- #1

hari123

- 8

- 0

Hi all,

I have performed a small static analysis with one element (C3D8). The bottom face of element is completely constrained, and the top part is displaced.

In the geometrical linear analysis, the internal energy (ALLIE) and the work done (ALLWK) are equal. So, with ETOTAL = ALLIE - ALLWK, the total energy was zero. But in the case of geometrical non-linear analysis, ALLIE > ALLWK and the total energy (Etotal) was increasing over the time.

How is this possible ??, the total energy has to be constant, and should be zero for the case of static analysis.

Note:

Please find the attached inp file, and the energy plots for the linear and non-linear cases.

I have performed a small static analysis with one element (C3D8). The bottom face of element is completely constrained, and the top part is displaced.

In the geometrical linear analysis, the internal energy (ALLIE) and the work done (ALLWK) are equal. So, with ETOTAL = ALLIE - ALLWK, the total energy was zero. But in the case of geometrical non-linear analysis, ALLIE > ALLWK and the total energy (Etotal) was increasing over the time.

How is this possible ??, the total energy has to be constant, and should be zero for the case of static analysis.

Note:

Please find the attached inp file, and the energy plots for the linear and non-linear cases.