All,
We are seeing large differences in analyses of the same railcar using 1) body loads and 2) loads on nodes. We are using all plate elements (CQUAD4), and we are using symmetry.
Our first set of analyses are with body loads, with amplified translational accelerations to produce the correct support reactions. Calculated stresses after linear static runs are, for example 50 MPa. Deflections approximately 3.5mm.
The same model is re-run, this time with no body loads, but loads on nodes of primary structural members. Reactions are very similar to those calculated above, but calculated stress is about 100 MPa, and deflections 5.5 mm.
Any ideas?
tg
We are seeing large differences in analyses of the same railcar using 1) body loads and 2) loads on nodes. We are using all plate elements (CQUAD4), and we are using symmetry.
Our first set of analyses are with body loads, with amplified translational accelerations to produce the correct support reactions. Calculated stresses after linear static runs are, for example 50 MPa. Deflections approximately 3.5mm.
The same model is re-run, this time with no body loads, but loads on nodes of primary structural members. Reactions are very similar to those calculated above, but calculated stress is about 100 MPa, and deflections 5.5 mm.
Any ideas?
tg
