Vortex Flows with Particles and Droplets (A Review)

Abstract

Single-phase vortices are a classic example of objects characterized by symmetry in the distribution of all main parameters. The presence of inertial particles (or droplets) in such objects, even with their initial uniform distribution in space, leads to symmetry breaking due to the inverse effect of the dispersed phase on the characteristics of carrier vortices. A review of calculation-theoretical and experimental works devoted to the study of the motion of particles (or droplets) in various concentrated vortex structures, as well as their inverse effect on vortex characteristics, is conducted. The main characteristics (inertia, concentration) as well as dimensionless parameters (Reynolds, Stokes, Froude, Tachikawa numbers) determining the interaction between the dispersed phase and vortices are described. The results of available studies are analyzed in order to establish the peculiarities of particle (or droplet) behavior and stability of different vortex structures, including natural ones. The works analyzed in the review cover a wide range of inertia of the dispersed phase (Stkf = 0.002 − 14.7) and vortex intensities (ReΓ = 200 − 5000).

Simulation of Parameters of Plasma Dynamics of a Magneto Plasma Compressor

“…The goal of this research is the development of a mathematical model as well suited as possible to the experimental conditions and the systematic numerical study of discharges in gases for a wide range of variation in basic parameters of the magneto plasma compressor and the ambient gas environment based on this model. The plasma formation processes of a magneto plasma compressor discharge in gas are generally three dimensional and some fluctuations are caused both by spatial and temporal inhomogeneity [15][16][17][18][19][20][21][22][23][24][25]. The full model is presented in the literature [12,14,19].…”

Mathematical Modeling of Structure and Dynamics of Concentrated Tornado-like Vortices: A Review

“…The fourth reason is the reverse effect of the dispersed phase on the behavior of the vortex structure. There are numerous works showing that, at certain concentrations, the dispersed phase can have a significant effect on the characteristics of an atmospheric vortex and its behavior (up to decay) [87][88][89][90]. The second reason is that the possibility of measuring the velocity of the dispersed phase opens the way to studying the dynamics of the vortex structure.…”

“…The fourth reason is the reverse effect of the dispersed phase on the behavior of the vortex structure. There are numerous works showing that, at certain concentrations, the dispersed phase can have a significant effect on the characteristics of an atmospheric vortex and its behavior (up to decay) [87][88][89][90].…”

A Study and Optimization of the Unsteady Flow Characteristics in the Last Stage Impeller of a Small-Scale Multi-Stage Hydraulic Turbine

“…Cavitation is a unique physical property of liquid due to local pressure drops to saturated vapor pressure; the continuity of water is destroyed to form bubbles, which includes inception, growth, contraction, and ultimate collapse [6,7]. Cavitation in a hydraulic turbine involves a transition from single-phase liquid flow to vapor-liquid mixed two-phase flow.…”

“…6 Middle guide vane 0.73 × 106 1.10 × 10 6 1.75× 10 6 2.23 × 10 6 Second-stage guide vane 0.54 × 10 6 0.80 × 10 6 1.04 × 10 6 1.50 × 10 6…”