Fluid mechanics rotating disk

Unvulcanized Latex and Latex Compounds. A prime consideration has to be the fluid-state stabihty of the raw latex concentrate and hquid compound made from it. For many years, the mechanical stabihty of latex has been the fundamental test of this aspect. In testing, the raw latex mbber content is adjusted to 55% and an 80 g sample placed in the test vessel. The sample is then mechanically stirred at ultrahigh speed (ca 14,000 rpm) by a rotating disk, causing shear and particle cohision. The time taken to cause creation of mbber particle agglomerates is measured, and expressed as the mechanical stabihty time (MST). 

An alternative to the rotating disk method in a quiescent fluid is a stationary disk placed in a rotating fluid. This method, like the rotating disk, is based on fluid mechanics principles and has been studied using benzoic acid dissolving into water [30], Khoury et al. [31] applied the stationary disk method to the study of the mass transport of steroids into dilute polymer solutions. Since this method assumes that the rotating fluid near the disk obeys solid body rotation, the stirring device and the distance of the stirrer from the disk become important considerations when it is used. A similar device was developed by Braun and Parrott [32], who used stationary spherical tablets in a stirred liquid to study the effect of various parameters on the mass transport of benzoic acid. 

M.E. Coltrin, RJ. Kee, and G. H. Evans. A Mathematical Model of the Fluid Mechanics and Gas-Phase Chemistry in a Rotating Disk Chemical Vapor Deposition Reactor. J. Electrochem. Soc., 136(3) 819-829,1989. 

In HDI, the head flies above the disk surface with the fluid mechanics of air bearing generated by the rotation of disks at high speeds. Contact between the head and the disk occurs during the cycles of the operation start/stop and intermittently during disk operation due to the fluctuation of the fly height. Since the fly height has been reduced to —6.5 nm, the head can even interact with the disk surface via van der... 

Mechanical cell disruption techniques are based on high shear effects as fluid is forced through a narrow orifice, or a chamber containing rotating disks and glass beads to break up the cellular material. Both techniques enable some control over the extent of cell disruption. 

Coltrin ME, Kee RJ, Evans GH A mathematical-model of the fluid-mechanics and gas-phase chemistry in a rotating-disk chemical vapor-deposition reactor, J Electrochem Soc 136 819-829, 1989. 

The main objective of this chapter is to show that transport processes can significantly contribute to the electrochemical kinetics measurements and therefore should be taken into account. Transport processes are based on hydrodynamics (fluid mechanics), which is described with mathematics of the vector analysis. Students should know what the terms vector, gradient, and divergence represent. Solutions of Pick s second law of diffnsion are given as examples of hydrodynamics coupled with electrochemical kinetics. The theory and use of the rotating disk electrode (RDE) are explained. Introdnction to cyclic voltammetry (CV) techniques is also given. 

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