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10 CM METAL PAD CASE

In order to test the versatility of MHD-Valdis metal pad current density field
solver, two additional configurations, in addition to the base case presented above, are
being presented. In the first variation case, the metal pad thickness is reduced from 20 cm
down to 10 cm. The resulting metal pad current density field solutions for the 3D
ANSYSŪ model, the partial 1D ANSYSŪ model and the MHD-Valdis model are
presented respectively in Figures 7, 8 and 9.

Reducing by half the height of the metal pad simply doubles the intensity of the
horizontal component of the current density field. As expected, all the three models are
correctly making that prediction. As we will see below, increasing the intensity of the
horizontal component of the metal pad current density field has a significant impact on
the MHD cell stability.

Figure 7: Full cell 3D model metal pad current density field solution