アコースティックエミッション法を用いた行者匹二枚貝の配管付着状態検出法の開発

抄録

Clogging of water intake pipes by sessile bivalves is a serious problem hindering the safe operation of industrial and power plants. We developed a system to monitor such clogging by means of an acoustic emission (AE) technique. A sheet-type optical fiber sensor developed in our laboratory was used to monitor AE signals produced by single individuals or colonies of mussel Mytilus galloprovincialis attached by their byssus inside a PMMA pipe. No relation was found between mussel size and peak frequency of AE signal; However, the mussels each had a characteristics frequency, and the scattering of AE signals frequencies corresponded to the number of mussels in a colony. In addition, the AE signal generation rate increased with increasing numbers of mussels in the pipe, but continuous monitoring showed that the signal genera- tion rate also increased when mussels were removed. Continuous monitoring is thus needed if pipe clogging is to be monitored effectively by this AE technique.