I want to make a thermal expansion simulation of a SC8R shell, but i find the thickness of the shell changed before deformation, it should be 0.6mm, but in the odb file, it is 0.60009765mm. So i don't give the temperature load, the thickness is the same 0.60009765mm, so i search the coorfinate of 2 nodes, in assembly, one z coordinate is 3037.125504mm, the other is 3036.525504mm, so the distance is 0.6mm. But in the odb file, one z coordinate is 3037.12548828125, the other is 3036.525390625, the distance is 0.60009765mm. i didn't give any load, but the coordinates of the nodes changed. What is the problem? Thanks for your sincere advice