3. Operands

3.1. Operand BASE_MODALE

♦ BASE_MODALE = Bamo

Name of the modal base of the sector built by DEFI_BASE_MODALE [U4.64.02].

3.2. Operand NB_MODE

◊ NB_MODE = nbmo

Number of modes specific to the sector to be used for cyclical calculation. By default, if the keyword does not appear, all the modes specific to the modal base are used.

3.3. Operand NB_SECTEUR

♦ NB_SECTEUR = nbsec

Number of basic sectors required to build the overall structure.

3.4. Keyword LIAISON

♦ LIAISON

Keyword factor for the definition of links between sectors.

3.4.1. Operands DROITE/GAUCHE/AXE

See [Figure 3.6-a].

Name of the right sector interface.

Name of the left sector interface.

Name of the sector axis interface.

These are common points in all sectors.

3.5. Keyword CALCUL

♦ CALCUL

Keyword factor to define how to search for specific modes.

3.5.1. Operands TOUT_DIAM/NB_DIAM

The modes associated with all the numbers of nodal diameters will be calculated.

List of numbers of nodal diameters to be calculated. By default, all possible numbers of nodal diameters are studied.

3.5.2. Operand OPTION

“PLUS_PETITE”:	calculate by a reverse iteration method the natural modes corresponding to the smallest frequencies for each number of diameters requested.
“CENTRE”:	calculate the natural modes centered around a frequency requested by the LIST_FREQ keyword.
“BANDE”:	calculate the natural modes between two frequencies given by the user by the LIST_FREQ keyword. The natural frequencies are separated by dichotomy and then the natural modes calculated by inverse iterations centered on the frequencies resulting from the separation step.

3.5.3. Operands FREQ/NMAX_FREQ

List of frequencies whose use depends on the option chosen:

We expect 2 values

that define the band.

We expect 1 value which is the central frequency of the interval.

The smallest natural frequencies of the structure are calculated. By default, we calculate the first 10. The keyword FREQ then has no meaning in this case, it does not have to be filled in.

Number of frequencies to be calculated for each number of node diameters requested. If this key word does not appear, as many frequencies are calculated, for each node diameter, as there are natural modes used in the modal base (keyword NB_MODE).

3.5.4. Operands PREC_SEPARE/PREC_AJUSTE/NMAX_ITER

Frequency separation accuracy for option “BANDE”.

Precision used for calculating the modes (all OPTIONS).

Maximum number of reverse iterations (all OPTIONS).

3.6. Keyword VERI_CYCL

♦ VERI_CYCL

Key word for verifying the consistency of data interfaces in terms of cyclical repeatability.

Figure 3.6-a

3.6.1. Operands PRECISION/DIST_REFE

◊ PRECISION = prec

◊ DIST_REFE = dist_ref

The consistency test between 2 contiguous sectors will be determined by the prec*dist_ref product. If DIST_REFE is not entered, it will be automatically calculated in proportion to prec and to a maximum coordinate value for a sector.

3.7. Operand INFO

◊ INFO =

Print Level

1	no printing,
2	writing the frequencies and generalized parameters obtained and the relative participations of the various modes of the base.