FIGURE 8.
The ratio of displacement of the center of gravity versus the ratio of the migration distances of forward and backward flows, lF/lB. Data from six experiments are plotted. The shifting velocity of the velocity field u, the velocity of the flow v, and the duration of the flow T are obtained from the data in Fig. 5 and the migration distance is calculated from Eq. 1. Displacement ratios are calculated from every three consecutive extrema in the projected center of gravity curve. A different symbol is used for each experiment.