A hydrodynamic network model for interdigitated flow fields

Comparing velocities and pressures in redox flow batteries with interdigitated and serpentine channels

“…This section examines flow distributions and pressure losses at the scale of the active area with the network model for a serpentine channel with three passes. Shyam Prasad et al describe implementation of a network model for IDFF . Figure shows dimensionless pressure, θ , as a function of distance from the inlet made dimensionless with L .…”

Modeling flow distribution and pressure drop in redox flow batteries

“…The flow resistances of the channels and the electrode are in parallel in PFF, causing the pressure drops to be the same in the two regions and the ratio of velocities to be proportional to the reciprocal of the ratio of flow resistances. The flow resistance in IDFF is a series–parallel combination of channel and electrode segments . While all electrolyte passes through the electrode in both FT and IDFF, the path is significantly shorter in IDFF.…”

“…The inlets and outlets of adjacent channels are alternately blocked in IDFF, which causes electrolyte to flow perpendicularly upward and out of an inlet channel, into the electrode, across the rib separating the channels, and finally perpendicularly out of the electrode and into an exit channel. This configuration has been studied extensively for fuel cells and to a lesser extent for flow batteries . Two consequential distinctions between these applications are: (1) simultaneously flow of liquid and gas prevails in low‐temperature fuel cells under most operating conditions while liquid flow predominates in flow batteries, and (2) IDFF forces flow through an electrochemically inactive porous layer that distributes flow evenly to a thin and relatively impermeable electrode layer in fuel cells, while flow is forced through a thick and permeable porous electrode in flow batteries.…”

Hydrodynamics and Current Distribution Analysis of Bipolar Plates for Direct Ethanol Fuel Cells

“…For example, activation losses by improving anodic and cathodic catalysts, ohmic losses by improving materials and assembly process and concentration losses by minimizing transport resistances on both parts diffusion layers and flow fields. In this way, different studies had been made about flow and pressure fields (4,(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18). The most remarkable designs are serpentine and interdigitated bipolar plate; features of last one are to force the fluid to pass through the electrode and in this way, generate a convection velocity normal to the flow field and thus improve mass transfer over the electrode by minimizing concentration losses, it means, higher values of the limit current.…”

“…The most remarkable designs are serpentine and interdigitated bipolar plate; features of last one are to force the fluid to pass through the electrode and in this way, generate a convection velocity normal to the flow field and thus improve mass transfer over the electrode by minimizing concentration losses, it means, higher values of the limit current. However, this type of plates require higher pressure drop than serpentine ones (4,12,16,17,(19)(20)(21)(22)(23). Multiple serpentine fields generate counter-flow and co-flow inside the same plate and thus uniform distribution of reacts over the electrode (4,(24)(25)(26)(27).…”