Hello Blas,
of course when factors are set to zero, I get correct Euler-Bernoulli beam results. Again, when I leave them to default values, natural frequency results are larger than Timoshenko theory, obviously missing rotational inertia. I guess Nastran authors reference Timoshenko method, but...
Hello Blas,
Problem is I do use beam elements, as mentioned in question. And it's 1D model (only vertical vibrations). And yet the results are not satisfying.
It's really fishy Nastran results are same as shear model and not Timoshenko like Ansys. And yes, model is made in Femap with choosing...
I've analyticaly solved natural frequencies of a beam with shear model, and then Timoshenko model (that includes rotational inertia).
I've then solved the same beam in Nastran using Lanczos method and coupled mass. Results are following shear model that doesn't include rotational inertia. Ansys...
