The distance between the acoustic-emission source and the receiving transducer, and the background noise level are primary factors in selecting a particular frequency band.
声发射源与接收讯号传感器间的距离以及环境噪声的电平是选择频带的主要依据。
2
The transducer emits ultrasonic waves into the fluid that are not parallel to the primary flow of fluid through the tank.
该换能器发射不平行于穿过该容器的主要流体流的超声波进入流体。
3
A health monitoring and fault detect primary scheme is given including optimization on monitoring position and quantity, transducer type selection, fault information abstraction and detect methods.