio da técnica fractográfica do reconhecimento de blocos marcadores sendo possível mostrar uma satisfatória reconstituição da taxa de propagação da trinca por fadiga de vôo simulado do tipo Falstaff por meio de medidas das marcações na superfície de fratura dos vôos mais severos, realizadas em imagens obtidas por MEV. / The loading inference and the fractographic reconstruction of fatigue crack propagation rate in simulated flight stories, as Twist, mini-Twist, Falstaff and mini-Falstaff were investigated in this work. The studied material was an aluminum alloy SAE-AMS 7475 T7351. Tensile and hardness tests were carried out in order to determine mechanical properties, as well as chemical and microstructure analysis of the material. C(T) specimens were extracted from a block of material for constant amplitude load testing and M(T) specimens were extracted from a plate and were tested in variable amplitude loading. The curves (da/dN vs. ΔK) for constant-amplitude loading were obtained from fatigue crack propagation tests performed in L-T and T-L directions in C(T) specimens for R (0.1; 0.3; 0.5; 0.7 and 0.8), at room temperature, according to ASTM-E647 (1993). Two different constant loading fatigue tests were performed. At constant ΔP and distinct values of R for obtaining data of stages II and III of da/dN - ΔK curves; and at constant ΔK and increasing the R ratio to be used in the inference of constant amplitude loading in the relation of H/s striation morphology (obtained from fractographic images) and the loading ratio, R. Additionally, fracture toughness tests were executed in T-L and L-T directions, according to ASTM-E1820 (1999). The macroscopic and microscopic fatigue crack propagations were compared and good correlation was obtained for the range 0.1-1.0 μm/cycle, for all R values. By using the K factor parametrization method, Berkovitz (1995), the loading spectrum was estimated for the distinct R-values and the results were compared to the actual spectrum imposed by the test machine. Variable amplitude tests were performed in M(T) specimens by applying simulating flight spectra normalized by NLR, as Twist, mini-Twist, Falstaff and mini-Falstaff, in a servohydraulic test machine MTS, in which a Flextest GT controller was coupled. The suppression of less severe loading flights showed a great influence in fatigue crack propagation life, in simulated flight tests Twist and mini-Twist, but not in Falstaff and mini-Falstaff. The acceleration and slowing down of fatigue crack were observed in the d2a/dflight - a curve obtained from variable loading tests. The fractured surfaces of some samples were examined by the fractographic technique of blocking marks recognition. A good reconstitution of fatigue crack propagation rate of a simulated flight like Falstaff was obtained by the measurements of marks in the fracture surfaces of the more severe flights, in MEV images.
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Proposta metodol?gica para o imageamento, caracteriza??o, parametriza??o e gera??o de modelos virtuais de afloramentosSouza, Anderson de Medeiros 31 January 2013 (has links)
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Previous issue date: 2013-01-31 / Petr?leo Brasileiro SA - PETROBRAS / The aim of this work was to describe the methodological procedures that were
mandatory to develop a 3D digital imaging of the external and internal geometry of the analogue
outcrops from reservoirs and to build a Virtual Outcrop Model (VOM). The imaging process of
the external geometry was acquired by using the Laser Scanner, the Geodesic GPS and the
Total Station procedures. On the other hand, the imaging of the internal geometry was
evaluated by GPR (Ground Penetrating Radar).The produced VOMs were adapted with much
more detailed data with addition of the geological data and the gamma ray and permeability
profiles. As a model for the use of the methodological procedures used on this work, the
adapted VOM, two outcrops, located at the east part of the Parnaiba Basin, were selected. On
the first one, rocks from the aeolian deposit of the Piaui Formation (Neo-carboniferous) and tidal
flat deposits from the Pedra de Fogo Formation (Permian), which arises in a large outcrops
located between Floriano and Teresina (Piau?), are present. The second area, located at the
National Park of Sete Cidades, also at the Piau?, presents rocks from the Cabe?as Formation
deposited in fluvial-deltaic systems during the Late Devonian. From the data of the adapted
VOMs it was possible to identify lines, surfaces and 3D geometry, and therefore, quantify the
geometry of interest. Among the found parameterization values, a table containing the thickness
and width, obtained in canal and lobes deposits at the outcrop Pared?o and Biblioteca were the
more relevant ones. In fact, this table can be used as an input for stochastic simulation of
reservoirs. An example of the direct use of such table and their predicted radargrams was the
identification of the bounding surface at the aeolian sites from the Piau? Formation. In spite of
such radargrams supply only bi-dimensional data, the acquired lines followed of a mesh profile
were used to add a third dimension to the imaging of the internal geometry. This phenomenon
appears to be valid for all studied outcrops. As a conclusion, the tool here presented can
became a new methodology in which the advantages of the digital imaging acquired from the
Laser Scanner (precision, accuracy and speed of acquisition) were combined with the Total
Station procedure (precision) using the classical digital photomosaic technique / Neste trabalho s?o apresentados os procedimentos metodol?gicos necess?rios para
realizar o imageamento digital 3D da geometria externa e interna de afloramentos an?logos a
reservat?rios, e elaborar seus Modelos Virtuais de Afloramentos (MVA). Para imagear a
geometria externa foram utilizados o Laser Scanner, o GPS Geod?sico e a Esta??o Total,
enquanto que para imagear a geometria interna foi utilizado o GPR. Nos MVA elaborados
foram acrescidas ainda as informa??es geol?gicas e as obtidas nas perfilagens com raios
gama e de permeabilidade. Como estudo de caso, para exemplificar os procedimentos
metodol?gicos propostos, foram escolhidos dois conjuntos de afloramentos na borda leste da
Bacia do Parna?ba. Na primeira ?rea ocorrem rochas de origem e?lica da Forma??o Piau?
