Comparison between CFD calculations of the flow in a rotating disk cell and the Cochran/Levich equations

Determination of flow patterns in a rotating disk electrode configuration by MRI

“…The most striking feature is that for the low rotation speed a great asymmetry in the flow is observed, while as the rotation speed increases a more symmetrical pattern is obtained. Figure 5 also shows how the fluid behaves in the recirculation area surrounding the rotating electrode [14]. In order to obtain a good representation of the lower velocities in the cell, the FOF was set to 45 mm/s.…”

“…This question has been mainly addressed using computational fluid dynamic (CFD) models. Two main CFD models can be used, two-dimensional models which are characterized with axisymmetric representation [10,11]and three-dimensional models [12][13][14] where a representation of the whole cell is performed [15]. In these works, authors compare their results with the fluid flow pattern calculated with analytical expressions obtained by Cochran [10,11] and focus their attention in establish which factors cause the asymmetry in flow patterns [12,13].…”

“…In these works, authors compare their results with the fluid flow pattern calculated with analytical expressions obtained by Cochran [10,11] and focus their attention in establish which factors cause the asymmetry in flow patterns [12,13]. Recently, Alexiadis et al [14]showed that even though the Cochran equation does not describe correctly the velocity profiles over the whole cell, it provides an accurate representation of the flow near the electrode, thus the Levich equation can still be employed for electrochemical analysis, where the concentrations gradients due to electrochemical reactions are typically contained. Gonzalez et al [12] addressed the problem of flow determination near the rotating rod containing the electrode for different configurations using 3D CFD and experimental optical methods.…”

Influence of Geometry and Velocity of Rotating Solids on Hydrodynamics of a Confined Volume

“…The volume fraction equation (see (1)) was solved by using the explicit time formulation. Initial conditions were defined based on measurements from the physical experiment.…”

“…A system with a rotating solid in a confined volume is common in several industrial processes, like mixing, electrochemistry, and others [1][2][3][4][5][6][7]. The hydrodynamics in the confined volume of this kind of systems present a highly turbulent flow.…”