5. C modeling#

5.1. Characteristics of modeling#

3D modeling is used.

Two calculations are performed that differ only in the integration algorithm: “NEWTON” and “RUNGE_KUTTA”.

In this case, the coefficient \({K}_{D}\) is chosen only depending on the temperature.

T (°C)

900

1000

1025

\({K}_{D}\)

15

15

15

Table 5.1-1 : K_D of C modeling

The discretization in time is quite fine:

(JUSQU_A = 2, NOMBRE = 10),

(JUSQU_A = 2., NOMBRE = 10),

(JUSQU_A = 20., NOMBRE = 10),

(JUSQU_A = 200., NOMBRE = 10),

(JUSQU_A = 2000., NOMBRE = 10),

(JUSQU_A = 20000., NOMBRE = 10),

(JUSQU_A = 200,000., NOMBRE = 10),

(JUSQU_A = 1000000., NOMBRE = 30),

(JUSQU_A = 1600000., NOMBRE = 30),

(JUSQU_A = 1700000., NOMBRE = 40),

(JUSQU_A = 1800000., NOMBRE = 40),

(JUSQU_A = 1900000., NOMBRE = 40),

(JUSQU_A = 2000000., NOMBRE = 40),

(JUSQU_A = 2100000., NOMBRE = 40),

(JUSQU_A = 2200000., NOMBRE = 40),

(JUSQU_A = 2300000., NOMBRE = 40),

(JUSQU_A = 2400000., NOMBRE = 40),

(JUSQU_A = 2500000., NOMBRE = 40),

5.2. Characteristics of the mesh#

It is chosen to represent the cylindrical test piece by a block in order to be able to perform a calculation on a single element. The modeling has 3 planes of symmetry.

Number of knots: 8

Number of stitches: 1 (HEXA8)

_images/100002010000027E000002A9D2D338CDC42533CB.png

Figure 5.2-1: C modeling mesh

5.3. Tested sizes and results#

5.3.1. Case RUNGE_KUTTA + Matrix ELASTIQUE#

Evolution of the constraint, \({\sigma }_{0}\), as a function of time. This value is tested at various times:

Instant

Reference Type

Reference

Tolerance (%)

20

“ANALYTIQUE”

253.02000000000001

0.5

2000

“ANALYTIQUE”

164.36000000000001

0.5

200000

“ANALYTIQUE”

102.16

0.5

1000000

“ANALYTIQUE”

79.920000000000002

0.5

1600000

“ANALYTIQUE”

70.900000000000006

1.0

Table 5.3.1-1 : C modeling results

Evolution of the damage variable, \(D\) as a function of time. This value is tested at various times depending on the modeling:

Instant

Reference Type

Reference

Tolerance (%)

20

“ANALYTIQUE”

2.32E-4

0.5

2000

“ANALYTIQUE”

2.7399E-3

0.5

200000

“ANALYTIQUE”

0.027560999999999999

0.5

1000000

“ANALYTIQUE”

0.066266500000000006

1.0

1600000

“ANALYTIQUE”

0.090278800000000006

1.0

Table 5.3.1-2 : C modeling results

Evolution of the viscoplastic isotropic work hardening variable, \(r\), as a function of time. This value is tested at various times:

Instant

Reference Type

Reference

Tolerance (%)

20

“ANALYTIQUE”

1.645999999999999999E-3

0.5

2000

“ANALYTIQUE”

2.2339E-3

0.5

200000

“ANALYTIQUE”

2.6282800000000002E-3

0.5

1000000

“ANALYTIQUE”

2.7522900000000001E-3

0.5

1600000

“ANALYTIQUE”

2.799299999999999998E-3

0.5

Table 5.3.1-3 : C modeling results

Evolution of the isotropic visco-plastic work hardening variable, \(p\), as a function of time. This value is tested at various times:

Instant

Reference Type

Reference

Tolerance (%)

20

“ANALYTIQUE”

1.6461E-3

0.5

2000

“ANALYTIQUE”

2.234499999999999999E-3

0.5

200000

“ANALYTIQUE”

2.6329000000000001E-3

0.5

1000000

“ANALYTIQUE”

2.762699E-3

0.5

1600000

“ANALYTIQUE”

2.8137000000000001E-3

0.5

Table 5.3.1-4 : C modeling results

5.3.2. Case NEWTON + Matrix TANGENTE#

The quantities tested are the same as in the previous case. On the other hand, the tolerance is 4% (for all values tested).