PSI - Issue 33

5

Muhammad Sabiqulkhair Akbar et al. / Procedia Structural Integrity 33 (2021) 67–74 Akbar et al. / Structural Integrity r ce ia 00 (2019) 000–000

71

0 0,2 0,4 0,6 0,8 1 1,2 1,4 1,6 1,8

Deformation Ratio

5

6

7

8

9

10

11

ELT Ratio

Fig. 3. Convergence study considering displacement ratio of the FE simulation.

3.2. Strain ratio The strain ratio (see Table 5) is calculated by dividing the strain analysis value by the strain benchmark value. All of the simulation results can be seen in Table 5. The first variation midship simulation has a strain ratio of 1.423. The strain ratio in the second variation is 1.177. The strain ratio in the third variation is 1.019. Simulation for the fourth variation has a strain ratio of 0.933. The strain ratio for the fifth variation is 0.863. The strain ratio for the sixth variation is 0.778. The strain ratio in the last variation is 0.647. Several strain contours based on FE simulation are presented in Fig. 4. The simulation outcome of the strain ratio represents graphically in Fig. 5. When the ELT values are 7, 8, and 9, as shown in the graph, the value begins to approach convergence. The closest stress ratio results when the ELT value is 7 with a ratio of 1.035, the nodes is 74016, the elements are 38009, and the error compared with the benchmark study is 3.5 percent.

Table 5. Strain ratio of the midship model. ELT Ratio Nodes

ε (x 10 -4 )

Benchmark ε (x 10 -4 )

ε Ratio

Elements

5 6 7 8 9

138521 93057 74016 56612 46044 36946 28757

70667 47686 38009 29184 23890 19191 15065

7.722 6.998 6.296 5.599 6.355 5.579 5.312

6.082 6.082 6.082 6.082 6.082 6.082 6.082

1.27 1.15

1.035

0.92

1.044 0.917

10 11

0.87

(a)

(b)