Linking separation sharpness with the characteristics of axial velocity wave zone in a hydrocyclone

In this paper the investigation of the axisymmetric flow of a liquid with a boundary perpendicular to the flow is considered. Analytical equations are derived for the radial and axial velocity and pressure components of fluid flow in a pipe of finite length with a movable right boundary, and boundary conditions on the moving boundary are also defined. A numerical solution of the problem on a finite-difference grid by the iterative Newton-Raphson method for various velocities of the boundary motion is obtained.

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Stability of a Viscous Liquid Jet in a Coaxial Twisting Compressible Airflow

Processes ◽

10.3390/pr9060918 ◽

2021 ◽

Vol 9 (6) ◽

pp. 918

Author(s):

Li-Mei Guo ◽

Ming Lü ◽

Zhi Ning

Keyword(s):

Viscous Liquid ◽

Axial Velocity ◽

Liquid Velocity ◽

Velocity Ratio ◽

Dominant Mode ◽

Liquid Jet ◽

Axisymmetric Mode ◽

Jet Instability ◽

Jet Stability ◽

Jet Breakup

Based on the linear stability analysis, a mathematical model for the stability of a viscous liquid jet in a coaxial twisting compressible airflow has been developed. It takes into account the twist and compressibility of the surrounding airflow, the viscosity of the liquid jet, and the cavitation bubbles within the liquid jet. Then, the effects of aerodynamics caused by the gas–liquid velocity difference on the jet stability are analyzed. The results show that under the airflow ejecting effect, the jet instability decreases first and then increases with the increase of the airflow axial velocity. When the gas–liquid velocity ratio A = 1, the jet is the most stable. When the gas–liquid velocity ratio A > 2, this is meaningful for the jet breakup compared with A = 0 (no air axial velocity). When the surrounding airflow swirls, the airflow rotation strength E will change the jet dominant mode. E has a stabilizing effect on the liquid jet under the axisymmetric mode, while E is conducive to jet instability under the asymmetry mode. The maximum disturbance growth rate of the liquid jet also decreases first and then increases with the increase of E. The liquid jet is the most stable when E = 0.65, and the jet starts to become more easier to breakup when E = 0.8425 compared with E = 0 (no swirling air). When the surrounding airflow twists (air moves in both axial and circumferential directions), given the axial velocity to change the circumferential velocity of the surrounding airflow, it is not conducive to the jet breakup, regardless of the axisymmetric disturbance or asymmetry disturbance.

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Improved color Doppler for cerebral blood flow axial velocity imaging

IEEE Transactions on Medical Imaging ◽

10.1109/tmi.2020.3036468 ◽

2020 ◽

pp. 1-1

Author(s):

Jianbo Tang ◽

Kivilcim Kilic ◽

Thomas L. Szabo ◽

David A. Boas

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Axial Velocity ◽

Color Doppler ◽

Velocity Imaging

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The Flow of an Incompressible Fluid through an Axial Turbo-Machine with any Number of Rows

Aeronautical Quarterly ◽

10.1017/s0001925900000585 ◽

1951 ◽

Vol 3 (2) ◽

pp. 133-144 ◽

Cited By ~ 3

Author(s):

J. W. Railly

Keyword(s):

Aspect Ratio ◽

Incompressible Fluid ◽

Radial Velocity ◽

Simple Form ◽

High Aspect Ratio ◽

Unknown Function ◽

Axial Velocity ◽

Velocity Fields ◽

Single Row ◽

Undetermined Constant

SummaryA method is described whereby, at any point in an infinite parallel annulus, the approximate axial velocity due to a single row of high aspect ratio blades may be calculated from a knowledge of the conditions of flow adjacent to the blades. The method is based on the assumption of a simplified expression for the radial velocity, being the product of an unknown function of the radius and an exponential term independent of the radius containing an undetermined constant; the function and the undetermined constant are calculated by reference to the conditions of flow in the plane of the row considered. The flow due to any number of rows is then obtained by summing the radial velocity fields due to each row and obtaining the axial velocities by integration of the equation of continuity.The solution of the problem with infinitely many rows is shown to have a simple form by virtue of the fact that the flow (provided that the velocities remain finite) settles down to a pattern which is periodic by one stage pitch.

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Vibratory Feeding by Nonsinusoidal Vibration—Optimum Wave Form

Journal of Vibration and Acoustics ◽

10.1115/1.3269243 ◽

1985 ◽

Vol 107 (2) ◽

pp. 188-195 ◽

Cited By ~ 20

Author(s):

S. Okabe ◽

Y. Kamiya ◽

K. Tsujikado ◽

Y. Yokoyama

Keyword(s):

Experimental Results ◽

Wave Form ◽

Velocity Wave ◽

The Mean ◽

Straight Lines ◽

Vibratory Conveyor ◽

Theoretical Results ◽

Vibratory Feeding

This paper presents the conveying velocity on a vibratory conveyor whose track is vibrated by nonsinusoidal vibration. The velocity wave form of the vibrating track is approximated by six straight lines, and five distortion factors of the wave form are defined. Considering the modes of motion of the particle, the mean conveying velocity is calculated for various conditions. Referring to these results, the optimum wave form is clarified analytically. The theoretical results show that the mean conveying velocity is considerably larger than that of ordinary feeders if the proper conveying conditions are chosen. The theoretical results are confirmed by experimental results.

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