Transient response of an electrorheological fluid under square-wave electric field excitation

Structure evolution in electrorheological fluids flowing through microchannels

“…For ER fluids undergoing steady shear, the characteristic time for the shear stress to reach steady state is proportional to shear rate and only weakly dependent on electric field strength. The shear-rate dependence of the stress response was confirmed in later experiments and an exponential increase in shear stress over time was observed 15,16 . This shearrate dependence of the stress response was ascribed to a hypothesized rate-dependence associated with column breakup and formation.…”

Comment on “Universal yield stress equation for transient response of zeolite based electrorheological fluid”

“…6 reported in Ref. [9] as a function of applied electric field strengths in a log-log scale, and obtained the E c for the each sample which resulted from the crossover of two slopes, corresponding to the polarization model (slope = 2) and conductivity model (slope = 1.5), respectively as shown in Fig. 1.…”

“…6 in Ref. [9] displayed the increase of shear stress as a function of electric field strength with a fixed shear rate.…”

“…Recently, Tian et al [9] reported ER behavior of zeolite based ER fluids, focusing on the transient response at low shear rate as their continuing works on ER characterization. Among their results, Fig.…”

“…In this comment, we reanalyzed their ER data [9] using both polarization model and conduction model of the ER mechanism, and then correlated with a universal scaling relationship between external electric field and yield stress.…”