PSI - Issue 52

Wu Zonghui et al. / Procedia Structural Integrity 52 (2024) 203–213 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Table 2. Design dimensions of the marine lubricating oil cooler(mm). L H t 3310 930 15

Table 3. Random variables in material properties. Variable Unit Probabilistic distribution

Mean value, μ

COV Standard deviation, σ

Mpa Gpa

Normal Normal

396 195

0.05 0.05

19.8 9.75

σ s

E p

Fig. 9. Plus-minus triangular wave.

Table 4. Parameters in plus-minus triangular wave. A 1 A 2

t 1

t 2

t 3

t 4

Vertical impact load Transverse impact load

-0.93 A 0 -0.28 A 0

5.3(ms) 5.4(ms)

13.2(ms) 13.5(ms)

21.8(ms) 30.4(ms)

27.5(ms) 41.7(ms)

A 0

0.59 A 0

The failure criterion, in this case, is given as: ,max s m g   = − (8) where σ s is the dynamic yield strength and σ m, max is the maximum of Mises stress in the whole model computed by ABAQUS. Fig.10 is finite element calculation result ( t =15mm, σ s =414.06Mpa, E p =227.76Gpa and A 0 =56.67 g ) and the point M is the max Mises stress location.

Fig. 10. Finite element calculation result.

Above all, four random variables ( t , σ s , E p and A 0 ) are referred. The mean reliability index computed by the ANNs with 900 samples is considered as the approximation of the exact solution as ANNs perform well with enough samples. Table 5 indicates the result of ANNs with large-size samples and the exact value β =4.422, and performances of ANNs