3. Modeling A#

3.1. Characteristics of modeling#

Discrete elements of stiffness, damping and mass.

_images/Object_12.svg

Characteristics of the elements:

DISCRET:

nodal mass

M_T_D_N

linear stiffness

K_T_D_L

linear amortization

A_T_D_L (\(c={c}_{\mathrm{critique}}\))

Boundary conditions: at node \(\mathit{N1}\) DDL_IMPO DX = DY = DZ = 0.

Node names: \({P}_{1}=\mathrm{N1}\), \({P}_{2}=\mathrm{N2}\).

Calculation methods:

  • Integration on a modal basis with Newmark (\(\alpha \mathrm{=}\mathrm{0,25}\), \(\delta \mathrm{=}\mathrm{0,5}\))

No time \(\Delta t\mathrm{=}{10}^{\mathrm{-}3}s\)

  • Integration on a modal basis with Euler

No time \(\Delta t\mathrm{=}{10}^{\mathrm{-}3}s\)

Observation time: \(\mathrm{0,5}s\).

3.2. Characteristics of the mesh#

Number of knots: 2

Number of meshes and type: 1 mesh SEG2

3.3. Tested sizes and results#

  • Moving point B

Move

Move

Move

Time

Reference

NEWMARK

Tolerance

EULER

Tolerance

(\(s\))

(\(m\))

Aster (\(m\))

(%)

Aster (\(m\))

(%)

0.06

1.189014 E—4

1.18886 E—4

1.18886 E—4

1.18886 E—4

0.5%

0.12

—9.42819 E—5

—9.42574 E—5

0.5%

—9.47822 E—5

0.6%

0.19

9.97958 E—5

9.97765 E—5

0.5%

9.96206 E—5

0.5%

0.25

—9.97748 E—5

—9.97526 E—5

0.5%

—9.99152 E—5

0.5%

0.31

9.78457 E—5

9.78210 E—5

9.78210 E—5

0.5%

9.83436 E—5

0.6%

0.38

—9.88705 E—5

—9.88530 E—5

0.5%

—9.84730 E—5

0.5%

0.44

9.99961 E—5

9.99754 E—5

0.5%

9.99525 E—5

0.5%

  • Point B speed

3.4. notes#

The results are tested at the peak level for the selected observation grain (10-2 s) where the values are the most significant.

The regime becomes almost permanent after the first period; this is what must be observed when conducting a transitory analysis.