Computational Fluid Dynamics Characterization of a Rotating Cylinder Electrochemical Reactor using an RANS-RNG Turbulence Model

R. Enciso, L. A. Padilla, C. Ojeda, J. A. Delgadillo, I. Rodríguez
Int. J. Electrochem. Sci., 7 (2012) 12181-12192, 2012.


The electrochemical reactor with a rotating cylinder electrode is typically used in processes under mass transfer control. Characterization of the flow is needed to optimize the efficiency of the reactor. Because the complexity of the geometry in 3 dimensions requires a more sophisticated approach, computational fluid dynamics (CFD) has been used to describe the fluid flow in a 3-dimensional electrochemical rotating cylinder reactor. CFD has been applied in some studies, but these studies have not addressed the effect of the counter electrode geometry. In this paper, a CFD description of an electrochemical rotating cylinder reactor with four plates as counter electrodes is presented. Four design configurations were explored, in which both the size and number of counter electrodes were varied. The rotation velocity of the cylinder electrode was held constant at 400 rpm. The software FluentTM was used to solve the governing equations, and the RNG k-ɛ model was used to describe the turbulence effect of the flow. The simulated results were validated with experimental data obtained by digital image analysis (DIA) at the surface of the reactor. The results show that the arrangement of the electrode and counter electrodes significantly modifies the stream lines of the flow, generating high-velocity zones within the tank of the reactor, particularly at the surface of the electrode and at the bottom of the reactor. Furthermore, there are some zones at the periphery of the electrodes that exhibit low-velocity stream lines. The experimental profiles are described with CFD modeling and demonstrate the validity of the models used in the simulation. Therefore, full characterization of the fluid flow of an electrochemical reactor is possible through the application of CFD.