6,775 research outputs found
Study of Transition Prediction with the Langtry-Menter Model in the Tau Rans Flow Solver
No full text[EN] In this report a new approach for transition prediction is reviewed. The Langtry-Menter
model is a new approach that is based only in local variables what makes it easy to use in
modern CFD parallelised codes with unstructured grids. A complete review of the model,
the mathematical formulation and the coupling with the turbulent model is presented.
The extension of the model to 3D cases with crossflow and previous work done on the
Langtry-Menter transition model is summarised.
The methodology to run the Langtry-Menter transition model coupled with the tur bulent model k −ω SST is developed and the Best Practice is established. Experimental
data for a natural laminar flow wing, model M2355, is used to validate the model and the
limits of the transition model in the TAU flow solver are checked. The original transition
model is developed with a 2D boundary layer profile so a 0° sweep angle case is chosen
as an appropriate example.
The input, key parameters and mesh sensitivity are studied with three different meshes
and how to set up the key parameters is reviewed. Different variables like first cell high,
surface mesh size or farfield mesh maximum size are changed in the base mesh to com pare both results and see its influence on the final result. The sensitivity of the model to
the mesh and key parameters is shown and how that sensitivity affects the accuracy and
robustness of the final solution is presented. A detailed analysis of the model has been
performed investigating the behavior of certain flow features that appear in the solution,
specially when the transition model is switched onHernández López, A. (2013). Study of Transition Prediction with the Langtry-Menter Model in the Tau Rans Flow Solver. https://riunet.upv.es/handle/10251/178737Archivo delegad
[Poesia] Três poemas de Alberto Secama
No full textThree poems by Alberto Secama. About the author: Alberto Secama is an Angolan poet who has poems published on many websites and on facebook:https://www.facebook.com/Xungurra/abouthttp://www.pordentrodaafrica.com/cultura/africa-em-verso-rio-kwanza-por-alberto-secamahttp://www.pordentrodaafrica.com/cultura/africa-em-verso-zong-por-alberto-secamahttp://www.pordentrodaafrica.com/cultura/coluna-africa-em-verso-o-sol-la-fora-por-alberto-secamaTres poemas de Alberto Secama. Sobre el autor: Alberto Secama es un poeta angoleño que tiene poemas publicados en varios sitios y en el facebook:https://www.facebook.com/Xungurra/abouthttp://www.pordentrodaafrica.com/cultura/africa-em-verso-rio-kwanza-por-alberto-secamahttp://www.pordentrodaafrica.com/cultura/africa-em-verso-zong-por-alberto-secamahttp://www.pordentrodaafrica.com/cultura/coluna-africa-em-verso-o-sol-la-fora-por-alberto-secamaTrês poemas de Alberto Secama. Sobre o autor: Alberto Secama é um poeta angolano que possui poemas publicados em vários sites e no facebook:https://www.facebook.com/Xungurra/abouthttp://www.pordentrodaafrica.com/cultura/africa-em-verso-rio-kwanza-por-alberto-secamahttp://www.pordentrodaafrica.com/cultura/africa-em-verso-zong-por-alberto-secamahttp://www.pordentrodaafrica.com/cultura/coluna-africa-em-verso-o-sol-la-fora-por-alberto-secam
Orizzonti mantovani. Spunti e dinamiche paesaggistiche ne L'Illustrissimo di Alberto Cantoni
No full textIn the literary production of Alberto Cantoni, short story writer and novelist between the nineteenth and twentieth centuries, the novel L'Illustrissimo is highly important both because it is the last publication of the author, from Pomponesco, a small town a few kilometers south of Mantua, both because it summarizes in a single text the different nuances and different directions that his writing has taken over the course of his literary career, also due to a writing and processing time that embraces the entire span of years of his career itself. In the foreground, in addition to the numerous and brilliant characters, one of the protagonists is the Mantuan landscape which, not a simple background, becomes a true literary parameter which in different and significant ways affects the purposes and mechanisms of the novel
Langtry-Menter 4-Equation transition model : SU2 implementation, validation and verification
No full textLAUREA MAGISTRALELe simulazioni in cui si verificano processi di transizione da regime laminare a turbolento rappresentano una grande sfida nell'ambito della CFD moderna. L'argomento della transizione, studiato da decenni, è ancora aperto a nuove soluzioni e miglioramenti. I moderni framework di CFD fanno un uso intensivo di calcolo parallelo e si basano su griglie non strutturate. DNS e LES sono strumenti adeguati alla simulazione della transizione, ma sfortunatamente hanno costi troppo elevati per le applicazioni ingegneristiche. Vengono usati principalmente come strumenti di ricerca o come sostituti nel caso di esperimenti controllati. Le equazioni RANS rimangono gli strumenti più indicati in cui implementare dei modelli di transizione che siano pienamente compatibili con la CFD moderna. La vera e propria sfida è quindi la formulazione di un modello che possa essere integrato in un framework CFD già esistente. Il lavoro qui sviluppato ha l'obiettivo di implementare il modello di transizione a quattro equazioni di Langtry e Menter (LM) per poi successivamente validarlo e verificarne l'accuratezza rispetto a dei casi notevoli. Questo modello di transizione è basato su correlazioni e ha una formulazione locale, essendo quindi particolarmente adatto per metodi che usano calcolo parallelo e griglie non strutturate. Si considera la struttura standard in SU2 per le equazioni alle derivate parziali: due equazioni di trasporto, una per la funzione di intermittenza e una per il numero di Reynolds basato sullo spessore di quantità di moto di inizio transizione, vengono aggiunte alla già esistente implementazione del modello di turbolenza SST. Per validare il modello vengono effettuate simulazioni sia comprimibili che incomprimibili di configurazioni 2D stazionarie e instazionarie. Casi di lastra piana, profilo alare Eppler E387 e NACA0021 sono significativi da questo punto di vista. I risultati ottenuti con il modello LM vengono confrontati con i dati sperimentali. Anche i risultati ottenuti con il già implementato modello di trasizione di Bas e Cakmakcioglu (BC) vengono sfruttati per capire il comportamento del muovo modello LM in relazione a esso. Successivamente una geometria 3D fornita da Airbus, nell'ambito del progetto MONNALISA, viene usata per verificarne l'accuratezza rispetto ai risultati del modello BC ottenuti nel progetto. Alla fine, vengono presentate le conclusioni, così come alcuni possibili futuri miglioramenti e estensioni all'implementazione scelta per questo lavoro di tesi.Simulations on transitional flows represent a big challenge in the scope of modern Computational Fluid Dynamics (CFD) methods. The transition problem, addressed for decades, is still open to new solutions and improvements. Modern CFD frameworks make massive use of parallel computing and are based on unstructured grids. Direct Numerical Simulations (DNS) and Large Eddy Simulations (LES) are suitable tools for transition prediction, but unfortunately are too far costly for engineering applications. They are used mainly as research tools and substitutes for controlled experiments. So Reynolds-Averaged Navier-Stokes (RANS) equations remain the most indicated methods for implementing a fully modern-CFD-compatible transition model. The very proper challenge is in the formulation of a model that can be integrated in an already existing CFD framework. The present work aims at implementing within the SU2 framework the "Langtry-Menter" (LM) 4-equation transition model to successively validate and verify it against notable test cases. This transition model is a local correlation-based one, particularly suited for methods that uses parallel computation and unstructured grids. The SU2 standard structure for Partial Differential Equations (PDEs) is considered: two transport equations, one for the intermittency and one for the transition onset momentum-thickness Reynolds number, are added to the already existing Shear-Stress Transport (SST) turbulence model implementation. Both compressible and incompressible simulations on steady and unsteady two-dimensional (2D) configurations are then performed to validate the model. Flat-plate, Eppler E387- and NACA0021-airfoil test cases are meaningful from this point of view. Comparisons are made between LM results and experimental data. Also results obtained with the SU2 built-in Bas-Cakmakcioglu (BC) transition model are exploited to understand the behaviour of the new-implemented LM model with respect to it. Successively a three-dimensional (3D) geometry provided by Airbus, in the context of the MONNALISA project, is used to verify the model against BC results obtained from that project. In the end, conclusions are provided, as well as some future possible improvements and extensions to the implementation chosen for this thesis work
Plenary Session: Luis Alberto Urrea
No full texta) Plenary Session: Luis Alberto Urrea, Mexican American Chicago Writer
Luis Alberto Urrea is a 2005 Pulitzer Prize finalist for non-fiction and member of the Latino Literature Hall of Fame. He is a prolific and acclaimed writer who has used his dual-culture life border experiences to explore the complex and interconnected Mexican-US American reality. The critically acclaimed and best-selling Mexican-born author of 13 books, Urrea has won numerous awards for his poetry, fiction and essays.
