Unusual Attenuation Recovery Process After Fiber Optic Cable Irradiation

27th Joint Seminar Development of Materials Science in Research and Education

材料科学;教育

Konená, Z.^1 ; Plaek, V.^2 ; Havránek, P.^2

Czech Technical University in Prague, Department of Electrotechnology, Technická 2, Praha, Czech Republic^1

ÚJV e, A. S., Hlavní 130, e, Husinec, Czech Republic^2

关键词: Healing process;    Instrumentation and control system;    Limitation factors;    Radiation environments;    Radiation Exposure;    Recovery process;    Signal attenuation;    Signal loss;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/266/1/012005/pdf
DOI  :  10.1088/1757-899X/266/1/012005

来源: IOP

【 摘 要 】

At present, the number of optical cables in nuclear power plants has been increasing. Fiber optic cables are commonly used at nuclear power plants in instrumentation and control systems but they are usually used in environments without radiation. Nevertheless, currently, the number of applications in NPP containment with radiation is increasing. One of the most prevalent effects of radiation exposure is an increase of signal attenuation (signal loss). This is the result of fiber darkening due to radiation exposure and it is the main limitation factor in application of fiber optics in radiation environment. However, after the irradiation, the fiber optics go through a "recovery process" during which the optical properties improve again; i.e. attenuation decreases. However, we have found cable, where the expected healing process after few days changed its trend and the attenuation increased again to a value well above the attenuation just after the irradiation. This paper describes experiments that were carried out to explain this unusual recovery behaviour.