PSI - Issue 47

Andre Hartawan Mettanadi et al. / Procedia Structural Integrity 47 (2023) 168–175 Mettanadi et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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4. Result and discussion of Cyl-1 characteristic 4.1. Benchmarking results

After conducting a study of Cyl-1, the following results showed that the peak crushing force (PCF) was 92.38 kN. In addition, the Mean Crushing Force (MCF) marked in Figure 6b which is equal to the ratio of energy absorbed to the cut-off displacement. The average experimental and simulated crushing forces from benchmarking were compared with the numerical results obtained, namely 77.99 kN, 79.12 kN, and 79.09 kN, respectively. The resulting results are close to the benchmark's simulation results and are slightly larger than the experimental results with an error ratio of 5%. Based on Figure 7a, it can be seen that the displacement that occurs using a mesh size of 1 mm is quite even on the surface of BBT-1 and Cyl-1.

t =0 ms

120000

t =1.95ms

t =3.9ms

t =5.8ms

90000

t =8ms

60000

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BBT-1

Force ( N )

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Simulation ( Cyl-1 ) MCF Numerical Benchmark Simulation Benchmark Experiment MCF Experiment

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Cyl-1

(b)

Displacement (mm)

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(c) (d) Figure 7. Calculation results and comparisons: (a) displacement contours of BBT-1 compared to Cyl-1; (b) numerical result compared with benchmark’s result; (c) stress contour at time step 8 ms; and (d) strain contour at time step 8 ms. In data comparison based on the summarized lines in a chart, the graph between the reference and the study already has a similar trend line (can be seen in Figure 7b). The similarity is seen in the elastic part where the two curves coincide. In addition, the similarity can be seen in the post-buckling, where the two curves also coincide. However, in existing studies, there is a necking when it crosses the yield limit. It can also be observed that in the results of studies carried out the displacement began to be unstable after passing 110 mm, different from the