Numerical investigation of the current transition regimes in nanochannels
Abstract
The concentration polarization phenomena and its effects represent one of the main challenges for the optimal operation of many nanofluidic systems. A numerical investigation of the different electric current transition regimes observed during the concentration polarization phenomena in nanochannels is performed. This included a 2D‐axisymmetric simulation of the nanofluidic system (reservoir‐nanochannel‐reservoir). From these simulations, a novel mechanism is discovered that explains that different current transition regimes. This driving mechanism involves the applied electric field penetration while the convective flow mechanism is found to be negligible. This differs with the classical statement that the mixing process with less depleted areas initiated by an electrokinetic vortex instability starts the overlimiting regime. Additionally, the numerical approach allows us to identify new characteristics of the linear‐limiting transition such as source‐like and saddle‐like points of the electric field streamlines. The three voltage–current regimes (linear, limiting and overlimiting) are explained by observing and quantifying changes in electric field, potential, ion concentration and ion concentration gradients within the system.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 13, 2018
- Source ID
- 10.1002/elps.201800362
Entities
People
- Arturo Villegas
- David Berardi
- Francisco Javier Diez
Organizations
- Office of Naval Research
- Rutgers University