Figure 1

Upper row. Fluorescing fibers can be seen throughout the thickness of the gap: $x\mathrm{\text{−}}z$ images of the suspension (a) before and (b) after a run at $\gamma =2.60$ with $c=0.15$. (c) Top view of the gap. Bottom row. Left: Experimental setup: the shaded orange area shows the $1{\mathrm{cm}}^2$ region that is imaged in the $x\mathrm{\text{−}}z$ plane. Right: $x\mathrm{\text{−}}y\mathrm{\text{−}}z$ coordinate system, chosen to correspond to the flow, velocity gradient, and vorticity directions, respectively. Three Jeffery orbits are shown in different colors, with the corresponding rod shown in green only for the red orbit. The angles $\theta$ and $\varphi$ are the polar and azimuthal angles, respectively, of the rod. The orientation of the fiber projected onto the $x\mathrm{\text{−}}z$ plane is $\alpha$, as shown.Reuse & Permissions

Figure 2

Rheological data showing decay of activity as measured by ${\eta }^{\prime \prime }$ for different strain amplitudes, as indicated in the legend.Reuse & Permissions

Figure 3

Temporal evolution of the average orientation in the $x\mathrm{\text{−}}z$ plane for different strain amplitudes, as indicated in the legend. Inset: Change in orientation $\Delta S_{\alpha }=S_{\alpha }(\infty )-S_{\alpha }(0)$.Reuse & Permissions

Figure 4

Left: Schematic of a Jeffery orbit and its projection (cross section) ${\sigma }_C$ in shades of gray. Upper right: Temporal evolution of the control parameter $\Phi$ for different strains indicated in the legend. Dashed line indicates ${\Phi }_c=0.60$. Lower right: Probability distribution function of $C_b=C/(C+1)$ for selected strains.Reuse & Permissions

Figure 5

Rheological activity data rescaled using the scaling exponents $\beta =0.86$ and $\nu =1.09$, with strains indicated in the legend. Inset shows the best scaling that can be achieved when $\Phi$ is held constant, which is equivalent to using $\gamma$ as the control parameter. The curve in the inset for $\gamma =2.04$ starts on the critical line but falls off after about 6 cycles, consistent with the time at which $\Phi (t)$ falls below 0.6 (see Fig. 4 inset).Reuse & Permissions