Electroviscous Effects in Stationary Solid Phase Suspensions
Round 1
Reviewer 1 Report
Comments on fluids-1098720 Electroviscous effects in stationary solid
phase suspensions by Rubio-Hernandez
This manuscript offers a review of suspension mechanics, and
electostatic and electrokinetic effects, leading eventually to the
electroviscous effect, an increase in the apparent viscosity of liquid
flowing through the pore space between charged solids due to the
development of an electrical field tending to oppose the flow.
The manuscript covers a great deal of ground in a relatively small
number of pages, so I think will be useful to readers wanting to get
an update on this field.
I recommend publication after minor correction.
abstract: ``overfull electroviscous effect'' -- I'm not sure what ``overfull''
means in this context; is ``overfull'' the correct word?
page 3: you mean Mooney, not Money
page 6: it would be useful if some physical details of how equation
(16) is obtained could be sketched out (in words, without extra
equations); is it just a matter of matching a pressure-driven porous
medium Darcy flow to an electrophoretic flow (or is there more to it
than that?); is there a relationship with the non-equilibrium
thermodynamics to be presented later on page 9?
page 6: does ``specific conductivity'' in this context refer to the
electrical conductivity or the hydraulic conductivity?
page 9: I think there is a typo in (21) and (22) -- you want the left
hand side of (21) to be Q (volumetric flux) and the left hand side of
(22) to be J (electric currently flux), so that the right hand side of
(23) can be Q/DeltaP in the uncharged case, which then matches (24),
which is a classical result for uncharged Poiseuille flow. In the
case *with* electrical charge here, don't you need some information
about the electrical current (e.g. zero net current) to establish a
relation between DeltaP and Deltaphi, and then you can eliminate
Deltaphi from the system of equations, to write a proportionality
between Q and DeltaP, with an expression for L_11 having the same
general form as (24), but now with an apparent viscosity replacing the
true viscosity to account for electrical effects? Is that how the
analysis would proceed?
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The purpose of this review is to briefly and concisely presents the state of the art on theoretical and experimental results relative to the electroviscous effect observed in suspensions when the liquid phase moves with respect to the stationary solid phase.
Interesting works.
Some suggestions:
- Using a cell model, according to which the radius of influence of a particle is higher than its solid radius. this sentence is misleading.
- in section 2, it is about hard-particles suspensions. from this part, i want to consult, it looks like nanofluids?
- the recent review may be helpful: A brief review of the correlation between electrical properties and wetting behaviour in porous media.
- Above the equation 16, refers now to the radius of the porous, plug may be added after porous. In addition, i do not find the symbal a in equation 16.
- I think equation 24 may be Hagen−Poiseuille law
- A section discussion and further work may be added.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
