Strange eigenmodes

Figure 2.21 Development of the strange eigenmode in the sinusoidal shear flow (Eq. (2.66)) with random phase and a = 0.6. Time increases from left to right and top to bottom. Since the amplitude of the concentration fluctuations decreases in time the grayscale has been rescaled for each snapshot to cover the range between minimum and maximum concentrations.

W. Liu and G. Haller. Strange eigenmodes and decay of variance in the mixing of diffusive tracers. Physica D, 188 1-39, 2004. 

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