Damped Oscillations in the Viscosity of Suspensions of Rigid Rods. II. Bimodal and Polydisperse Suspensions

The transient non‐Newtonian viscosity of suspensions with a (slightly polydisperse) bimodal particle size distribution and of rather highly polydisperse suspensions has been studied. For bimodal systems the dominant frequencies can be determined from the frequency spectra of the oscillations. They correspond to the rotational frequencies of the two species constituting the bimodal suspension. For polydisperse suspensions, the damping in viscosity is very rapid and the dominant frequency is shifted toward values corresponding to the period of rotation of the larger particles present.