Vortex-identification methods from a different perspective

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985840%3A_____%2F18%3A00496425" target="_blank" >RIV/67985840:_____/18:00496425 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/67985874:_____/18:00496425

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Vortex-identification methods from a different perspective

Popis výsledku v původním jazyce

A more universal classification of vortex-identification methods starts with the basic fluid-mechanical approach adopted: Lagrangian or Eulerian. Eulerian methods can be further sub-classified as local (pointwise) or non-local. The Eulerian local methods aim either at the vortex volumetric region (region-type schemes) or at the vortexcore skeleton (line-type schemes). Most of the Eulerian region-type methods (including some Lagrangian) are based on one vortex feature to derive a yes/no criterion which may provide the intensity measure of local vortex motion inside the vortex region, however, no applicable quantitative information outside the vortex region. The present paper aims to distinguish and emphasize those vortex-identification tools which are simultaneously and adequately informative outside the vortex regions, that is, basically covering the whole flow domain and especially indicating regions of strong strain-rate or shearing. This is due to a certain duality property of criterial measures applied (Q-criterion, MZ-criterion) or due to a rational velocity-gradient analysis of a wider applicability (triple decomposition method, corotation/contrarotation scheme). The latter provide complex information at each point of the flow field while the former distinguish two or more qualitatively different non-overlapping flow regions. Some illustrative vortical-flow examples are included.

Název v anglickém jazyce

Vortex-identification methods from a different perspective

Popis výsledku anglicky

A more universal classification of vortex-identification methods starts with the basic fluid-mechanical approach adopted: Lagrangian or Eulerian. Eulerian methods can be further sub-classified as local (pointwise) or non-local. The Eulerian local methods aim either at the vortex volumetric region (region-type schemes) or at the vortexcore skeleton (line-type schemes). Most of the Eulerian region-type methods (including some Lagrangian) are based on one vortex feature to derive a yes/no criterion which may provide the intensity measure of local vortex motion inside the vortex region, however, no applicable quantitative information outside the vortex region. The present paper aims to distinguish and emphasize those vortex-identification tools which are simultaneously and adequately informative outside the vortex regions, that is, basically covering the whole flow domain and especially indicating regions of strong strain-rate or shearing. This is due to a certain duality property of criterial measures applied (Q-criterion, MZ-criterion) or due to a rational velocity-gradient analysis of a wider applicability (triple decomposition method, corotation/contrarotation scheme). The latter provide complex information at each point of the flow field while the former distinguish two or more qualitatively different non-overlapping flow regions. Some illustrative vortical-flow examples are included.

Druh

O - Ostatní výsledky

CEP obor

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OECD FORD obor

10101 - Pure mathematics

Projekt

<a href="/cs/project/GA18-09628S" target="_blank" >GA18-09628S: Pokročilá analýza proudových polí</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů