Steric effect and slip‐modulated energy transfer in narrow fluidic channels with finite aspect ratios

Abstract

In this study, we delineate the combined consequences of finite channel aspect ratios, wall slip effects and steric interactions on the energy transfer mechanisms in narrow fluidic confinements. By considering the details of ionic interactions within the electrical double layer, we demonstrate that considerations of finite aspect ratios and steric effects may result in dramatic alterations in the predictions of effective viscosity as well as the energy transfer efficiency, particularly for high magnitudes of the surface charge density, as compared with the predictions based on parallel plate channel considerations. We also illustrate the possibilities of obtaining very high energy transfer efficiencies by employing channels of aspect ratios close to unity, with a judicious exploitation of steric interactions and wall slippage effects in highly confined geometries.

Dielectric properties of a single nanochannel investigated by high-frequency impedance spectroscopy

“…[12], [13] Compared to the classical microfluidic field, the nanometer dimension of the channel requires specific theoretical predictions and experimental discussions. [14], [15], [16], [17]. The conductance law through nanochannels depends on the ionic strength of the background electrolyte.…”

Electroosmotic flows with simultaneous spatio-temporal modulations in zeta potential: cases of thick electrical double layers beyond the Debye Hückel limit

“…With an increasing shift of paradigm from microfluidics towards nanofluidics as assisted by the advent of more sophisticated miniaturization protocols, situations addressing thick EDL limits are turning out to be virtually inevitable in many modern-day technological practices. Accordingly, in the present work, we address the cases of thick EDL (Das and Chakraborty 2011;Chakraborty and Chakraborty 2011;Chakraborty and Chakraborty 2010;Garai and Chakraborty 2010;Goswami and Chakraborty 2010;Das and Chakraborty 2009;Talapatra and Chakraborty 2009;Das and Chakraborty 2008;Talapatra and Chakraborty 2008;Chakraborty and Srivastava 2007) limits as well, extending the early work of Conlisk (2005) and co-researchers (Conlisk and Mcferran 2002) based on uniform zeta potentials. Importantly, we do not resort to the celebrated Debye-Hückel linearization approximation Li 2005) for obtaining the potential distribution, thereby rendering our solutions applicable to situations characterized by high surface potentials as well.…”

Steric effects on electrokinetic flow of non-linear biofluids

“…Although this is right for sufficiently dilute solutions, it may result in significant errors in predicting the electrical potential field in the presence of high ionic concentration, especially at large zeta potentials. The importance of ionic size effects is determined by the mean volume fraction of the ions in the bulk, usually called the steric factor [14]. The mean volume fraction of each ion in the bulk is given by 3 0 a n   [15].…”