2. Benchmark solution#

2.1. Calculation method used for reference solutions#

The reference solution is a solution obtained with Python. Indeed, two calculation methods were used to determine the frequencies. Each of the methods uses the stiffness, mass, gyroscopic, and damping matrices calculated by*Code_Aster*. To find the frequencies of the quadratic modal problem, we use:

  • the numpy python mathematical library (search for eigenvalues)

  • the CALC_MODES command

Therefore, strictly speaking, it is not a non-regression. On the other hand, for the validation of

beam elements and in the absence of elements for comparison, it is indeed a question of non-regression.

2.2. Reference quantities#

  • \(\mathrm{FREQ}\) frequency

  • \(\mathrm{AMOR}\text{\_}\mathrm{REDUIT}\): reduced amortization

2.3. Benchmark result#

As an indication, the reference results for the right Euler beam are given below.

numpy

\(N°\)

\(\mathrm{FREQ}(\mathrm{Hz})\)

\(1\)

\(123.915\)

\(2\)

\(124.546\)

\(3\)

\(497.033\)

\(4\)

\(499.575\)

CALC_MODES

\(N°\)

\(\mathrm{FREQ}(\mathrm{Hz})\)

\(\mathrm{AMOR}\text{\_}\mathrm{REDUIT}\)

\(1\)

\(123.915\)

\(0.0\)

\(20\)

\(7971.6\)

\(0.0\)

\(40\)

\(21163.265\)

\(0.0\)

\(60\)

\(37289.789\)

\(0.0\)

\(80\)

\(74712.423\)

\(0.0\)

2.4. Uncertainty about the solution#

Digital solution