Salinity Gradient Power (SGP) is potentially one of the largest sources of renewable energy on earth. Among SGP methods, Reveres Electrodialysis (RED) uses the transport of salt ions through membranes, which is then converted to electricity. A RED stack consists of a number of alternating cathode and anode exchanging permselective membranes. The spacer is usually used in unit cell to create the flow channel compartments and maintain a constant distance between the membranes. The existing structure using woven type spacer induces a lot of pressure loss at unit cell, resulting in a decrease in RED performance. Therefore, a new-type structure of unit cell is needed to reduce the pressure loss and increase RED performance.
In this study, the fluid distribution and pressure drop characteristics of unit cell in RED with different intermembrane structures were investigated numerically. The effects of the geometry of intermembrane structure were analyzed using the periodic boundary condition. The result indicated that the reduction in pressure drop was achieved in the proposed intermembrane structure as compared with the existing structure using woven type spacer.