Fatigue Crack Growth Analysis of the Light Rail Vehicle Braking Disc Under Different Braking Conditions Including Emergency Braking
| dc.contributor.advisor | Celestin, Nkundineza (PhD) | |
| dc.contributor.advisor | Demis, Alemu (PhD) Co-Advisor | |
| dc.contributor.author | Daniel, Liyew | |
| dc.date.accessioned | 2020-03-08T10:56:45Z | |
| dc.date.accessioned | 2023-11-04T15:17:07Z | |
| dc.date.available | 2020-03-08T10:56:45Z | |
| dc.date.available | 2023-11-04T15:17:07Z | |
| dc.date.issued | 2019-11 | |
| dc.description.abstract | Railway brake discs are the safety-critical components usually designed for up to ten years of operation. To guarantee the safety, fracture mechanics method is usually applied to perform the prediction of fatigue crack growth. The main purpose of this study is to analyze the stresses and fatigue crack propagation of disc brake under different speeds and load of AA-LRT train services. Mechanical and thermo-mechanical fatigue crack can often be found on the friction surface of brake discs used in railway vehicles after a period of usage due to exposure on heavy thermal and mechanical stress during braking and radial crack patterns that mostly occur. A brake disc crack exhibits different initiation and propagation behaviors with respect to different braking conditions. In this paper, the effect of braking energy on brake disc fatigue crack evolution is investigated by using a novel Extended Finite Element Method (XFEM) implemented in ABAQUS software for a train operating at acceptable and over speed at room temperature (25 o C) and at higher temperature (500 o C). Simulations at 4, 8, 12, 16 and 20mm crack length reveal that crack propagation the maximum effective stress intensity factor increase from as the crack length increased and accordingly the crack propagation rate increases at the crack size become large. On the other hand, the effect of temperature and speed were observed from the results to contribute to the increase of crack propagation for larger crack size. In all cases, over speed and high temperature, as the braking is applied repeatedly, lead to increased propagation rate of the crack on the friction surface of the disc. | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/123456789/21024 | |
| dc.language.iso | en_US | en_US |
| dc.publisher | Addis Ababa University | en_US |
| dc.subject | Brake disc | en_US |
| dc.subject | Mechanical stress | en_US |
| dc.subject | Thermal stress | en_US |
| dc.subject | Crack propagation | en_US |
| dc.title | Fatigue Crack Growth Analysis of the Light Rail Vehicle Braking Disc Under Different Braking Conditions Including Emergency Braking | en_US |
| dc.type | Thesis | en_US |