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Figure 11 - Velocity pattern and turbulent kinetic energy k distribution in the electrolyte
layer for the case with selective collector rodding


Figure 12 - Velocity pattern and turbulent kinetic energy k distribution in the aluminium
layer for the case with selective collector rodding

The metal pad surface oscillation still exists, however not growing after a rather long
time period simulated (Figure 15) , because the magnetic field B
z
component for the end
cells is about 14 Gs on average if compared to 8 Gs for the cells in mid-line where a high
level of MHD stability is achieved (see Figure 16). The cell voltage oscillations shown
additionally in Figures 9 and 15 indicate similar oscillations, which can be easily detectable
from the overall cell voltage measurements. The average voltage is decreasing in magnitude
by 1-2 mV during the course of the simulation in both cases because of the gradual anode
burnout process incorporated in the model which makes the average ACD more uniform,
reduces the overall cell resistivity and stabilizes the cell noise produced by the MHD waves.