Fig. 7
From: Oscillatory interactions of two spheres in an unbounded couple stress fluid
Drag force versus time t for different values of velocity ratio parameters with \(a_2/a_1=2.0,U_2/U_1=0.5,\bar{\eta }=0.1,\bar{\eta }'=0.01 \delta =4.0\) for low frequency at \(\alpha =0.5\) (a) in-phase, (b) out-of-phase.
