Possible fix for non-converging NumCalc simulations

In most cases a bad mesh is the cause for non-converging NumCalc simulations. In some cases, however, this can also be caused by the clustering algorithm. If this is the case,, changing the settings

```
2. Main Parameters II
0 0 0 0.0000e+00 0 0 0
```

in the NC.inp file to

```
2. Main Parameters II
0 0 0 0.05 0 0 0
```

might solve the problem.