i found that the sectional area go very high from station 41.2 to 42.2 but still do not know why ?
If you look closely at your midship you can see the color of one surface “bleeding” into the other, indicating you have two surfaces modeled on top of one another. Therefore there are two cross sections calculated on that particular location.
thanks for help
With doubled up surfaces you will also get excessive displacement … see #2172