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Six cases were modeled:

Amperage (kA)

Enhanced Cooling Measure

300

None

300

Fins

300

Forced-air

500

None

500

Fins

500

Forced-air

IMPACT OF MESH REFINEMENT

It is well known that the element size has a strong impact on the accuracy of a

finite element solution. The adequate size is however physics-dependent. In a mechanical
simulation using a non-linear constitutive law, for example plasticity, the response is
strongly dependent on the strain level, which is obtained from the displacement gradient.
Finer meshes are therefore required compared to a thermal simulation.

Figure 1 compares the vertical displacement on the long axis of the shell floor for

the initial mesh (Figure 2a) and for a refined mesh (Figure 2b) of the 300 kA cell without
cooling enhancement measures. It is quite obvious that the initial mesh was inadequate
for the mechanical analysis, as the maximum displacement is almost twice as large for
the coarser mesh.

Figure 1 Vertical displacement on the 300 kA cell shell floor on the long axis