3. Modeling A

3.1. Characteristics of modeling

3.2. Characteristics of the mesh

The rotor is meshed in 40 finite shaft elements of type POU_D_T regularly distributed and includes 2 discrete elements of type DIS_TRpour: the modeling of the bearings.

Number of knots: 41

Number and type of elements: 40 SEG2

2 POI1

3.3. Tested sizes and results

The relative tolerance criteria are 1% for “SOURCE_EXTERNE” results and 5th -3% for “NON_REGRESSION” results.

The values of the first 6 natural frequencies of the rotor are as follows.

Freq Number	Rotor ASTER	Calculation CADYRO
	\(F\) ( \(\mathit{Hz}\) )	\(F\) ( \(\mathit{Hz}\) )
1	1.00860E+02	1.0090E+02
2	1.00860E+02	1.0090E+02
3	3.92529E+02	3.9305E+02
4	3.92529E+02	3.9305E+02
5	8.50239E+02	8.5242E+02
6	8.50239E+02	8.5242E+02

Table 3.3-1 : Rotor natural frequencies

The values of the first 10 natural frequencies of the massif are as follows.

Freq Number	Rotor ASTER	Calculation CADYRO
	\(F\) ( \(\mathit{Hz}\) )	\(F\) ( \(\mathit{Hz}\) )
1	2.19224E+02	2.21045E+02
2	2.56714E+02	2.59147E+02
3	3.44965E+02	3.47706E+02
4	4.17655E+02	4.20215E+02
5	4.88441E+02	4.92291E+02
6	5.17576E+02	5.21767E+02
7	6.19092E+02	6.24727E+02
8	6.41466E+02	6.45547E+02
9	7.32139E+02	7.36375E+02
10	7.76297E+02	7.78041E+02

Table 3.3-2 : Natural frequencies of the mass

The values of the first 7 frequencies when stopped, for the two calculation methods (direct and substructured), are shown in the table below.

Freq Number	Rotor ASTER direct calculation	Calculus ASTER substructured calculation	Calculation CADYRO
	\(F\) ( \(\mathit{Hz}\) )	\(F\) ( \(\mathit{Hz}\) )	\(F\) ( \(\mathit{Hz}\) )
1	1.00675E+02	1.00675E+02	1.00717E+02
2	1.00827E+02	1.00827E+02	1.00866E+02
3	2.19250E+02	2.19933E+02	2.21064E+02
4	2.56711E+02	2.56822E+02	2.59143E+02
5	3.40422E+02	3.48884E+02	3.42981E+02
6	3.91994E+02	3.92003E+02	3.92524E+02
7	3.96857E+02	3.98334E+02	3.97556E+02

Table 3.3-3 : Natural frequencies obtained by direct and substructured calculations