(Neocarbon?fero) e plan?cie de mar? da Forma??o Pedra de Fogo (Permiano), que afloram em
um amplo corte de estrada, situado entre Floriano e Teresina (Piau?). A segunda ?rea, situada
no Parque Nacional de Sete Cidades, tamb?m no Piau?, envolve rochas da Forma??o Cabe?as
depositadas em sistemas fl?vio-deltaicos, durante o Neodevoniano. Com os MVA elaborados
foi poss?vel identificar, linhas, superf?cies e geometrias 3D e, assim, quantificar as geometrias
de interesse. Dentre as parametriza??es mais relevantes, ressaltam-se a tabela com valores de
espessura e largura, obtidas em dep?sitos de canais e em lobos, nos afloramentos Pared?o e
Biblioteca. Esta tabela pode ser utilizada como entrada (input) para simula??o estoc?stica de
reservat?rios. Um exemplo da aplica??o direta dos radargramas interpretados foi a
identifica??o de superf?cies limitantes, em dep?sitos e?licos, da Forma??o Piau?. Apesar dos
radargramas oferecerem apenas dados bidimensionais, a aquisi??o de linhas distribu?das
segundo uma malha acrescentou a terceira dimens?o ao imageamento das geometrias
internas em todos os afloramentos estudados. ? ainda proposta uma nova metodologia que
busca conciliar as vantagens obtidas com o imageamento digital com Laser Scanner (precis?o,
acur?cia e velocidade de aquisi??o) e a Esta??o Total (precis?o), com o uso cl?ssico de
fotomosaicos digitais
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Estudo da inferência de carregamento em histórias de vôos simulados na liga de Al aeronáutico SAE-AMS 7475 T7351 / Loading study of inference in a simulated flights history using an SAE-AMS 7475 T7351 aluminum alloy.Cassius Olivio Figueiredo Terra Ruchert 28 March 2007 (has links)
Este trabalho discutiu o estudo da inferência de carregamento e a reconstrução fratográfica da taxa de propagação da trinca por fadiga em histórias de vôos simulados do tipo Twist, mini-Twist, Falstaff e mini-Falstaff. O material estudado foi uma liga de alumínio de grau aeronáutico SAE-AMS 7475 T7351 na qual foram obtidas as propriedades mecânicas a partir dos ensaios de tração e dureza, análise química, metalográfica. Foram realizados ensaios de amplitude constante de carregamento em corpos de prova com geometria tipo C(T) extraídos de um bloco e ensaios de amplitude variável em corpos de prova com geometria tipo M(T) extraídos de uma placa. Corpos de prova do tipo C(T) foram extraídos da orientação L-T e T-L, à temperatura ambiente com diferentes espessuras para a realização de ensaios de propagação de trinca por fadiga (da/dN vs. ΔK) com distintos valores de razão de carregamento,R (0,1;0,3; 0,5; 0,7 e 0,8) de acordo com a norma ASTM-E647 (1993). Foram realizados dois tipos de ensaios de fadiga com amplitude constante de carregamento. Primeiro, o ensaio com ΔP constante para obtenção dos dados dos estágios II e III das curvas da/dN vs. ΔK para distintos valores de R e, posteriormente, o ensaio com ΔK constante e R crescente para ser utilizado no estudo da inferência de carregamento de amplitude constante a partir da relação entre a morfologia da estria, H/s e a razão de carregamento R. Adicionalmente foram realizados ensaios de tenacidade à fratura, nas direções L-T e T-L, conforme a norma ASTME1820 (1999). As taxas de propagação macroscópica e microscópica foram comparadas e boas correlações foram obtidas para um intervalo entre 0,1 a 1,0 μm/ciclo, mesmo com distintos R. Através da técnica proposta por Berkovitz (1995), o espectro de carregamento foi estimado para distintos valores de R, através da técnica de parametrização do fator K e os resultados foram comparados ao espectro de carregamento real imposto pela máquina de ensaio. Após os ensaios de amplitude constante de carregamento foram realizados ensaios de amplitude variável com a aplicação em corpos de prova M(T) de espectros de vôos simulados padronizados pela NLR do tipo Twist e Falstaff e seus vôos reduzidos, mini-Twist e mini- Falstaff, em uma máquina servohidráulica de ensaios dinâmicos. A partir destes ensaios notou-se que suprimir os vôos com os carregamentos menos severos influencia muito a vida da propagação da trinca de fadiga, quando vôos simulados do tipo Twist e mini-Twist, fato este não observado para o Falstaff e mini-Falstaff. Foi possível observar também o efeito da aceleração e desaceleração da trinca por fadiga observando os gráficos de d2a/dvôo vs. a obtidos dos ensaios de amplitude variável. Foi realizado um estudo da superfície de fratura do CP05 por meio da técnica fractográfica do reconhecimento de blocos marcadores sendo possível mostrar uma satisfatória reconstituição da taxa de propagação da trinca por fadiga de vôo simulado do tipo Falstaff por meio de medidas das marcações na superfície de fratura dos vôos mais severos, realizadas em imagens obtidas por MEV. / The loading inference and the fractographic reconstruction of fatigue crack propagation rate in simulated flight stories, as Twist, mini-Twist, Falstaff and mini-Falstaff were investigated in this work. The studied material was an aluminum alloy SAE-AMS 7475 T7351. Tensile and hardness tests were carried out in order to determine mechanical properties, as well as chemical and microstructure analysis of the material. C(T) specimens were extracted from a block of material for constant amplitude load testing and M(T) specimens were extracted from a plate and were tested in variable amplitude loading. The curves (da/dN vs. ΔK) for constant-amplitude loading were obtained from fatigue crack propagation tests performed in L-T and T-L directions in C(T) specimens for R (0.1; 0.3; 0.5; 0.7 and 0.8), at room temperature, according to ASTM-E647 (1993). Two different constant loading fatigue tests were performed. At constant ΔP and distinct values of R for obtaining data of stages II and III of da/dN - ΔK curves; and at constant ΔK and increasing the R ratio to be used in the inference of constant amplitude loading in the relation of H/s striation morphology (obtained from fractographic images) and the loading ratio, R. Additionally, fracture toughness tests were executed in T-L and L-T directions, according to ASTM-E1820 (1999). The macroscopic and microscopic fatigue crack propagations were compared and good correlation was obtained for the range 0.1-1.0 μm/cycle, for all R values. By using the K factor parametrization method, Berkovitz (1995), the loading spectrum was estimated for the distinct R-values and the results were compared to the actual spectrum imposed by the test machine. Variable amplitude tests were performed in M(T) specimens by applying simulating flight spectra normalized by NLR, as Twist, mini-Twist, Falstaff and mini-Falstaff, in a servohydraulic test machine MTS, in which a Flextest GT controller was coupled. The suppression of less severe loading flights showed a great influence in fatigue crack propagation life, in simulated flight tests Twist and mini-Twist, but not in Falstaff and mini-Falstaff. The acceleration and slowing down of fatigue crack were observed in the d2a/dflight - a curve obtained from variable loading tests. The fractured surfaces of some samples were examined by the fractographic technique of blocking marks recognition. A good reconstitution of fatigue crack propagation rate of a simulated flight like Falstaff was obtained by the measurements of marks in the fracture surfaces of the more severe flights, in MEV images.
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Výzkum pokročilých metod analýzy online písma se zaměřením na hodnocení grafomotorických obtíží u dětí školního věku / Research of Advanced Online Handwriting Analysis Methods with a Special Focus on Assessment of Graphomotor Disabilities in School-aged ChildrenZvončák, Vojtěch January 2021 (has links)
Grafomotorické dovednosti (GA) představují skupinu psychomotorických procesů, které se zapojují během kreslení a psaní. GA jsou nutnou prerekvizitou pro zvládání základních školních schopností, konkrétně psaní. Děti v první a druhé třídě mohou mít potíže s prováděním jednoduchých grafomotorických úkolů (GD) a později ve třetí a čtvrté třídě také se samotným psaním (HD). Narušení procesů spojených se psaním je obecně nazýváno jako vývojová dysgrafie (DD). Prevalence DD v České republice se pohybuje kolem 3–5 %. V současné době je DD hodnocena subjektivně týmem psychologů a speciálních pedagogů. V praxi stále chybí objektivní měřicí nástroj, který by umožňoval hodnocení GD a HD. Z tohoto důvodu se tato disertační práce zabývá identifikováním symptomů spojených s grafomotorickou neobratností u dětí školního věku a vývojem nových parametrů, které je budou kvantifikovat. Byl vytvořen komplexní GA protokol (36 úloh), který představuje prostředí, ve kterém se mohou projevit různé symptomy spojené s GD a HD. K těmto symptomům bylo přiřazeno 76 kvantifikujících parametrů. Dále byla navrhnuta nová škála grafomotorických obtíží (GDRS) založena na automatizovaném zpracování online píma. Nakonec byla prezentována a otestována nová sada parametrizačních technik založených na Tunable Q Factor Wavelet Transform (TQWT). Parametry TQWT dokážou kvantifikovat grafomotorickou obratnost nebo nedostatečný projev v jemné motorice. GDRS přestavuje nový, moderní a objektivní měřící nástroj, který doposud chyběl jak v České republice, tak v zahraničí. Použití škály by pomohlo modernizovat jak diagnostiku DD, tak reedukační/remediační proces. Další výzkum by tento nástroj mohl adaptovat i do jiných jazyků. Navíc, tato metodologie může být použita a optimalizována pro diagnostiku dalších nemocí a poruch, které ovlivňují grafomotorické dovednosti, například pro autismus, poruchu pozornosti s hyperaktivitou (ADHD) nebo dyspraxii (DCD).
