Figure 4
Optimal active frequency (\(\omega ^*\)) and the corresponding maximum flow rate as a function of the free speed (\(v_f\), linear, red, top x-axis) and the stiffness coefficient (\(k_n\), logarithmic, blue, bottom x-axis). When \(k_n\) is varied, the value of the free velocity is fixed at \(v_f=3.3\). When \(v_f\) is varied, the value of \(k_n\) is fixed at \(k_n=500\). A: Optimal frequencies that maximize the flow rate. The simulated data for varying \(k_n\) are fitted with the proposed relation \(\omega ^*=k_n^{\gamma }\), with \(\gamma =0.6\pm 0.1\) (blue, solid line) and with \(\omega ^*=~1.2~\sqrt{k_n}\) (black, dashed line). See Supplementary Information for details on the error bar estimates. B: Maximum flow rate corresponding to each point of \(\omega ^*\) from Panel A.
