Journal ArticleDOI
New normalized Rortex/vortex identification method
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TLDR
In this paper, a new vortex identification criterion, named ΩR, is proposed for the normalization of Rortex, using the idea of the Omega method (Ω), which is a normalized function from 0 to 1, which measures the relative rotation strength on the plane perpendicular to the local rotation axis.Abstract:
A new vortex identification criterion, named ΩR, is proposed for the normalization of Rortex, using the idea of the Omega method (Ω). ΩR is a normalized function from 0 to 1, which measures the relative rotation strength on the plane perpendicular to the local rotation axis. The advantages of the proposed ΩR method can be summarized as follows: (1) ΩR is from 0 to 1 and can be further used in statistics and correlation analysis as a physical quantity. (2) ΩR can distinguish the rotational vortices from the shear layers, discontinuity structures, and other non-physical structures. (3) ΩR is quite robust and can be always set as 0.52 to capture vortex structures in different cases and at different time steps.read more
Citations
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Journal ArticleDOI
Third generation of vortex identification methods: Omega and Liutex/Rortex based systems
Chaoqun Liu,Yisheng Gao,Xiang-rui Dong,Yiqian Wang,Jian-ming Liu,Jian-ming Liu,Yuning Zhang,Xiao-shu Cai,Nan Gui +8 more
TL;DR: Liutex/Rortex is a new physical quantity with scalar, vector and tensor forms exactly representing the local rigid rotation of fluids as mentioned in this paper, which can be considered as the second generation of vortex identification methods.
Journal ArticleDOI
Letter: Modified normalized Rortex/vortex identification method.
Jianming Liu,Chaoqun Liu +1 more
TL;DR: In this paper, a modified normalized Rortex/vortex identification method named Omega_R is presented to improve the original Omega-R method and cure the bulging phenomenon on the iso-surfaces caused by the original method.
Journal ArticleDOI
Modified normalized Rortex/vortex identification method
TL;DR: In this paper, a modified normalized Rortex/vortex identification method named ΩR is presented to improve the original Ω-R method and resolve the bulging phenomenon on the isosurfaces.
Journal ArticleDOI
A Liutex based definition and identification of vortex core center lines
TL;DR: Li et al. as discussed by the authors proposed a Liutex-based definition of vortex core center, also called vortex rotation axis line, which mathematically implies that the cross product of the L 1 magnitude gradient vector and the L 2 vector on the line is equal to zero.
Journal ArticleDOI
An objective version of the Rortex vector for vortex identification
TL;DR: In this article, an objective Rortex vortex vector is defined which uses a spatially averaged vorticity to offset the impact of the motion frame, which can be used to obtain the objectivity.
References
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On the identification of a vortex
Jinhee Jeong,Fazle Hussain +1 more
TL;DR: In this article, the authors propose a definition of vortex in an incompressible flow in terms of the eigenvalues of the symmetric tensor, which captures the pressure minimum in a plane perpendicular to the vortex axis at high Reynolds numbers, and also accurately defines vortex cores at low Reynolds numbers.
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A general classification of three-dimensional flow fields
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Journal ArticleDOI
New omega vortex identification method
TL;DR: In this paper, a new vortex identification criterion called W -method is proposed based on the ideas that vorticity overtakes deformation in vortex and W = 0.52 is a quantity to approximately define the vortex boundary.
Journal ArticleDOI
Rortex A New Vortex Vector Definition and Vorticity Tensor and Vector Decompositions
TL;DR: In this article, the existence of the rotational axis is proved through real Schur decomposition, and a fast algorithm for calculating Rortex is also presented based on the real-Schur-decomposition.
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