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Shape Optimization to improve NVH of an IPM machine for heavy vehicle applications : Setup and evaluation of an optimization framework through comparisons with results from shape parametrization study for NVH / Formoptimering och NVH analys av en IPM-maskin som används i tunga fordonsapplikationerSriram, Shravan January 2024 (has links)
The thesis evaluates the potential of shape optimization to provide electric machine geometries that are optimized for torque, noise, vibration and harshness (NVH) and efficiency. It could be an alternative to the parametrization-based approach in the electric machine design process. In this work, an optimization framework was developed using Altair Flux-2D™ and MATLAB™ software, with mean radial tooth force (MRTF) and torque as responses. Various features of an interior permanent magnet machine (IPM) machine were selected for optimization, such as rotor surface, outer magnet air-pockets, stator tooth-tips, and shape features along the d-axis and q-axis of the machine. A shape-parametrization study was performed to further understand the results obtained from the shape-optimization framework. During this study, it was observed that the MRTF harmonic of radial tooth forces represented in the complex domain could be modified by changing the shape dimension and position. Cases were created, wherein different types of bumps and notches were introduced on the rotor surface and stator tooth-tips, after which, a design of experiments (DOE) study modified them to observe their influence on the MRTF harmonic. Shape optimization provided results much faster than DOE-based studies, and it was best suited to suggest minor changes and offer additional performance improvements. In a parametrization-based design process, shape optimization could be used effectively in the latter stages as a design evaluation and enhancement tool. Results from the framework indicated that efficiency must be sacrificed to achieve a sizeable reduction in the MRTF harmonic. The latter is most sensitive to shape changes on the rotor surface, while partial radial-force vector modification is possible by changing the shape of that toothtip. When correctly placed, bumps and notches offer good MRTF harmonic and torque ripple reductions. / Avhandlingen utvärderar potentialen för formoptimering för att tillhandahålla elektriska maskingeometrier som är optimerade för vridmoment, NVH och effektivitet. Det kan vara ett alternativ till den parametriseringsbaserade metoden i designprocessen för elektriska maskiner. I detta arbete utvecklades ett optimeringsramverk med flera mål med hjälp av Altair Flux-2D™ och MATLAB™ mjukvara, med MRTF och vridmoment som svar. Olika funktioner hos en IPM-maskin valdes ut för optimering, såsom rotoryta, yttre magnetiska luftfickor, statortandspetsar och formegenskaper längs maskinens d-axel och q-axel. En formparametriseringsstudie utfördes för att ytterligare förstå resultaten från formoptimeringsramverket. Under denna studie observerades det att MRTF-harmoniken för radiella tandkrafter representerade i den komplexa domänen kunde modifieras genom att ändra formdimensionen och positionen. Fall skapades, där olika typer av stötar och skåror introducerades på rotorytan och statortandspetsarna, varefter en DOE-studie modifierade dem för att observera deras inverkan på MRTF-övertonen. Formoptimering gav resultat mycket snabbare än DOE-baserade studier, och den var bäst lämpad för att föreslå mindre förändringar och erbjuda ytterligare prestandaförbättringar. I en parametriseringsbaserad designprocess kan formoptimering användas effektivt i de senare stadierna som ett verktyg för designutvärdering och förbättring. Resultat från ramverket indikerade att effektivitet måste offras för att uppnå en avsevärd minskning av MRTF-övertonen. Den senare är mest känslig för formförändringar på rotorytan, medan partiell radialkraftvektormodifiering är möjlig genom att ändra formen på den tandspetsen. När de är korrekt placerade ger stötar och skåror bra MRTF-harmoniska och vridmoment-rippelreduktioner.
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