Factors in fiber manufacturing procedures affect fiber¡¦s production, and the fiber quality will be affected accordingly. The residual stresses, in particular, have a significant influence on fiber quality, due to the mechanical strength and the refraction rate that has been changed. Mechanically, residual stresses may cause ruptures in the preform, reducing the intrinsic strength of the fiber and its durability; optically, it may also cause anisotropic distortions of the refractive index profiles.
In the process of cooling under high temperature, fiber core and cladding will be compressed owing to the material difference and the residual stress will be in the fiber. Thermal conductance and thermal expansion coefficient contribute to the cracks on the interface and thus affect the refraction rate. Experiments have shown that quartz and Cr4+¡GYAG will rupture on the interface as a result of the huge thermal expansion coefficient. According to researches, stress in different directions will bring about fiber cracks or changes of the refraction rate.
This paper mainly investigates the influence of material properties on the temperature field and thermal stress distribution in the cooling process of fiber and preform manufacturing by numerical simulations. The results show the preform temperature profile and the stress distribution in different directions. Also, through the stress distribution, the stress is known to be centered on the interface between core and cladding.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0818109-180903 |
| Date | 18 August 2009 |
| Creators | Lai, Sheng-shin |
| Contributors | Ming-Huei Yu, Jerry-Min Chen, Wen-Mei Yang, Cheng-Hsiung Kuo |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0818109-180903 |
| Rights | not_available, Copyright information available at source archive |
Page generated in 0.0024 seconds