Figure 5: Flow structures at different rotation ratios.
From: Multiple states in highly turbulent Taylor–Couette flow
Azimuthal velocity as a function of height z/L for various a. Subset of the data shown in Fig. 3c,d. (a) Profiles following trajectory V. (b) Profiles following trajectory I. For aε{0.00,0.15,0.55,0.75} the velocity profiles are the same for both trajectories. For intermediate values (aε{0.20,0.35,0.40}) the profiles are different; trajectory V (red) shows the emergence of four rolls in the top half of the system, while trajectory I (blue) shows only three rolls in the top half of the system. For the case of maximum torque (a=0.35), dashed lines are drawn to indicate the boundaries between the rolls. For a=0.15 the system shows the high state (with four rolls in the top half). This structure seems to fade once the system is pushed towards a=0, see also Fig. 3c,d. On the right we show a schematical overview of the rolls and the angular velocity profile for a=0.35 in 3D, τ=0.2 s.
