A vortex is intuitively recognized as the rotational/swirling motion of the fluids. However, an
unambiguous and universally accepted definition for vortex is yet to be achieved in the field …

Most of the current Eulerian vortex identification criteria, including the Q criterion and the λ ci
criterion, are exclusively determined by the eigenvalues of the velocity gradient tensor or the …

Although the vortex is ubiquitous in nature, its definition is somewhat ambiguous in the field
of fluid dynamics. In this absence of a rigorous mathematical definition, considerable …

A new vector named Rortex [C. Liu et al.,“Rortex—A new vortex vector definition and vorticity
tensor and vector decompositions,” Phys. Fluids 30, 035103 (2018)] was proposed to …

Vortices are a ubiquitous natural phenomenon, and their structure, shape, and
characteristics should be independent of the observer, which implies that the vortex …

In the present study, the physical meaning of vorticity is revisited based on the Liutex-Shear
(RS) decomposition proposed by Liu et al. in the framework of Liutex (previously called …

A vortex is intuitively recognized as the rotational/swirling motion of fluids, but a rigorous and
universally-accepted definition is still not available. Vorticity tube/filament has been …

A new vortex identification criterion, named Ω R⁠, is proposed for the normalization of
Rortex, using the idea of the Omega method (⁠ Ω⁠). Ω R is a normalized function from 0 to …

This book is a comprehensive and intensive monograph for scientists, engineers and
applied mathematicians, as well as graduate students in fluid dynamics. It starts with a brief …

Considerable confusion surrounds the longstanding question of what constitutes a vortex,
especially in a turbulent flow. This question, frequently misunderstood as academic, has …