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| − | ==1 Title, abstract and keywords<!-- Your document should start with a concise and informative title. Titles are often used in information-retrieval systems. Avoid abbreviations and formulae where possible. Capitalize the first word of the title. | + | ==Abstract== |
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| − | Provide a maximum of 6 keywords, and avoiding general and plural terms and multiple concepts (avoid, for example, 'and', 'of'). Be sparing with abbreviations: only abbreviations firmly established in the field should be used. These keywords will be used for indexing purposes.
| + | In this work we design and analyze pressure segregation methods in order to approximate |
| | + | the Navier-Stokes equations. Pressure correction methods are widely used because they |
| | + | allow the decoupling of velocity and pressure computation, decreasing the computational |
| | + | cost. We have analyzed some of these schemes, obtaining inherent pressure stability. |
| | + | However, for second order accurate methods (in time) this inherent stability is too weak, |
| | + | requiring the introduction of a stabilized finite element methodology for the space discretization. Moreover, we have carried out a complete convergence analysis of a first order |
| | + | pressure segregation method. |
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| − | An abstract is required for every document; it should succinctly summarize the reason for the work, the main findings, and the conclusions of the study. Abstract is often presented separately from the article, so it must be able to stand alone. For this reason, references and hyperlinks should be avoided. If references are essential, then cite the author(s) and year(s). Also, non-standard or uncommon abbreviations should be avoided, but if essential they must be defined at their first mention in the abstract itself. -->==
| + | We have used a stabilization technique justified from a multiscale approach that allows |
| | + | the use of equal velocity-pressure interpolation spaces and convection dominated flows. |
| | + | A new kind of methods has been motivated from an alternative version of the monolithic fluid solver where the continuity equation is replaced by a discrete pressure Poisson |
| | + | equation. These methods belong to the family of velocity correction schemes, where it |
| | + | is the velocity instead of the pressure the extrapolated unknown. Some stability bounds |
| | + | have been proved, revealing that their inherent pressure stability is too weak. Further, |
| | + | predictor corrector schemes easily arise from the new monolithic system. Numerical ex- |
| | + | perimentation shows the good behavior of these methods. |
| | | | |
| | + | We have introduced the ALE framework in order for the fluid governing equations to |
| | + | be formulated on moving domains. Taking as the model equation the convection-di®usion |
| | + | equation, we have analyzed the blend of the ALE framework and a stabilized finite element |
| | + | method. |
| | | | |
| | + | We suggest a coupling procedure for the fluid-structure problem taking benefit from |
| | + | the ingredients previously introduced: pressure segregation methods, a stabilized finite |
| | + | element formulation and the ALE framework. The final algorithm, using one loop, tends |
| | + | to the monolithic (fluid-structure) system. |
| | | | |
| | + | This method has been applied to the simulation of bridge aerodynamics, obtaining a |
| | + | good convergence behavior. |
| | | | |
| − | ==2 The main text<!-- You can enter and format the text of this document by selecting the ‘Edit’ option in the menu at the top of this frame or next to the title of every section of the document. This will give access to the visual editor. Alternatively, you can edit the source of this document (Wiki markup format) by selecting the ‘Edit source’ option.
| + | We end with the simulation of wind turbines. The fact that we have a rotary body |
| | + | surrounded by the fluid (air) has motivated the introduction of a remeshing strategy. We |
| | + | consider a selective remeshing procedure that only affects a tiny portion of the domain, |
| | + | with little impact on the overall CPU time. |
| | | | |
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| − | | + | <pdf>Media:Draft_Samper_174020244_4860_M96.pdf</pdf> |
| − | 2.1 Subsections
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| − | Divide your article into clearly defined and numbered sections. Subsections should be numbered 1.1, 1.2, etc. and then 1.1.1, 1.1.2, ... Use this numbering also for internal cross-referencing: do not just refer to 'the text'. Any subsection may be given a brief heading. Capitalize the first word of the headings.
