PSI - Issue 42

Rogério Lopes et al. / Procedia Structural Integrity 42 (2022) 1159–1168 Rogério F. F. Lopes et al./ Structural Integrity Procedia 00 (2019) 000 – 000

1164

6

latch trigger rod. It consists in a hydraulic cylinder operating a rod that mechanically triggers a latch locking a hook connected to the swinging mass, as shown in the Fig. 4.b). Once the hydraulic cylinder is pressurized (at the rod side chamber), the rod retracts quickly and the pendulum is released for its downward impact travel.

a) b) Fig. 4. a) Experimental overview of the ECE 29 test bench: (1) coach section, (2) impactor structure, (3) fixing structure and (4) overhead crane and b) pendular system in drop position with the quick release system The numerical simulation step is the study's core, requiring extensive computer resources due to the high degree of complexity in its modeling for best accuracy. The modeling method is separated into phases, beginning with mesh assignment in the various integrating components and progressing through connection and connector element assignment. Creating intermediate surfaces on components such as panels, glasses, and chassis elements involves the use of specialized processes. In Abaqus, the mesh was defined and the intermediate surface was specified. The model was imported and finished in PamCrash, which was thoroughly tested to perform the ECE R-29 coach frontal crash test. Shell elements are the core of the finite elements analysis (FEA). However, solid elements were used to model specific components such as the steering wheel, seat, and tanks. Bar elements, on other hand, make up a minor percentage of the linear components in the chosen formulation. As a complementary virtual equipment, an impactor with the geometry complying the regulation was modelled and brought to impact the coach section in the pre-defined position, resulting in a movement similar to that observed experimentally. Fig. 5 depicts the FE model. Table 1 contains a summary of the components used in this FEA. Regarding the formulations: Belytschko-Tsay uniform reduced integration for structural components; Timoshenko Formulation to 1D elements; Uniform reduced Integration to 3D elements; and Uniform Reduced Integration with Mean strain is used to model 3D elements of the seat made of foam.

Table 1. Summary of the components and the respecting number

Beam Elements

Triangular Elements

Quadrangular Elements

Solid Elements

Boundary Conditions

Component

Nodes

Parts

Contacts

No.

593481

189

2473

498871

128944

525

3

2