Moderator: Dr. Héctor García, Loyola University Chicag
O duplo significado do sentir e do pensar nas obras de Alberto Caeiro e Descartes
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão. Programa de Pós-Graduação em LiteraturaA pretensão desta dissertação intitulada O duplo significado do sentir e do pensar nas obras de Alberto Caeiro e Descartes é investigar a relação entre o sentir e o puro pensar, usando como referência a poesia O Guardador de Rebanhos, de Alberto Caeiro, que apresenta de forma evidente o tema; e como este assunto é tratado nas Meditações Metafísicas de René Descartes, também de forma claramente visível. Podemos perceber em ambos os autores, uma diplopia, uma espécie de duplo olhar sobre a relação sentir e puro pensar. No primeiro capítulo vou falar sobre a tese do duplo olhar de Descartes, a respeito da relação sentir e puro pensar na leitura de Merleau-Ponty, salientando a visão de natureza. No segundo capítulo, parto da leitura das três primeiras Meditações Metafísicas para caracterizar a tensão que se pode verificar entre Descartes e Alberto Caeiro quando se referem ao puro pensar. O foco principal de Descartes, nas três primeiras Meditações, é o pensar puro, e neste ponto Alberto Caeiro critica o pensar puro. No terceiro capítulo, analisando as três últimas Meditações, percebe-se que há uma virada no pensamento de Descartes, no qual o autor inverte seu ponto de vista, aproximando-se da idéia de Alberto Caeiro. No quarto capítulo, mostrarei a leitura que outros autores fazem acerca do sentir e do pensar na obra de Alberto Caeiro, mostrando que assim como Descartes, este também ostenta uma diplopia, não do sentir, mas do pensar. The pretension of this work entitled O duplo significado do sentir e do pensar nas obras de Alberto Caeiro e Descartes is to investigate the relationship between the feeling and the pure thinking, using as reference the poetry O Guardador de Rebanhos, by Alberto Caeiro, that presents in an evident way this theme; and as this subject is treated in René Descartes' Metaphysical Meditations, also in a clearly visible way. It is possible to notice in both authors, the diplopy, a sort of double look about the relationship between feeling and pure thinking. The thesis about Descartes'double look regarding the relation of feeling and pure thinking, in Merleau-Ponty reading, pointing out the nature vision, will be treated in the first chapter. In the second chapter, I start from the reading of the first three Metaphysical Meditations to characterize the tension that can be verified between Descartes and Alberto Caeiro when they refer to the pure thinking. Descartes' main focus in the first three Meditations is pure thinking and, in this point, Alberto Caeiro criticizes pure thinking. In the third chapter, analyzing the last three Meditations, it is possible to notice that there is an alteration in Descartes' thought, in which the author inverts his point of view, approaching of Alberto Caeiro's idea. In the fourth chapter, I will show the reading that other authors do concerning feeling and thinking in Alberto Caeiro's work, showing that as well as Descartes, this also shows a diplopy, not of feeling, but of thinking
Lobbying for change as a new theory and practice of active citizenship: author interview with Alberto Alemanno
No full textDo you believe that lobbying is a vehicle for representing the interests of some rather than all, meaning its actors can never be a force for good? Alberto Alemanno, author of Lobbying for Change: Find Your Voice to Create a Better Society, might convince you of the contrary. This interview with Barbara Aubin, LSE Public Affairs, reflects on the importance of engaging with our political representatives, holding them accountable and lobbying for the causes we deeply care about as fundamental elements of a healthy democracy
Bibliografia di Umberto Romagnoli
No full textA complete bibliography of Umberto Romagnoli writings, introduced by a few lines by editors of the Journal and completed by an essay by Alberto Mattei dealing with some technical aspects of the collection of the
bibliography interwoven with some scholarly life moments of the author
Fray Alberto arquitecto (1575 – 1635): José Luis García Martínez y José Miguel Muñoz Jiménez
No full textMuch of the baroque architecture was the work of religious men of the we do not know, perhaps for being humility one of his necessary virtues. However, this ignorance is surprising in the case of the Carmelite Fray Alberto de la Madre de Dios, given his enormous stature and work, ignorance that has even sometimes turned into denial on the part of some uninformed author. And the thing is that he, of whom Chueca Goitia said that he had been the initiator of the Baroque in Castile, is the proven author of nearly eighty works and supposedly of as many others, as is more than accredited in the book reviewed here.Gran parte de la arquitectura barroca fue obra de religiosos de los que no sabemos su nombre, por ser quizá la humildad una de sus virtudes necesarias. Sorprende sin embargo esta ignorancia en el caso del carmelita Fray Alberto de la Madre de Dios, dada su enorme talla y obra, ignorancia que incluso en ocasiones se ha convertido en negación por parte de algún autor desinformado. Y es que aquel, de quien dijo Chueca Goitia que había sido el iniciador del Barroco en Castilla, es autor demostrado de cerca de ochenta obras y supuesto de otras tantas, como queda más que acreditado en el libro aquí reseñado
Fray Alberto arquitecto (1575 – 1635): José Luis García Martínez y José Miguel Muñoz Jiménez
No full textMuch of the baroque architecture was the work of religious men of the we do not know, perhaps for being humility one of his necessary virtues. However, this ignorance is surprising in the case of the Carmelite Fray Alberto de la Madre de Dios, given his enormous stature and work, ignorance that has even sometimes turned into denial on the part of some uninformed author. And the thing is that he, of whom Chueca Goitia said that he had been the initiator of the Baroque in Castile, is the proven author of nearly eighty works and supposedly of as many others, as is more than accredited in the book reviewed here.Gran parte de la arquitectura barroca fue obra de religiosos de los que no sabemos su nombre, por ser quizá la humildad una de sus virtudes necesarias. Sorprende sin embargo esta ignorancia en el caso del carmelita Fray Alberto de la Madre de Dios, dada su enorme talla y obra, ignorancia que incluso en ocasiones se ha convertido en negación por parte de algún autor desinformado. Y es que aquel, de quien dijo Chueca Goitia que había sido el iniciador del Barroco en Castilla, es autor demostrado de cerca de ochenta obras y supuesto de otras tantas, como queda más que acreditado en el libro aquí reseñado
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