FIGURE 5 Time histories of Cl and
Cd for CA models with same frequency. The
flapping was set to downstroke firstly and then upstroke. Where, the
downstroke is indicated by the shaded area. (a-c) theCl of AP1 is always the highest at the three
flapping frequencies. (d-f) the Cd of the AP1 is
the highest at the low-frequency flapping (55 Hz). With the increase of
the flapping frequency, the Cd of the AP1 begin
to fall.
Table 2 The average Cl(l ), average Cd (l ) and averageCl/Cd(\(\overset{\overline{}}{C_{l}/C_{d}}\))
of CA models at different flapping
frequencies