| About this Abstract |
| Meeting |
2024 ASC Technical Conference, US-Japan Joint Symposium, D30 Meeting
|
| Symposium
|
2024 ASC Technical Conference, US-Japan Joint Symposium, D30 Meeting
|
| Presentation Title |
Understanding Strain Rates and Defects in Composite Energy Absorbers |
| Author(s) |
Akhil Bhasin, Suresh Keshavanarayana, Tanat Maichan, Luis Gomez, Gerardo Olivares |
| On-Site Speaker (Planned) |
Akhil Bhasin |
| Abstract Scope |
This research aims to evaluate the effects of defects, manufacturing, and in-service damage, on the composite energy absorbers designed to improve the crashworthiness behavior in aircraft structures. Composite energy absorbers undergo multiple failure modes such as fiber fracture, matrix cracking, fiber-matrix debonding, and delamination under compression to dissipate energy. The presence of defects could undermine their load-carrying capabilities by changing the desirable failure modes. Also, during emergency landing conditions the lower lobe of the fuselage would experience elevated strain rates. Thus, it is important to understand the effects of defects on the energy absorbers at varying strain rates.
Experiments were conducted on two energy absorber geometries: corrugated beam, and c-channel stanchions at 0.01 in/s, 1 in/s, and 100 in/s. Manufacturing defects investigated include fiber wrinkling, and delamination introduced during fabrication. In-service impact damage varying from barely visible impact damage (BVID) to VID, was introduced in the pristine energy absorbers post-fabrication. Results from experiments conducted at 1 in/s were presented at earlier ASC technical conferences. This paper will summarize the test results at other stroke rates, and provide a relationship between the strain rates and defects. The test results will include damage evolution, specific energy absorbed, and strains obtained from high-speed three-dimensional Digital Image Correlation (DIC). The FAA funded this research through the JAMS Center of Excellence. |
| Proceedings Inclusion? |
Definite: Post-meeting proceedings |