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| − | 2.2 General guidelines
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| − | Please insert tables as editable text and not as images. Tables should be placed next to the relevant text in the article. Number tables consecutively in accordance with their appearance in the text and place any table notes below the table body. Be sparing in the use of tables and ensure that the data presented in them do not duplicate results described elsewhere in the article.
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| − | For tabular summations that do not deserve to be presented as a table, lists are often used. Lists may be either numbered or bulleted. Below you see examples of both.
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| − | You may choose to number equations for easy referencing. In that case they must be numbered consecutively with Arabic numerals in parentheses on the right hand side of the page. Below is an example of formulae that should be referenced as eq. (1].
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| − | 2.4 Supplementary material
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| − | Supplementary material can be inserted to support and enhance your article. This includes video material, animation sequences, background datasets, computational models, sound clips and more. In order to ensure that your material is directly usable, please provide the files with a preferred maximum size of 50 MB. Please supply a concise and descriptive caption for each file. -->==
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| − | ==3 Bibliography<!--
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| − | Citations in text will follow a citation-sequence system (i.e. sources are numbered by order of reference so that the first reference cited in the document is [1], the second [2], and so on) with the number of the reference in square brackets. Once a source has been cited, the same number is used in all subsequent references. If the numbers are not in a continuous sequence, use commas (with no spaces) between numbers. If you have more than two numbers in a continuous sequence, use the first and last number of the sequence joined by a hyphen
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| − | ==4 Acknowledgments<!-- Acknowledgments should be inserted at the end of the document, before the references section. -->==
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| − | ==5 References<!--[1] Author, A. and Author, B. (Year) Title of the article. Title of the Publication. Article code. Available: http://www.scipedia.com/ucode.
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| − | [2] Author, A. and Author, B. (Year) Title of the article. Title of the Publication. Volume number, first page-last page.
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| − | [5] Author, E. (Year, Month date). Title of the article. In A. Editor, B. Editor, and C. Editor. Title of published proceedings. Paper presented at title of conference, Volume number, first page-last page. Place of publication.
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| − | [6] Institution or author. Title of the document. Year. [Online] (Date consulted: day, month and year). Available: http://www.scipedia.com/document.pdf.
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In this work we design and analyze pressure segregation methods in order to approximate
the Navier-Stokes equations. Pressure correction methods are widely used because they
allow the decoupling of velocity and pressure computation, decreasing the computational
cost. We have analyzed some of these schemes, obtaining inherent pressure stability.
However, for second order accurate methods (in time) this inherent stability is too weak,
requiring the introduction of a stabilized finite element methodology for the space discretization. Moreover, we have carried out a complete convergence analysis of a first order
pressure segregation method.
We have used a stabilization technique justified from a multiscale approach that allows
the use of equal velocity-pressure interpolation spaces and convection dominated flows.
A new kind of methods has been motivated from an alternative version of the monolithic fluid solver where the continuity equation is replaced by a discrete pressure Poisson
equation. These methods belong to the family of velocity correction schemes, where it
is the velocity instead of the pressure the extrapolated unknown. Some stability bounds
have been proved, revealing that their inherent pressure stability is too weak. Further,
predictor corrector schemes easily arise from the new monolithic system. Numerical ex-
perimentation shows the good behavior of these methods.
We have introduced the ALE framework in order for the fluid governing equations to
be formulated on moving domains. Taking as the model equation the convection-di®usion
equation, we have analyzed the blend of the ALE framework and a stabilized finite element
method.
We suggest a coupling procedure for the fluid-structure problem taking benefit from
the ingredients previously introduced: pressure segregation methods, a stabilized finite
element formulation and the ALE framework. The final algorithm, using one loop, tends
to the monolithic (fluid-structure) system.
This method has been applied to the simulation of bridge aerodynamics, obtaining a
good convergence behavior.
We end with the simulation of wind turbines. The fact that we have a rotary body
surrounded by the fluid (air) has motivated the introduction of a remeshing strategy. We
consider a selective remeshing procedure that only affects a tiny portion of the domain,
with little impact on the overall CPU time.
