As it is known that volumetric strain is (LE11+LE22+LE33).

I followed the following steps:

1.) Extract LE11 for whole model and average it

2.) Extract LE22 for whole model and average it

3.) Extract LE33 for whole model and average it.

4.) Finally sum of (LE11+LE22+LE33).

5.)Extract U3 for specified set

6.) Combine U3 and (LE11+LE22+LE33).

Is it correct way for plotting. Can anyone guide me? Thanks in advance.