Effect of structure of reinforced fiber on field distribution characteristics in ionic membrane
(2.National Key Laboratory of Fluorinated Functional Membrane Materials, Zibo, Shandong, China 256401)
(3.State Key Multi-phase Reaction Laboratory of Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China 100190)
(4.Bluestar Shenyang Research Institute of Light Industry Machinery, Shenyang, Liaoning, China 110015)
【Abstract】To investigate the influence of the structure of the reinforced fibers on field distribution in ion-exchange membrane (IEM), the matter migration processes in the IEM with the reinforced fibers in the presence of the electric field were simulated by using the percolation flow model in porous media, the transport of diluted species model and the secondary current distribution model. The convective velocity, concentration and current density in the IEM were obtained. The effects of the shape, pitch and the mode of network of the reinforced fibers on the field distribution were studied. The ion concentration on the surface of the membrane after electrolysis was measured by photography and image processing technology. The experimental results were in good agreement with the simulation results. The results show that the convective velocity at the central region encircled by the reinforced fibers is the highest. The closer to the reinforced fibers, the lower the velocity, and the greater the concentration and the current density. Higher velocity and current density can be obtained in the IEM by using the orthogonal reinforced fibers. The larger the distance between the ribs, the lower the current density, and the more uniform the distribution. The highest value and the most inhomogeneous distribution of the current density can be obtained by using the ellipse reinforced fibers with its major axis vertical to the flow.
【Keywords】 ion-exchange membrane; reinforced fiber; computational fluid dynamics; numerical simulation;
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