マイクロ波入射部最適化によるマイクロ波探傷技術の高度化
Enhancement of microwave nondestructive testing method for the inspection of pipes by optimizing the microwave probe profile
佐々木 幸太*; 遊佐 訓孝*; 若井 隆純 ; 橋爪 秀利*
Sasaki, Kota*; Yusa, Noritaka*; Wakai, Takashi; Hashizume, Hidetoshi*
本論文は、配管の非破壊検査に用いる新しいマイクロ波探触子の開発について述べる。マイクロ波探触子の形状を最適化するために、三次元有限要素解析を行った結果、楕円形状の探触子が小さい反射を可能とし、また従来のものに比べ良い結果をもたらした。内径39mm、長さ2mの直管を用いた検証実験を行い、新しいマイクロ波探触子は模擬的な矩形状減肉の信号をより鮮明に与えることがわかった。
This study reports the development of a new microwave probe for the nondestructive testing of a pipe. Three-dimensional finite element simulations are carried out to optimize the profile of a microwave probe, whose results show that a probe with elliptic profile enables smaller reflection at the probes as well as much better single-mode propagation inside the pipe than conventional ones. Experimental validations are carried out using a straight brass pipe with an inner diameter of 39 mm and a total length of 2 m. The results of the experiments clearly demonstrate that the new microwave probe provides clearer signals due to simulated rectangular wall thinning.