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<strong>of</strong> phase. Figure 6-10 B) and D) are individual Lissajous figures taken at 88% span vs. 69%<br />

ch<strong>or</strong>d location, which also c<strong>or</strong>responds to shock recovery region as seen in Figure 6-6 C).<br />

Similarly, another odd figure-eight-like shape due to the continuous phase variation is seen. The<br />

3-D plot in D) is similar to that in C), with the loop feature happening later in the cycle.<br />

Wavelet Analysis<br />

Wavelet analysis is applied to points <strong>of</strong> interest on the wing in Figure 6-11 and Figure 6-<br />

12, f<strong>or</strong> the Grid0 8Hz roll case in <strong>or</strong>der to gain further insight into the temp<strong>or</strong>al nature <strong>of</strong> the<br />

results. In each set <strong>of</strong> figures, A) gives the time hist<strong>or</strong>y <strong>of</strong> the Cp variation, B) shows the fast<br />

Fourier transf<strong>or</strong>m (FFT) <strong>of</strong> the data, and C) illustrates the wavelet transf<strong>or</strong>m view <strong>of</strong> frequency<br />

vs. time. Figure 6-11 contains the results at 93% span vs. 65% ch<strong>or</strong>d and Figure 6-12 is at 88%<br />

span vs. 69% ch<strong>or</strong>d. Both <strong>of</strong> these locations c<strong>or</strong>respond to the shock recovery regions as<br />

previously mentioned.<br />

From both figures, the time hist<strong>or</strong>y plots in A) reveal a fairly sinusoidal response in upper<br />

wing surface Cp. The FFT plots in B) both show a prominent peak at the input frequency <strong>of</strong> 8Hz<br />

and smaller peaks at the harmonics. The wavelet plots in C) are also very similar and reveal most<br />

<strong>of</strong> the energy concentration occurring at 8Hz as expected, with the higher frequency harmonics<br />

participating on the upstroke and downstroke <strong>of</strong> the oscillation. The wavelet analysis confirms a<br />

periodic response as predicted by the FFT.<br />

Flow Visualization<br />

Tip-Launcher Roll Oscillations<br />

In <strong>or</strong>der to emulate the bending nature <strong>of</strong> an LCO mechanism, the FSR flow-field break-<br />

down is extended by perf<strong>or</strong>ming a f<strong>or</strong>ced, rigid-body roll oscillation f<strong>or</strong> a m<strong>or</strong>e refined F-16<br />

Grid4 with tip launchers, LE edge antennae, and gun p<strong>or</strong>t. An 8Hz ±0.5° rigid-body roll<br />

77

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