scholarly journals Large axisymmetric surface deformation and dewetting in the flow above a rotating disk in a cylindrical tank: Spin-up and permanent regimes

2020 ◽  
Vol 5 (4) ◽  
Author(s):  
Wen Yang ◽  
Ivan Delbende ◽  
Yann Fraigneau ◽  
Laurent Martin Witkowski
Keyword(s):  
Surface Deformation ◽  
Rotating Disk ◽  
Cylindrical Tank ◽  
Axisymmetric Surface

Axisymmetric rotating flow with free surface in a cylindrical tank

2018 ◽  
Vol 861 ◽  
pp. 796-814 ◽  
Author(s):  
Wen Yang ◽  
Ivan Delbende ◽  
Yann Fraigneau ◽  
Laurent Martin Witkowski
Keyword(s):  
Reynolds Number ◽  
Free Surface ◽  
Surface Deformation ◽  
Fluid Layer ◽  
Three Dimensional ◽  
Azimuthal Velocity ◽  
Meridional Plane ◽  
Cylindrical Tank ◽  
Aspect Ratios ◽  
Steady Solutions

The flow induced by a disk rotating at the bottom of a cylindrical tank is characterised using numerical techniques – computation of steady solutions or time-averaged two-dimensional and three-dimensional direct simulations – as well as laser-Doppler velocimetry measurements. Axisymmetric steady solutions reveal the structure of the toroidal flow located at the periphery of the central solid body rotation region. When viewed in a meridional plane, this flow cell is found to be bordered by four layers, two at the solid boundaries, one at the free surface and one located at the edge of the central region, which possesses a sinuous shape. The cell intensity and geometry are determined for several fluid-layer aspect ratios; the flow is shown to depend very weakly on Froude number (associated with surface deformation) or on Reynolds number if sufficiently large. The paper then focuses on the high Reynolds number regime for which the flow has become unsteady and three-dimensional while the surface is still almost flat. Direct numerical simulations show that the averaged flow shares many similarities with the above steady axisymmetric solutions. Experimental measurements corroborate most of the numerical results and also allow for the spatio-temporal characterisation of the fluctuations, in particular the azimuthal structure and frequency spectrum. Mean azimuthal velocity profiles obtained in this transitional regime are eventually compared to existing theoretical models.

Entrainment and mixing dynamics of surface-stress-driven stratified flow in a cylinder

2012 ◽  
Vol 691 ◽  
pp. 498-517 ◽  
Author(s):  
A. Shravat ◽  
C. Cenedese ◽  
C. P. Caulfield
Keyword(s):  
Surface Stress ◽  
High Frequency ◽  
Rotating Disk ◽  
Disk Drive ◽  
Time Dependent ◽  
Characteristic Velocity ◽  
Cylindrical Tank ◽  
Rate Of Increase ◽  
Mixing Dynamics ◽  
Probe Measurements

AbstractWe extend previous work of Boyer, Davies & Guo (Fluid Dyn. Res., vol. 21, 1997, pp. 381–401) to consider the evolution of an initially two-layer stratified fluid in a cylindrical tank which is driven by a horizontal rotating disk. The turbulent motions induced by the disk drive entrainment at the interface, and similarly to the results of Boyeret al. (1997), the layer nearer to the disk deepens. Through high-frequency conductivity probe measurements, we establish that the deepening layer is very well-mixed, and the thickness of the interface between the two evolving layers appears to be approximately constant. Under certain circumstances, we find that the rate of increase in depth of the deepening layer decreases with time, at variance with the results of Boyeret al. (1997), and implying that the characteristic velocity in the deepening layer decreases as the upper layer deepens. We propose that such time-dependent deepening, and the associated weakening of the upper-layer velocities, occurs naturally because of the combined power requirements of entrainment and layer homogenization which inhibit, when the stratification is very strong, the characteristic velocities of the deepening layer approaching the (constant) velocities of the driving disk, as assumed by Boyeret al. (1997).

A Sectional Model for Investigating Microcontamination in a Rotating Disk CVD Reactor

2004 ◽  
Vol 38 (12) ◽  
pp. 1161-1170 ◽  
Author(s):  
Z. Sun ◽  
R. L. Axelbaum ◽  
R. W. Davis
Keyword(s):  
Rotating Disk ◽  
Sectional Model

Fabrication and Characterization of Nife Thin Film Composition Modulated Alloys

1996 ◽  
Vol 451 ◽  
Author(s):  
S. D. Leith ◽  
D. T. Schwartz
Keyword(s):  
Rotation Rate ◽  
Stripping Voltammetry ◽  
Rotating Disk ◽  
Oscillation Period ◽  
Rotating Disk Electrode ◽  
Disk Rotation ◽  
Rate Oscillation ◽  
Composition And Structure ◽  
Spatially Periodic

ABSTRACTDescribed are results showing that an oscillating flow-field can induce spatially periodic composition variations in electrodeposited NiFe films. Flow-induced NiFe composition modulated alloys (CMA's) were deposited on the disk of a rotating disk electrode by oscillating the disk rotation rate during galvanostatic plating. Deposit composition and structure were investigated using potentiostatic stripping voltammetry and scanning probe microscopy. Results illustrate a linear relationship between the composition modulation wavelength and the flow oscillation period. CMA's with wavelengths less than 10 nm can be fabricated when plating with a disk rotation rate oscillation period less than 3 seconds.

An Optoelectronic System for Real-Time Surface Deformation Measurements

Vestnik MEI ◽  
2019 ◽  
Vol 2 (2) ◽  
pp. 101-108
Author(s):  
Anton Yu. Poroykov ◽  
◽  
Konstantin M. Lapitskiy ◽  
Keyword(s):  
Real Time ◽  
Surface Deformation ◽  
Optoelectronic System ◽  
Deformation Measurements
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